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Fatty Acids in Blue-Green Algae: Possible Relation to Phylogenetic Position
Abstract
Analyses of the lipids in five species of blue-green algae show that the fatty acids are largely the C(16) and C(18) acids. The only alga that could be grown heterotrophically, Chlorogloea, formed the triply unsaturated C(18) acid in the light but only the doubly unsaturated C(18) acid in the dark. Examination of these results and the results of others suggest that, except for one species, the more highly unsaturated acids are found in the morphologically more complex algae. The fatty acid compositions of blue-green algae are different from the fatty acid composition of the other prokaryotic organisms, the bacteria. It is speculated that the diversity of the patterns of fatty acid composition among the blue-green algae could be of phylogenetic significance.
... Current conclusions on modes of FA desaturation in cyanobacteria are solely based on biochemical analysis of FAs and lipid classes [8][9][10][11][12][13][14]. Modern advances in sequencing techniques allowed determination of the whole genomes of various cyanobacterial strains. ...
... Table 1. Fatty-acid composition of the total lipids from various cyanobacterial strains (adapted from Murata et al. 1992 [13]). 18:4 Δ 9 Δ 9 Δ 9,12 Δ 9 Δ 9,12 Δ 9,12,15 Δ 6,9,12 Δ 6, 9,12,15 Group 1 Mastigocladus laminosus ...
... According to previously proposed classification, the cyanobacterial strains that synthesize trienoic α-linolenic acid, 18:3∆ 9,12,15 were assigned to Group 2. These organisms have three distinct FA desaturase activities: Δ9-, ∆12-and ∆15-desaturases. Organisms of a former Group 3 also have three distinct desaturases, but, instead of ∆15, they introduce a third double bond at position ∆ 6 and produce trienoic γ-linolenic acid, 18:3∆ 6,9,12 , as a final product of desaturation. ...
Fatty acid composition of individual species of cyanobacteria is conserved and it may be used as a phylogenetic marker. The previously proposed classification system was based solely on biochemical data. Today, new genomic data are available, which support a need to update a previously postulated FA-based classification of cyanobacteria. These changes are necessary in order to adjust and synchronize biochemical, physiological and genomic data, which may help to establish an adequate comprehensive taxonomic system for cyanobacteria in the future. Here, we propose an update to the classification system of cyanobacteria based on their fatty acid composition.
http://www.mdpi.com/2075-1729/5/1/554/htm
... One possible source of aromatic** kerogen in Early Precambrian sediments is sporopollenin (Brooks and Shaw, 1968 found in algal and fungal spore exines. Another is the polymerization of unsaturated fatty acids (Abelson, 1967) of blue-green algae (Parker and Leo, 1965;Parker et al., 1967;Holton et al., 1968;Margulis, 1969;Kenyon and Stanier, 1970;Schneider et al., 1970) during diagenesis of *The microbiota of the Swaziland System possibly included both heterotrophs and bacterial (but not necessarily algal) autotrophs (Kvenvolden, 1972). ** Brooks and Shaw (1971) argued that sporopollenin derived largely from a carotenoid ester (as opposed to a free carotenoid) will be of an aliphatic type. ...
... Polyunsaturated fatty acids, like sterols, are also more characteristic of eukaryotes than prokaryotes (Margulis, 1969(Margulis, , 1970b. The biosynthesis of sterols involves molecular oxygen (Bloch, 1965); and polyunsaturated fatty acids have been thought to participate in oxygen production during "green plant" photosynthesis (Erwin and Bloch, 1963), although their exact function is not yet understood (Holton et al., 1968). The appearance of the eukaryotic cell "with its potentialities for mitosis, meiosis, and genetic exchange via sexuality" (Schopf, 1969, p.162) also presupposes an established ozone layer in the atmosphere to screen out lethal ultra-violet radiation and permit the gradual expansion of the biosphere into less protected, more freely planktonic habitats to commence (Cloud, 1968a). ...
... Small amounts of polyunsaturated fatty acids (Parker et al., 1967;Holton et al., 1968;Kenyon and Stanier, 1970) and sterols (De Souza and Nes, 1968;Reitz and Hamilton, 1968) have now been found in certain species of extant blue--green algae. Nevertheless, the accumulation of detectable quantities of these compounds in the geological record would seem to be likely only after the evolution, diversification, and proliferation of aerobic eukaryotic organisms. ...
Cherts, shales, and carbonates containing small amounts of organic matter occur throughout the Precambrian sedimentary record. The oldest known organic-rich sediments have been dated at > 3,000 million years. Knowledge of the composition, origin, and fate of the organic content of these rocks relates to many facets of Precambrian earth history. Apart from its primary paleobiological significance, organic geochemical research is also concerned with problems in atmospheric and hydrospheric evolution, sedimentation, diagenesis, metamorphism, and ore genesis.
... Lecithin, phosphatidyl ethanolamine, and phosphatidyl inositol have not been found in these algae (567). Tabulations of the abundance of different fatty acids, principally C14, C1s, and C18, in a variety of blue-green algae may be found in a number of publications (399,452,567,620). The absence of a-linolenic acid (18:3 [3,6,9]) from A. nidulans and certain other bluegreen algae (398,452,453,567,620,729) shows that, although a-linolenic acid is common to eukaryotic photosynthetic plants, it cannot be a requirement for the photosynthetic production of oxygen. ...
... However, a-linolenic and (or) -y-linolenic acid (18:3 [6,9,12]) is present in other blue-green algae (452,453,512,567,568,620,729). The absence of a-linolenic acid is not restricted to unicellular blue-green algae: Hapalosiphon laminosus, which has a branched, filamentous habit, also lacks fatty acids with three double bonds (399,568). Branched-chain fatty acids are almost completely absent from blue-green algae (620). Capric acid (10: 0), elsewhere rare, can comprise as much as 50% of the fatty acids of Trichodesmium (620). ...
... In this study, PA was obtained from a fish oil-producing company, which may be perceived as expensive. However, some species of blue-green algae contain a significant amount of PA (39 to 45.8 g/100 g total FA) and can serve as a cheaper and sustainable source (Holton et al., 1968;Lang et al., 2011). It is also worth exploring if maternal supplementation of PA during late gestation could alter the FA metabolism of sows and thus influence the PA composition of the sow's colostrum and milk, leading to improved survival and growth of piglets. ...
Piglet survival is a major challenge in the first few days postpartum and interventions during this period may improve survival and growth. This study investigated the effects of palmitoleic acid (C16:1n-7; PA) supplementation on growth performance, body temperature, fatty acid (FA), and energy metabolism in milk-replacer-fed piglets. Forty-eight piglets were stratified by body weight and randomly assigned to one of four dietary treatments (0%, 1%, 2%, and 3% PA supplementation as a percent of milk replacer) and given the diet through an orogastric tube. They were fed dietary treatments every 2 h for 4 d in the first week postpartum and all were sacrificed at the end of the experiment. The piglets were weighed daily, and half in each dietary treatment group, the same piglets each day, were exposed daily to a lower temperature for 2 h. Plasma samples were collected immediately before sacrifice for analyses of FA and other plasma metabolites. The weight of organs and empty body weight were determined after sacrifice. Liver and semimembranosus muscle tissue samples were collected and analyzed for FA content. Contents of C16:1n-7 and C18:1n-7 in both plasma and liver (P < 0.001), and C16:1n-7 in semimembranosus muscle (P < 0.001) increased linearly as PA supplementation increased. Most plasma FA levels (except C16:1n-7, C16:1n-9, and C22:5n-3) were lower in piglets exposed to lower temperature than those that were not. Plasma glucose, triglycerides, and lactate dehydrogenase levels increased linearly with PA supplementation (P < 0.001). Piglets’ average daily gain, liver glycogen pool, liver weight, and gallbladder weight increased linearly (P < 0.05, P < 0.01, P < 0.05, and P < 0.001, respectively), but lung weight, liver nitrogen content, and body temperature drop decreased linearly (P < 0.01, P < 0.001, and P < 0.05, respectively) with PA supplementation. Piglets exposed to low temperature had greater liver nitrogen (P < 0.05) and lactate dehydrogenase (P < 0.001) contents but had lower liver weight (P < 0.01) and plasma lactate concentration (P < 0.05) than those that were not. In conclusion, this study demonstrated the importance of PA on the growth performance of the piglets by increasing their average daily gain and decreasing a drop in body temperature upon cold exposure, most likely due to a modified energy metabolism.
... This is in contrast to other cyanobacteria that are typically dominant in the presence of hexadecanoic and octadecanoic acids (C 16 and C 18 ). 13,14 In a 1967 study describing fatty acids in blue-green algae, Parker et al. sampled surface blooms of T. erythraeum near Port Aransas in the Gulf of Mexico. They found that one bloom contained 50% C 10 fatty acid and noted that this pattern was striking because it was a relatively rare fatty acid. ...
The bloom-forming cyanobacteria Trichodesmium contribute up to 30% to the total fixed nitrogen in the global oceans and thereby drive substantial productivity. On an expedition in the Gulf of Mexico, we observed and sampled surface slicks, some of which included dense blooms of Trichodesmium erythraeum. These bloom samples contained abundant and atypical free fatty acids, identified here as 2-methyldecanoic acid and 2-methyldodecanoic acid. The high abundance and unusual branching pattern of these compounds suggest that they may play a specific role in this globally important organism.
... Cellular Fatty-Acid Composition Nearly all bacteria, including the photosynthetic purple and green bacteria, contain only saturated and monounsaturated fatty acids (38) Eucaryotes also contain polyunsaturated fatty acids. With respect to cellular fatty-acid composition, the blue-green algae are heterogeneous (34,49,50,54). The most extensive comparative analysis so far published (39) showed that the majority of filamentous blue-green algae (15 of 17 strains examined) contain large amounts of polyunsaturated fatty acids, whereas the majority presence is revealed by a peak or shoulder in the in vivo spectrum at approximately 570 nm. ...
... Recently, molecular methods using 16S rRNA have been used to characterize cyanobacterial species and bacterial methods such as cellular fatty acid composition have also been proposed for cyanobacteria (Descy et al. 2000, Li and Watanabe 2004, Guedes et al. 2011. Holton et al. (1968) and Kenyon and Stanier (1970) suggested that the morphologies of cyanobacteria correlate with the concentration of cellular unsaturated fatty acid levels. Kom arek has pioneered modern cyanobacterial taxonomy by combining all available methods. ...
... Among cyanobacteria, hexadecadienoic FAs have been found in some strains of Nostoc (Holton, Blecker and Stevens 1968;Sallal, Nimer and Radwan 1990), Anabaena (Li and Watanabe 2001), Spirulina subsalsa and Planktothrix agardhii NIES-204 (Li et al. 1998), Tolypothrix sp. (Maslova et al. 2004), Oscillatoria williamsii (Parker et al. 1967), Chamaesiphon minutus PCC 6605, Cyanothece sp. ...
Cyanobacteria are prokaryotic photosynthetic organisms widely used in biotechnology, photosynthesis and abiotic stress research. There are several cyanobacterial strains modified to produce biofuels, but the influence of alcohols on cyanobacterial cell physiology is poorly understood. Here, we conducted a systematic study of the effects of nine primary aliphatic alcohols and an aromatic benzyl alcohol on both membrane physical state and the expression of genes for fatty acid desaturases (FADs) in a model cyanobacterium Synechocystis sp. strain PCC 6803. Hexan‐1‐ol was found to have the most membrane fluidizing action among all alcohols studied, with its efficiency correlating with both duration of treatment and alcohol concentration. A prolonged exposure to alcohol results in a continuous loss of unsaturated fatty acids followed by cell death, an undesired challenge that should be considered in cyanobacterial biotechnology. We suggest that membrane fluidization is the key component in alcohol stress causing inactivation of FADs and resulting in a lethal depletion of unsaturated fatty acids. Due to the most pronounced effects of alcohol‐ and heat‐induced membrane fluidization on desB encoding a terminal ω3‐FAD, we propose to call desB a “viscosity gene” in analogy to heat‐induced “fluidity gene” hspA.
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... In unicellular, non-heterocystous and heterocystous cyanobacterial species, no ARA was detected but different C 18 FAs (C 18:1 , C 18:2 , C 18:3 (a-and c-types) as well C 18:4 FAs) [28]. According to Pushparaj et al. [29], ARA was only found in cyanobacterium, Phormidium pseudopristleyi strains 79S11 and 64S01 recording 24% and 32% of their total FA contents, respectively. ...
Some of the essential polyunsaturated fatty acids (PUFAs) as ARA (arachidonic acid, n-6), EPA (eicosapentaenoic acid, n-3) and DHA (Docosahexaenoic acid, n-3) cannot be synthesized by mammals and it must be provided as food supplement. ARA and DHA are the major PUFAs that constitute the brain membrane phospholipid. n-3 PUFAs are contained in fish oil and animal sources, while the n-6 PUFAs are mostly provided by vegetable oils. Inappropriate fatty acids consumption from the n-6 and n-3 families is the major cause of chronic diseases as cancer, cardiovascular diseases and diabetes. The n-6: n-3 ratio (lower than 10) recommended by the WHO can be achieved by consuming certain edible sources rich in n-3 and n-6 in daily food meal. Many researches have been screened for alternative sources of n-3 and n-6 PUFAs of plant origin, microbes, algae, lower and higher plants, which biosynthesize these valuable PUFAs needed for our body health. Biosynthesis of C18 PUFAs, in entire plant kingdom, takes place through certain pathways using elongases (Elo) and desaturases (Des) to synthesize their needs of ARA (C20-PUFAs). This review is an attempt to highlight the importance and function of PUFAs mainly ARA, its occurrence throughout the plant kingdom (and others), its biosynthetic pathways and the enzymes involved. The methods used to enhance ARA productions through environmental factors and metabolic engineering are also presented. It also deals with advising people that healthy life is affected by their dietary intake of both n-3 and n-6 FAs. The review also addresses the scientist to carry on their work to enrich organisms with ARA.
... Cellular Fatty-Acid Composition Nearly all bacteria, including the photosynthetic purple and green bacteria, contain only saturated and monounsaturated fatty acids (38) Eucaryotes also contain polyunsaturated fatty acids. With respect to cellular fatty-acid composition, the blue-green algae are heterogeneous (34,49,50,54). The most extensive comparative analysis so far published (39) showed that the majority of filamentous blue-green algae (15 of 17 strains examined) contain large amounts of polyunsaturated fatty acids, whereas the majority presence is revealed by a peak or shoulder in the in vivo spectrum at approximately 570 nm. ...
... Among cyanobacteria, hexadecadienoic FAs have been found in some strains of Nostoc (Holton, Blecker and Stevens 1968;Sallal, Nimer and Radwan 1990), Anabaena (Li and Watanabe 2001), Spirulina subsalsa and Planktothrix agardhii NIES-204 (Li et al. 1998), Tolypothrix sp. (Maslova et al. 2004), Oscillatoria williamsii (Parker et al. 1967), Chamaesiphon minutus PCC 6605, Cyanothece sp. ...
A cyanobacterial strain from freshwater Lake Shar-Nuur (Mongolia) was isolated and characterized by a polyphasic approach. According to the 16S ribosomal RNA gene sequence, this strain (IPPAS B-1220) belongs to a newly described genus Desertifilum In general, strains of Desertifilum maintain their genetic stability, as seen from analysis of 16S rRNA gene and 16S-23S rRNA internal transcribed spacer sequences from strains collected at distant locations. The newly discovered strain is characterized by an outstanding fatty acid composition (16:1(Δ7) and 16:2(Δ7,10)). Analysis of its draft genomic sequence reveals the presence of six genes for the acyl-lipid desaturases: two Δ9-desaturases, desC1 and desC2; two Δ12-desaturases, desA1 and desA2; one desaturase of unknown specificity, desX; and one gene for the bacillary-type desaturase, desG, which supposedly encodes an ω9-desaturase. A scheme of fatty acid desaturation pathway that describes the biosynthesis of 16:1(Δ7) and 16:2(Δ7,10) fatty acids in Desertifilum is proposed.
... Recently, molecular methods using 16S rRNA have been used to characterize cyanobacterial species and bacterial methods such as cellular fatty acid composition have also been proposed for cyanobacteria (Descy et al. 2000, Li and Watanabe 2004, Guedes et al. 2011. Holton et al. (1968) and Kenyon and Stanier (1970) suggested that the morphologies of cyanobacteria correlate with the concentration of cellular unsaturated fatty acid levels. Kom arek has pioneered modern cyanobacterial taxonomy by combining all available methods. ...
Cyanobacteria occupy many niches within terrestrial, planktonic, and benthic habitats. The diversity of habitats colonized, similarity of morphology, and phenotypic plasticity all contribute to the difficulty of cyanobacterial identification. An unknown marine filamentous cyanobacterium was isolated from an aquatic animal rearing facility having mysid mortality events. The cyanobacterium originated from Corpus Christi Bay, TX. Filaments are rarely solitary, benthic mat forming, unbranched, and narrowing at the ends. Cells are 2.1 x 3.1 µm (width x length). Thylakoids are peripherally arranged on the outer third of the cell; cyanophycin granules and polyphosphate bodies are present. Molecular phylogenetic analysis in addition to morphology (transmission electron microscopy and scanning electron microscopy) and chemical composition all confirm it as a new genus and species we name Toxifilum mysidocida. At least one identified Leptolyngbya appears (based on genetic evidence and TEM) to belong to this new
... Morphological diversity is known to have a strong correlation with biochemical parameters (Holton et al. 1968).These gram-negative prokaryotes exhibit a great morphological diversity along with wide spectra of physiological properties. ...
Two strains of Nostoc commune have been isolated from the soils of two different rice-growing agro-ecosystems, viz. flat and terrace paddy fields of Dima Hasao district of the state of Assam, North-East India. Phenotypic characterization was made for both the strains and their growth, pigments (chlorophyll a, total carotenoid content and phycobiliproteins) and biochemical properties (total carbohydrate and soluble proteins) were studied. Phylogenetic comparison was made utilizing 16S rRNA gene sequences. Both strains presented higher phycocyanin content than other biliprotein pigments. Total carotenoid content (TCC) was higher in the strain isolated from flat paddy field, while the isolate from terrace paddy field was richer in phycobiliproteins. 16S rRNA gene sequences of the isolated N. commune strains were compared with available sequences of other strains of Nostoc and Anabaena from various geographical locations. Gene sequences were clustered according to their geographical origin, which also reflected the disputed taxonomic position of the Nostocacean genera Nostoc and Anabaena.
... The composi tion of specific fatty acids or their ratios have been used as indicators for the identification of bacteria (chemotaxonomic investigations) (Shaw, 1974). Species specificity differences among fatty acid classes, their phylogenic significance have been shown by various reports (Holton et al., 1963;Ackman et al., 1968;Kenyon and Stainer, 1970;Kenyon, 1972;BenAmotz et al., 1985BenAmotz et al., , 1987. Numerous algal species and strains belonging to Chlorophyceae have been repor ted to contain, based on conventional solvent extraction and gravimetric analyses, high levels (25-50% of dry weight) of neutral lipids, sug gesting that this class of microalgae may repre sent a large pool of organisms that could be useful for lipid/oil feedstock production (Hu et al., 2006(Hu et al., , 2008. ...
... La longueur des chaînes d'acides gras, la position des doubles liaisons et des groupes substituants ont été utilisés pour caractériser de nombreux taxons bactériens (Tighe et al, 2000). Holton et al (1968) ont donc proposé l'utilisation des acides gras dans des études phylogénétiques. Selon ce critère, plusieurs études ont ainsi montré que les cyanobactéries pouvaient être séparées selon 4 groupes, en corrélation avec la classification morphologique de l'époque (Kenyon & Stanier, 1970 ;Kenyon et al, 1972). ...
Currently, the systematics of cyanobacteria is based on morphology. However, using
molecular characters, particularly 16S rDNA, has changed the systematics. In many cases, the
morphological and molecular characters were not congruent. Moreover, the phylogenetical
analyses are based on cyanobacterial strains, cultivated and maintained in collection. However,
many species have not been isolated and/or are not cultivable. Actually, the use of morphological,
genetical, physiological and biochemical characters in a polyphasic approach is
necessary to characterize strains and to improve cyanobacterial systematics.
In this context, this work has contributed to implemente data bases with the cyanobacterial
strains isolated from Africa (Senegal, Burkina Faso and Mayotte). Thanks to the contribution
of new sequences in the phylogeny of Cyanobacteria, based on 16S rDNA, we have
confirmed the polyphyly of Phormidium and Anabaena genera. To refine the relationships
among Nostocaceae family, combined analyses of 5 genes (16S rDNA, ITS-L, hetR, nifH and
rpoC1) have been done and showed that Anabaena species were distributed at least different
in 6 lineages: i/ Anabaena bergii lineage, ii/ benthic Anabaena lineage (type species A. oscillarioides),
iii/ planktonic Anabaena lineage (type species A. flos-aquae), iv/ Anabaena
sphaerica lineage, and v/ 2 lineages with Anabaena sphaerica var. tenuis. Anabaena sphaerica
var. tenuis is also a cryptic species. Moreover, our phylogenetical analyses have revealed
the rpoC1 gene transfer between one strain of Anabaena sphaerica var. tenuis and its sister
group, Cylindrospermopsis.
A physiological character, such as salt resistance, could be used to infer evolutive scenario.
This scenario showed that salt resistance is an ancestral character of Nostocaceae family,
lost independently among planktonic Anabaena lineage (type species A. flos-aquae) and
Cylindrospermopsis lineage. Furthermore, this scenario confirmed the rpoC1 gene transfer
between Anabaena sphaerica var. tenuis, salt resistant strains, and Cylindrospermopsis.
... Studies on cyanobacterial physiology (Holton et al. 1968) reveals a significant coordi-nation between the morphological complexity of species and their composition. Rippka et al. (1979) observed that biochemical diversity allowed the distinction of subgroups within several genera. ...
... which is a fundamental compound present in cell wall, results in an increased yield of oil; hence, one aspect of particular importance is the individuation of metabolic parameters for the optimal yield and mixture composition, which, in turn, depend on the strain employed. In addition to the nutritional factors, temperature (Fork et al., 1979) and light exposition (Holton et al., 1968) are also known to play a role in oil production. ...
Biodiesel is a renewable substitute for fossil diesel fuel. In order to decrease CO2 emissions coming from road transport and industrial combustions, biodiesel demand is constantly increasing, but oil crops are not able to satisfy it, and however, full replacement of diesel fuel with biodiesel coming from oil crops would not be sustainable. Microalgae are photosynthetic microorganisms that convert sunlight, water, and carbon dioxide to sugars, from which biological macromolecules, such as lipids, can be obtained. The triacylglycerol content of some microalgae is so high that they are promising sustainable feedstock for biodiesel production.
... PCC 7202 and Synechococcus cedrorum CCAP 14792. Synechococcus cedrorum (no genomic data are available) is characterized by the presence of only monounsaturated FAs (16:0 ~ 47%, 16:1 ~ 39%, and 18:1 ~ 10%) [33] [34]. The shape and morphological features of Synechococcus cedrorum resemble that of Synechococcus elongatus [34], but not Cyanobacterium stanieri PCC 7202 [28]. ...
A new cyanobacterial strain was isolated and purified from salt Lake Balkhash, Kazakhstan. According to its morphological and ultrastructural characteristics, 16S rRNA sequence and the fatty acid profile, the strain has been classified as Cyanobacterium spp. and assigned as Cyanobacterium sp. IPPAS B-1200. The strain is characterized by a non-temperature inducible Δ9-desaturation system, and by high relative amounts of myristic (14:0—30%) and myristoleic (14:1Δ9—10%) acids. The total amount of C14 fatty acids reaches 40%, which is unusually high for cyanobacteria, and it has never been reported before. The remaining fatty acids are represented mainly by palmitic (16:0) and palmitoleic (16:1Δ9) acids (the sum reaches nearly 60%). Such a fatty acid composition, together with a relatively high speed of growth, makes this newly isolated strain a prospective candidate for biodiesel production.
http://www.scirp.org/journal/PaperInformation.aspx?PaperID=51294#.VGSGHTSsWCm
... Morphological diversity is known to have a strong correlation with biochemical parameters (Holton et al. 1968).These gram-negative prokaryotes exhibit a great morphological diversity along with wide spectra of physiological properties. ...
Two strains of Nostoc commune have been isolated from the soils of two different rice-growing agro-ecosystems, viz. flat and terrace paddy fields of Dima Hasao district of the state of Assam, North-East India. Phenotypic characterization was made for both the strains and their growth, pigments (chlorophyll a, total carotenoid content and phycobiliproteins) and biochemical properties (total carbohydrate and soluble proteins) were studied. Phylogenetic comparison was made utilizing 16S rRNA gene sequences. Both strains presented higher phycocyanin content than other biliprotein pigments. Total carotenoid content (TCC) was higher in the strain isolated from flat paddy field, while the isolate from terrace paddy field was richer in phycobiliproteins. 16S rRNA gene sequences of the isolated N. commune strains were compared with available sequences of other strains of Nostoc and Anabaena from various geographical locations. Gene sequences were clustered according to their geographical origin, which also reflected the disputed taxonomic position of the Nostocacean genera Nostoc and Anabaena.
... Bacteria and blue-green algae also differ in their lipid components. Polyunsaturated fatty acids are absent from bacteria but present in most blue-green algae and eucaryotes (Erwin and Bloch, 1964;Kates, 1966;Shaw, 1966) although they are lacking in some simple blue-greens (Holton, Blecker and Stevens, 1968). ...
Background Survival of piglets poses a significant challenge in the initial days after birth because piglets are lacking readily oxidizable brown adipose tissue and born with limited amount of body reserves, which in turn limited theirthermogenic capacity. This study investigated the effects of palmitoleic acid (PA) supplementation on growth performance, maintenance of body temperature, muscle fatty acid (FA) compositions, and energy metabolism in milk replacer fed piglets. Forty-eight piglets were stratified by body weight and randomly assigned to one of four dietary treatments (0%, 1%, 2%, and 3% PA supplementation as percent of milk replacer). Piglets were weighed daily, and half in each dietary treatment groups were exposed daily to low temperature for 2 h. Plasma and tissue samples were collected at the end of the experiment for further analyses.
Results Contents of C16:1n-7 and C18:1n-7 in both plasma and liver (P < 0.001), and C16:1n-7 (P < 0.001) in semimembranosus increased linearly as PA levels increased. Most plasma FA levels (except C16:1n-7, C16:1n-9 and C22:5n-3) were lower in piglets exposed to low temperature than those that were not. Plasma glucose, triglycerides and lactate dehydrogenase levels increased linearly with PA supplementation (P< 0.001). Piglets’ average daily gain, liver weight, liver glycogen pools, and gallbladder increased linearly with PA supplementation (P < 0.05, P < 0.01, P < 0.05, and P < 0.001, respectively), but lung weight, liver nitrogen content, and body temperature drop at cold exposure decreased linearly with PA supplementation (P < 0.01, P < 0.001, and P < 0.05, respectively). Piglets exposed to low temperature had greater liver nitrogen (P < 0.05) and lactate dehydrogenase (P < 0.001) contents, but had lower liver weight (P < 0.01) and plasma lactate concentration (P< 0.05) than those that were not.
Conclusion Dietary supplementation of PA increased C16:1n-7 concentrations in plasma, liver, and semimembranosus as well as average daily gain of the piglets. The drop in body temperature of the piglet upon cold exposure decreased linearly with increasing PA supplementation.
Cyanobacteria have been known to produce lipids that are potential for biodiesel. Cyanobacteria
isolated from Indonesia are called Indonesia indigenous cyanobacteria. This study was conducted to
determine the characterization of fatty acids contained in cyanobacteria originating from Indonesia which
were isolated from 5 hot springs in Indonesia. For some 29 strains of cyanobacteria consisting of 8 genera
have performed the analysis of fatty acids (FA) by extraction method via protocol in SHERLOCK
Microbial Identification (Midi) System version 4.0, 2001 MIDI, Inc. The resulting data is as follows. All
strains of 8 genera (Synechococcus, Merismopedia, Thermosynechococcus, Stanieria, Leptolyngbia,
Westiellopsis, Mastigocladus, and Nostoc) have saturated fatty acids (SFA) and unsaturated fatty acids
(MUFA and PUFA). The content of saturated fatty acids ranged from 27.77 to 50.56%, while the content of
unsaturated fatty acids ranged from 7.58 to 63.31%. All strains have SFA Palmitic acid (16:00) which
ranges from 23.23 to 42.64%. Meanwhile, unsaturated fatty acids Palmitoleic acid (16:1 wc7) are owned by
almost all strains except Westiellopsis which range from 1.75 to 51.78%. Content of unsaturated fatty acids
Oleic acid (18: w9c) ranges from 1.43 to 35.78% mainly in Leptolyngbia, Westiellopsis, and Mastigocladus.
All strains have MUFA ranging from 7.58 to 63.31%, whereas PUFA is only owned by filamentous strains
(Leptolyngbia, Westiellposis, Mastigocladus, and Nostoc). From the results of the research can be seen that
29 strains of cyanobacteria of 8 genera have potential fatty acids as raw materials of biodiesel under certain
conditions.
Classically all algae form their cellular carbon solely from carbon dioxide by photosynthesis. However, some are facultative heterotrophs and are able to utilize organic substrates as a source of carbon. Also there are obligate heterotrophic algae which must obtain at least some organic compounds from their surroundings. For example, the colorless alga Protothecazopfii, which does not have the ability to photosynthesize, is unable to grow in the absence of organic materials (Barker, 1935). This alga utilizes ammonia, nitrogen from yeast autolyzate as well as glucose. It is unable to grow in the complete absence of yeast autolyzate.
The Cyanophyta, or blue-green algae, is a small group of primitive organisms. The cells of these algae are very simple in their structure and like the bacteria, they are said to be prokaryotic in contrast to more complex eukaryotic cellular organization found in other plants and in animals. In prokaryotic cells, the limiting membranes and therefore the discrete organelles such as the mitochondria, chloroplasts, and nuclei that are found in cells of eukaryotic organisms, are absent. The biochemical processes associated with these structures, i.e., respiration, photosynthesis, and DNA replication and RNA transcription, nevertheless go on in prokaryotic cells. The prokaryotic cell type is considered to be a very primitive evolutionary condition and this primitiveness has been confirmed by findings in recent years of fossils which look very much like present day Cyanophyta and which have been dated as being two to three billion years old. Thus there is a good evidence that the blue-green algae evolved very early in biological evolution and in fact, it has been suggested that these organisms were the first oxygen-evolving photosynthetic cells on the earth.
The development of industrial processes for large-scale production of biofuels
, in particular biodiesel
, is one of the most pursued purposes of research teams, companies, and governments all in the world, as consequence of a necessary reduction of CO2 emissions and the need of renewable
and affordable energy sources.
However, several constraints strongly limit biodiesel production, and its use, basically, is as additive blended with petrodiesel.
Microalgae
are photosynthetic microorganisms which can convert CO2 into triacylglycerols, and then, since decades, they have been considered as a potential innovative feedstock for biodiesel production, able to successfully replace oil crops.
Despite the considerable research and funding efforts, up to now biodiesel from microalgae is still an expensive process, because no significant reduction in cost of the downstream processing of biomass (biomass separation and drying and oil extraction) has been achieved.
Therefore, biodiesel production may be considered as part of a hypothetical process which produces several high-value added microalgae-based products, as pharmaceuticals or nutraceuticals.
However, research and capital investments in biodiesel production from microalgae show a positive trend up to date.
The elucidation of trophic relationships and the identification of sources and sinks of organic matter are important steps for understanding the dynamics of aquatic ecosystems (Pimm et al., 1991). The trophic relationships between aquatic organisms can be investigated in a number of ways, from the inspection of gut contents to the use of biochemical, immunological (Grisley and Boyle, 1985), and stable isotope analyses (Peterson and Fry, 1987). Some lipid species (fatty acids, fatty alcohols, hydrocarbons, and sterols) are limited to certain taxa, so if the lipid in question is metabolically stable (or retains its basic structure after consumption), it may be used to trace energy transfers through the food chain, thus helping to define predator—prey relationships.
In this study, ten isolates of freshwater filamentous heterocystous Anabaena spp. were selected for comparing their fatty acid composition with the morphological properties. Morphologically the investigated strains could be discriminated in to two groups. One important feature for specific identity of the taxa is the proximity of the akinetes to heterocyst, whether adjacent to or away from. Fatty acids and their chemo-taxonomic values were investigated in Anabaena. Totally 21 fatty acids were found all the ten isolates. A dendrogram for the ten strains are shown in relation to fatty acid composition and resulted in two major clusters. The major clusters consisted of seven strains. The other clusters had a maximum of two morphoforms. There was a close correlation between fatty acid composition and morphological characters for six species among the ten Anabaena species tested.
Depending one one’s predilections and the geological time in question, the Eras of the Phanerozoic can be properly (if informally) referred to as “the age of mammals,” “the age of angiosperms,” “the age of reptiles,” and so forth. In like manner and with equal force, the Precambrian Era, encompassing the earliest seven-eighths of geological history, can be termed “the age of blue-green algae”; microscopic cyanophytes formed the dominant component of the earth’s earliest biota (Schopf, 1970a).
The abundance and distribution of phytoplankton in the natural environment are regulated by various environmental factors, such as nutrient, light, and temperature. The effect, or stress, of each factor changes with time and space, and the relative importance of each factor also varies. Sometimes it is not difficult to identify the key factor controlling primary productivity, but quite frequently, it takes laborious efforts to discern the responsible environmental stress. This difficulty is due in good measure to the simultaneous action of more than one stress and is compounded by our general lack of understanding of the way one factor interplays with others in controlling growth.
Algae contain some characteristic substances that are usually not present in higher plants. The study of natural storage products such as carbohydrates, lipids and other organic substances may be useful also for algal phylogeny. Although studies of algal chemotaxonomy have been carried out over the years, one must still keep in mind that natural com pounds change quantitatively under various physiological states and also according to the algal strains used.
Twenty cyanobacterial cultures isolated
from different geographical regions for India
were characterized for growth and biochemical
analysis. A wide variation was observed in total
chlorophyll, total carbohydrates, total soluble
proteins, total carotenoids, NR and GS activity
among the cultures. There was a general trend of
increase in different physiological parameters
with increase in incubation time followed by decrease
on further incubation. The diversity analysis
based on similarity matrix also revealed immense
distinctness and confirmed intrageneric
variation among the cultures.
A series of fatty acids (C8–C20), both, saturated and unsaturated and sterols (C27–C29) were identified in the alga, Cyanidium caldarium, using chromatographic and spectroscopic methods. Some phylogenetic consequences of the results are discussed.
Variations in the chemical composition of sedimentary rocks and the nature of kerogen through geologic time were investigated in order to obtain information on biological and environmental evolution during the pre-Phanerozoic eon. Rock samples differing in lithology, depositional environment, and age were pulverized, pre-extracted with organic solvents, and analyzed for total nitrogen (N), phosphorus (P) and organic carbon (org. C or CT). Variations in the molecular structure of kerogen were measured by determining the ratio of org. C content after pyrolysis (CR) to org. C content before pyrolysis (CT), the ratio being considered an index of the degree of condensed-aromatic (as opposed to aliphatic) character. The rocks included mudstones (Early Archean (> 3 · 10⁹ years old) to Miocene), carbonate rocks (mid-Proterozoic (1.3 · 10⁹ years old) to Eocene), cherts (Early Archean (> 3 · 10⁹ years old) to Late Proterozoic (0.8 · 10⁹ years old)), and coal (Archean (> 2.7 · 10⁹ years old) to Early Proterozoic (∼1.8 · 10⁹ years old)).
Recent concern over increasing costs of food and particularly of animal products has kindled interest in cheaper sources of protein. Several food companies have put on the market meat substitutes made from spun soybean protein. More bizzare replacements for meat have also been suggested. Yeast and bacteria can be grown on petroleum products of waste materials. Algae and bacteria can be harvested from sewage treatment plants. Protein can be extruded from non‐edible leaves. These products nearly all contain large amounts of protein, vitamins and minerals, but some do not have as good biological value as animal protein. In addition many of these products contain toxic components which must be removed before they can serve as important dietary sources of protein for humans. Current information on these materials will be summarized and evaluated with a view towards recommendations to potential as animal protein substitutes.
A set of thirty Calothrix strains, isolated from diverse geographical regions of India, were characterised using morphological and physiological attributes. Significant differences were observed among the Calothrix strains with regard to the shape and size of trichomes and individual cells within a filament, besides the activities of the enzymes involved in nitrogen metabolism. Informative morphological and physiochemical characters have been identified that could aid in differentiation and utilisation of Calothrix strains as bioinoculants or as sources of pigments.
Fatty acids ranging from 14:0 to 18:4 were found in eleven different species of green and blue-green algae. In general, the unsaturated C18 fatty acids predominate in all the species of green algae analyzed while with some exceptions the C16 saturated acids are predominant in the blue-green algae. By the nature of their as chromatographic patterns, there appears to be no direct correlation between the fatty acids and the hydrocarbons within the same species of algae. The fatty acids are distributed in a narrower molecular weight range (C14C18) than the hydrocarbons (C15C33) and do not show any significant qualitative variations between species. All assignments of structural identities are supported by gas chromatographic and mass spectrometric data.
Hydrocarbons and fatty acids were examined from the sediments of a
marine lagoon on Surtsey, an island formed by a volcanic eruption in
1963. The distribution of both hydrocarbons and fatty acids indicated
that correlations can be made between the primary organisms observed in
the lagoon, Chlorophycophyta, and the sediment components identified.
Recent investigations have implicated a correlation between the hydrocarbon composition of algae and that found in geological sediments. This report presents information on hydrocarbon production by twelve species of algae, morphologically similar to fossil forms, including Anacystis cyanea, A. montana, Spirulina platensis, Lyngbya aestuarii, Chroococcus turgidus, Chlorella pyrenoidosa, Coelastrum microsporum, Tetraedron sp. and Scenedesmus quadricauda, along with confirmatory data on Anacystis nidulans, Nostoc sp. and Botryococcus braunii which have previously been reported. The normal hydrocarbon range is from C15 to C19 in most species, and n-C17 is predominant in all cultures. However, a few of the species show a bimodal distribution of aliphatic hydrocarbons with maxima at C17 and C27, with significant amounts of C23, C27, and C29 straight-chain olefins and paraffins. Similar bimodal distributions of saturated hydrocarbons have been observed in both tertiary and Precambrian sediments, supporting the interpretation of biological origin. The production of methyl-substituted alkanes by blue-green algae and a tentative identification of a triterpene from three species is also reported. Squalene is the only isoprenoid reported.
The effects of high and low light intensities on the ultrastructure of the large, single cells (designated as Stage IV cell types in the life cycle) of Chlorogloea fritschii grown at 45 C are described. The most noticeable difference between cells grown at 20–60 ft-c and at 700 ft-c is in the number and arrangement of the photosynthetic lamellae. In the former, the lamellae are in groups of 4–6 units, the component membranes of which are compact and, closely appressed. While the thylakoids are long, continuous, and frequently invaginated into the central cytoplasm to form concentric whorls, there is no evidence of swelling or separation to form vacuole-like structures. In contrast, in cells grown at 700 ft-c, the photosynthetic lamellae are fewer and fragmented, with the segments peripherally arranged dint frequently swollen and vesiculate. There are also differences in the, nature of the sheath, in the amount of cyanophycean starch, and in the cytoplasmic inclusions. At 20–60 ft-c, the sheath, is extensive and. fibrillar; cyanophycean starch is abundant; and cytoplasmic inclusions (e.g., and β-granules) arc sparse. At 700 ft-c the sheath is less extensive and frequently composed of short segments of fibrils and of particulate material; cyanophycean starch is sparse; and cytoplasmic inclusions are abundant.
Twenty-eight axenio planktonic cyanobacterial strains (10 Microcystis, three Oscillatoria, one Spirulina, one Aphanizomenon, 13 Anabaena) were investigated for their fatty acid composition by measurement of non-polar and hydroxy fatty acids. No 2-hydroxy fatty acids were detected in any strain, but 3-hydroxy fatty acids were detected in minor quantities in 24 strains. The highest portion of total fatty acids were non-polar fatty acids. Qualitative and quantitative analyses of 3-hydroxy fatty acids showed no taxonomic value in these strains, while the type of non-polar fatty acid composition was shown to be consistent within Microcystis and Anabaena strains, distinguishing them as type 4, characterized by the presence of 18:4, and type 2, characterized by 18:3 (α) of the Kenyon-Murata system. Two Oscillatoria agardhii Gomont strains were also included in the type 2 group due to the presence of 18: 3 (α), but the difference in characteristics of 16:2 and 16:3 between O. agardhii and Anabaena further divided type 2 into two subgroups: type 2A for Anabaena and type 2B for O. agardhii. A simplified unweighted pair group method with arithmetic averages (UPGMA) dendrogram demonstrated that the classification of 28 strains (Microcystis spp., Anabaena spp., Aphanizomenon flos-aquae (Lemmermann) Ralfs f. gracile (Lemmermann) Elenkin, O. agardhii and Spirullnasubsalsa Oersted ex Gomont based on numerical analysis of non-polar fatty acids corresponded to morphological species criteria, suggesting that non-polar fatty acid composition is a valuable chemical marker in the taxonomy of planktonic cyanobacteria. However, the fatty acid composition in Oscillatoria raciborskii is similar to that of Microcystis and very different from that of O. agardhii, suggesting its special position in Oscillatoria and the chemical diversity in the genus Oscillatoria.
The saturated long chain fatty acid methyl esters of the triglyceride fraction of Polytrichum commune spores were separated by silver nitrate TLC and identified by a combination of gas chromatographic-mass spectrometric technique. The saturated fatty acid methyl esters were straight-chained, and even-numbered with carbon numbers ranging from 12 to 26 or odd-numbered with carbon numbers ranging from 13 to 25. The major components of the fraction containing saturated fatty acid methyl esters were methyl palmitate and methyl stearate.
The fatty acid methyl esters of the monoenoic fraction isolated by silver nitrate TLC were converted to TMSO derivates which were analysed by gas chromatography-mass spectrometry. The analysis gave evidence of positional isomers. The fraction contained the following straight chain monoenoic fatty acid methyl ester isomers: methyl 7-cis-hexadecenoate, methyl 9-cis-hexadecenoate, methyl 9-cis-heptadecenoate, methyl 9-cis-octadecenoate, methyl 11-cis-octadecenoate, and methyl 11-cis-eicosenoate. The major components were methyl 9-cis-octadecenoate and methyl 7-cis-hexadecenoate.
The fatty acid spectra of 6 periphyton communities developed in laboratory streams at different combinations of light intensity and current velocity were determined by gas-liquid chromatography and silver nitrate thin-layer chromatography. Differences in species composition of the communities apparently had no striking effect on proportions of palmitic and stearic acids, whereas concentrations of myristic, palmitoleic, oleic, linoleic, and linolenic acids and a C20:5 acid were more closely related to taxonomic differences. In general, communities dominated by blue-green algae exhibited relatively high proportions of oleic, linolenic, and linolenic acids and low proportions of palmitoleic acid and a C20:5 acid, as compared to communities consisting primarily of diatoms. The data also indicated an inverse relationship between fatty acid redundancy and species diversity.
Thylakoids isolated from the purple bacterium Rhodopseudomonas spheroides were examined with regard to the amino acid composition of their structural proteid and the fatty acid composition of their ether soluble lipids. The fatty acid composition was nearly identical with that of the ether soluble lipids from whole cells. The main component was cis-vaccenic acid. Mono-unsaturated and saturated fatty acids with 18 and 16 C-atoms were dominating. After extraction of the lipids and washing of the thylakoids with NaCl and NaOH solutions, there remained at least two protein fractions and these could be separated by phenol-water at 65 °C. The amino acid composition of the structural proteid was similar to that of the structural proteids from thylakoids of Oscillatoria, Chlorella and green higher plants.
1.
The unicellular blue-green alga Chlorogloea fritschii Mitra has been isolated in pure bacteria-free culture.
2.
Evidence showing that this alga is able to fix elementary nitrogen has been obtained by determinations by the micro-Kjeldahl method of increases in total combined nitrogen in culture and also by demonstration of the uptake of elementary nitrogen in a closed culture system by measurement of nitrogen/argon ratios, with a mass-spectrometer.
3.
Studies have been made of the effects of temperature, light intensity, hydrogen ion concentration and sodium chloride concentration on growth and nitrogen fixation by the alga. At the optimum temperature of 35C cell numbers doubled in approximately 3 days during the exponential phase of growth. A considerable degree of synchronization of cell division was achieved by using combinations of light and temperature treatments.
4.
Evidence has been obtained of a close, connexion between nitrogen fixation and photosynthesis in C. fritschii. Oxygen was found to be produced by illuminated suspensions of the alga when elementary nitrogen was supplied as the only exogenous hydrogen-acceptor. No appreciable amount of nitrogen was fixed by the alga in the dark under circumstances in which considerable assimilation of nitrate-nitrogen took place. Fixation was found to be closely dependent on light intensity both in short-term and long-term experiments.
Synchronous cultures of a nitrogen-fixing blue-green alga, hitherto known as Chlorogloea fritschii but more probably an anomalous species of the genus Nostoc, were obtained by a combination of light and temperature treatments. Variation in dimensions, dry weight, pigment content and total nitrogen content of cells was followed during the development of synchronous cultures. The nitrogen-fixing activity was greatest in the small-celled filaments which develop from the endospores and predominate during exponential growth of the alga in cultures of limited volume. Strains of the alga produced by repeated exposure to X-rays, ultraviolet radiation, or sublethal concentrations of colchicine or urethane, were found to have lower rates of nitrogen fixation per unit dry weight than the original strain but liberated relatively more extracellular nitrogenous products.
Holton, Raymond W. (U. Texas, Austin.) Isolation, growth, and respiration of a thermophilic blue-green alga. Amer. Jour. Bot. 49(1): 1–6. Illus. 1962.—The isolation of a bacteria-free culture of Hapalosiphon laminosus (= Mastigocladus laminosus) from an algal mass obtained from Liard Hot Springs, British Columbia, is described. Seven different bacterial media at 2 incubation temperatures were used to test for bacteria in suspensions of partially broken up algae. The algal growth rate was obtained by calculating the slope of the straight line obtained in a plot of the cube root of the dry wt against time. In cultures aerated with air the growth was optimal between 35 and 50 C, with an upper limit at 55 and a lower limit at 25. Aeration with 1% CO2 in air significantly increased growth rates and the optimum was at 45–50 C. Unaerated flasks grew more slowly than aerated ones. The endogenous Qo2 (in μl/hr–mg dry wt) at 45 was 8.0 for growing cells and 2.8 for starved cells kept in darkness 18 hr. The Qo2 was maximal between pH 7.0 and 8.5. The concentration of phosphate buffer affected the Qo2 and rates in 0.02 M were slightly greater than those in distilled water and much greater than those in 0.4 M. The Qo2 of growing cells was slightly stimulated by 2,4-dinitrophenol (DNP), whereas glucose or glucose plus DNP did not affect it. In contrast, the endogenous Qo2 of starved cells was nearly doubled in glucose and tripled in DNP plus glucose.
Chromatophores from the green sulfur bacterium Chlorobium thiosulfatophilum strain Tassajara prepared from two different cultures contained the respective amounts of 39 and 49% ether soluble lipids, 17% protein (culture a), and 38% carbohydrates (culture a). There were 39% chlorobiochlorophyll in the chromatophore fraction (culture b). The ether soluble lipids contained long chain fatty acids with mainly 16 and 14C-atoms. The acids were saturated or mono-unsaturated. The main component was cis-palmitoleic acid. The amino acid composition of the structural proteid was determined.
Green cells of Chlorella protothecoides grown in nitrogen-rich low glucose media may be reversibly transformed to entirely chlorophyll-less cells in low nitrogen high glucose media. Photosynthetic rates and fatty ester compositions were determined during light and dark bleaching and during greening. Linolenic acid content remained unchanged during greening or bleaching. During light greening chlorophyll content and photosynthetic activity increased while oleic acid content decreased dramatically. As a result, the percent composition of linolenate appeared to parallel photosynthetic capability. Implication of α-linolenate in oxygen production, therefore, can not be based upon fatty acid percentage composition data alone.
Photosynthetic oxygen evolution per milligram of chlorophyll in Chlorella vulgaris varies with the age of the culture. The rate of oxygen evolution is low in the starting cells, it rises to a maximum after 24 hours of growth and then declines to the initial low value after 72 to 90 hours. These changes in photosynthetic competence of chlorophyll in Chlorella are paralleled by changes in α-linolenate per milligram of chlorophyll. In general the magnitude of the photosynthetic competence of chlorophyll is directly proportional to the magnitude of the ratio of α-linolenate to chlorophyll, regardless of whether high ratios are due to high α-linolenates or low chlorophyll values. This relationship holds when the cultures are grown either under continuous or intermittent illumination.
Structures and biosynthetic pathways are compared and related to physiological properties of the organisms.
The appearence and biosynthesis of unsaturated fatty acids in plants (Bacteriophyta up to Spermatophyta) is described and the results with regard to the evolutionary aspect of autotrophic and heterotrophic organisms discussed.
Thylakoide der Blaualge Oscillatoria chalybea Ktz. wurden auf ihre chemische Zusammensetzung hin untersucht. Die Prparate enthielten 44% Protein, 21% Kohlenhydrate und 17% therlsliche Lipide. Der Chlorophyllgehalt betrug 8,5%.Palmitinsure und Linolensure waren die Hauptkomponenten des Fettsurengemisches der therlslichen Lipide. Whrend in der Zelle mehr Linolensure als Palmitinsure vorkam, berwog in der Thylakoid-fraktion die Palmitinsure.Das aus den Oscillatoria-Thylakoiden gewonnene Strukturproteid besa eine hnliche Aminosurezusammensetzung wie die Strukturproteide aus den Chloroplasten der Grnalge Chlorella und hherer grner Pflanzen.Die Thylakoide der untersuchten Cyanophyceen-Art zeigen somit nicht nur morphologisch, sondern auch chemisch eine weitgehende ber-einstimmung mit Chloroplasten-Thylakoiden.The chemical composition of the thylakoids from the bluegreen alga Oscillatoria chalybea Ktz. was determined. There were 44% protein, 21% carbohydrates, and 17% ether soluble lipids in the thylakoid fraction. It contained 8.5% chlorophyll.Palmitic acid and linolenic acid were the main components among the fatty acids of the ether soluble lipids. In whole cells there was more linolenic acid than palmitic acid. In contrast palmitic acid was predominating in the thylakoid fraction.The amino acid composition of the structural proteid was quite similar to that of structural proteids of chloroplasts from the green alga Chlorella and from green higher plants.Therefore the thylakoids from Oscillatoria resemble those from chloroplasts not only with respect to their morphological structure but also with respect to their chemical composition.
The fatty acid composition of the blue-green alga, Anacystis nidulans, was investigated by gas-liquid chromatography at four different growth temperatures with illumination, aeration, cell density, medium composition, and growth rate kept constant. At all temperatures palmitic acid and a hexadecenoic acid presumed to be palmitoleic totaled approximately 90% of the fatty acids present but the ratio of the hexedecenoic to palmitic decreased as the temperature was raised. An octadecenoic and tetradecenoic (probably oleic and myristoleic, respectively) were also present and traces of a heptadecenoic acid and of others were detected. At 26°, 32°, and 35°, the ratio of total unsaturated to saturated acids remained approximately 1·0 although the qualitative composition changed, but at 41° the saturated acids predominated, the ratio being 0·7. In contrast to other algae and higher plants, polyunsaturated acids were absent in Anacystis which in this way resembles the photosynthetic bacteria.
The time is now ripe for a concerted attack on the evolutionary, ecological, and molecular aspects of life at high temperatures.
Hot springs provide nearly ideal ecosystems for such study, since they are natural environments of great antiquity and relative
constancy, where organisms have evolved to meet the environmental challenges of high temperatures. Even from our present limited
knowledge, we can draw a number of conclusions.
The distribution of chemical components in skeletal structures (cell walls), neurohormones, iodinated amino acids, sialic acid, sterols, bile salts, fatty acids, quinones, carotenoids, aldolase, glyoxylate cycle, cytochromes, DNA bases, amino acids, and phosphagens in organisms (particularly microorganisms) is described. The use of such biochemical markers in determining phylogeny and species relationships is discussed.
This chapter discusses the polyunsaturated fatty acids of microorganisms. Polyunsaturated or polyenoic fatty acids are those long-chain fatty acids that include two or more double bonds in the molecule. It is widely accepted that bacteria are incapable of synthesizing polyenoic fatty acids, and this generalization applies equally to the few genera of photosynthetic bacteria that exist. Fatty acids in a protist may occur as the result of incorporation ready-made from the environment but are more likely to be the result of de novo synthesis in the cell. The latter implies the existence of appropriate enzyme systems, which in turn implies a genetic ability to produce those enzyme systems. Study of the comparative biochemistry of fatty acid biosynthesis in protists has enabled the two leading groups of workers in this field—Erwin and Bloch and their colleagues and Korn and his coauthors—to suggest phylogenetic relationships that throw light on ancestral evolutionary pathways. Both groups have paid particular attention to the method of synthesis of oleic acid and to the ability to synthesize either or both of the positional isomers of the linolenic acid from linoleic acid.
1.(1) The major lipids of five strains of photosynthetic bacteria, Rhodopseudomonas spheroides, Rhodopseudomonas capsulata, Rhodopseudomonas palustris and Rhodopseuciomonas gelatinosa and Rhodospirillum rubrum were shown to be phosphatidyl glycerol, phosphatidyl choline, phosphatidyl ethanolamine, sulphoquinovosyl diglyceride, cardiolipin and an unidentified component, probably O-ornithyl phosphatidyl glycerol. The only lipids common to all five strains were phosphatidyl glycerol and phosphatidyl ethanolamine.2.(2) In all cases, whether grown aerobically or anaerobically, the major fatty acids were n-hexadecanoic, 9-hexadecenoic and an 11-octadecenoic acid. Rhodospirillum rubrum and Rhodopseudomonas gelatinosa contain a small amount of 9-octadecenoic acid.3.(3) Study of the biosynthesis of 11-octadecenoic acid under both dark aerobic and light anaerobic conditions showed saturated acids of a variety of chain lengths were utilised only after prior breakdown. This was demonstrated by the presence of randomised labelling in the 11-octadecenoic acid produced from specifically labelled saturated acids. The pathway of biosynthesis of the monoenoic acids is thus similar to that in non-photosynthetic anaerobic bacteria.4.(4) Both oleic and linoleic acids were also utilised, apparently after β-oxidation.5.(5) The only lipid common to all five bacteria, to green algae and plant chloroplasts is phosphatidyl glycerol.
Glycosyl glycerides have been found in substantial amounts in Chloropseudomonas ethylicum but could not be detected in two strains of Rhodopseudomonas palustris. Rhodospirillum molischianum possibly contains small amounts of monoglycosyl diglyceride. The glycolipids of C. ethylicum have been separated into two components. One of these, glycolipid I, is a monogalactosyl diglyceride. Glycolipid II, upon acid hydrolysis, yields galactose, rhamnose, and a third, unidentified sugar. The glycolipids or total lipids of the photosynthetic bacteria examined contained saturated and monounsaturated, but none of the more highly unsaturated, fatty acids.
A unialgal culture of Microcystis aeruginosa Kütz. emend. Elenkin, which is toxic when injected intraperitoneally into white mice, has been isolated. It produces a complex of symptoms similar to those which have been described for a number of toxic waterblooms. Two distinct factors seem to be present. One causes death in 4 to 48 hours preceded by symptoms of piloerection and dyspnea. It is detected only with freshly harvested cells. The other causes death within 2 to 3 hours preceded by pallor and convulsions. This second factor is an endotoxin which is detected only when cells become leaky or disintegrate. The presence of the slow-death factor tends to be obscured by the release of the fast-death factor. The concentration of the fast-death factor in the cells varies with the developmental stage of a culture and at maximum can be just as high as that of a very toxic waterbloom.A unialgal culture of Microcystis aeruginosa Kütz. emend. Elenkin, which is toxic when injected intraperitoneally into white mice, has been isolated. It produces a complex of symptoms similar to those which have been described for a number of toxic waterblooms. Two distinct factors seem to be present. One causes death in 4 to 48 hours preceded by symptoms of piloerection and dyspnea. It is detected only with freshly harvested cells. The other causes death within 2 to 3 hours preceded by pallor and convulsions. This second factor is an endotoxin which is detected only when cells become leaky or disintegrate. The presence of the slow-death factor tends to be obscured by the release of the fast-death factor. The concentration of the fast-death factor in the cells varies with the developmental stage of a culture and at maximum can be just as high as that of a very toxic waterbloom.
Analyses of the total lipids of 11 species of blue-green algae showed a simple but qualitatively variable fatty acid composition.
The species can be grouped in three categories on the basis of their oleic, linoleic, and linolenic acid content. One species
was unusual in that the ten-carbon acid accounts for one-half of its total fatty acid. Branched chain acids are absent in
the algae, but are major components of marine bacteria. The geochemical significance of the data is discussed.