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Backscattered electron images (15 kV) of a fungal bead showing the surface of tangled mycelia (a) and the core of a freeze-cracked bead with its accumulation of microspheres at about half radius (b). X-ray digitized maps (c,d) showing the backscattered image (IM) and 6 elements as indicated. In these images only porous beads were observed.
Source publication
SEM including X-ray mapping and energy dispersive
X-ray microanalysis (EDX) were used
to demonstrate the mechanism of uptake of
copper ions by the fungus Penicillium ochrochiloron.
Smooth and porous microspheres
(10-40 μm diameter) appeared within the
core of fungal mycelia beads after 1-4 days of
incubation in medium with 100 mg/lCu2+.
SEM and EDX...
Contexts in source publication
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... mycelia of fungal beads consists of cells linked together with considerable branching, forming a vast network of fibers (Figs 1 and 2). In the presence of Tween 80 in liquid culture, these fibers condense to form spheres (Fig 2a) which grow in size at the rate of about 1 mm in diameter per day in culture. Freeze cracking allowed the hollow interior of beads to be examined (Fig 1a). Surprisingly, small micros- pheres 20-40 µm in diameter were seen throughout the core (Fig 2b-d) with a dense array of those objects appearing at around half radius (Fig 2b). Two forms of beads were actually observed, one rather porous and numerous, and another exhibiting a smooth surface but less numerous. Using backscat- tered electron imaging or BEI mode, and adjusting contrast and brightness of the image appropriately, the structures rich in one or more high Z (atomic number) atoms stood out magnificently (Fig 2b). X-ray mapping of one section (Fig 2d, IM) showed that the brightest regions were especially rich in Cu and P with a strong EDX signal for Mg, Ca, Cl and K appear- ing as well (Fig 2 c,d). Beads with smooth sur- The corresponding EDX analysis of the microsphere shown in Fig 3 . The lower spectrum, illustrating that copper is the dominant ele- ment, was taken at a point near the center of the microsphere. The upper EDX analysis was derived from cupric oxalate pre- pared in this laboratory. faces were rich in Cu but no other major ele- ment, suggesting that the counter anion is organic since the detector was rather insensi- tive for C and O (Fig 3). Since some Penicillium species are known to produce oxalate [5,6] it might be that copper (cupric) oxalate was also formed during the four days of incubation. In fact EDX spectra of copper phosphate and oxalate salts prepared in this laboratory pre- sented very similar results with those of porous and smooth surface microspheres ...
Context 2
... mycelia of fungal beads consists of cells linked together with considerable branching, forming a vast network of fibers (Figs 1 and 2). In the presence of Tween 80 in liquid culture, these fibers condense to form spheres (Fig 2a) which grow in size at the rate of about 1 mm in diameter per day in culture. Freeze cracking allowed the hollow interior of beads to be examined (Fig 1a). Surprisingly, small micros- pheres 20-40 µm in diameter were seen throughout the core (Fig 2b-d) with a dense array of those objects appearing at around half radius (Fig 2b). Two forms of beads were actually observed, one rather porous and numerous, and another exhibiting a smooth surface but less numerous. Using backscat- tered electron imaging or BEI mode, and adjusting contrast and brightness of the image appropriately, the structures rich in one or more high Z (atomic number) atoms stood out magnificently (Fig 2b). X-ray mapping of one section (Fig 2d, IM) showed that the brightest regions were especially rich in Cu and P with a strong EDX signal for Mg, Ca, Cl and K appear- ing as well (Fig 2 c,d). Beads with smooth sur- The corresponding EDX analysis of the microsphere shown in Fig 3 . The lower spectrum, illustrating that copper is the dominant ele- ment, was taken at a point near the center of the microsphere. The upper EDX analysis was derived from cupric oxalate pre- pared in this laboratory. faces were rich in Cu but no other major ele- ment, suggesting that the counter anion is organic since the detector was rather insensi- tive for C and O (Fig 3). Since some Penicillium species are known to produce oxalate [5,6] it might be that copper (cupric) oxalate was also formed during the four days of incubation. In fact EDX spectra of copper phosphate and oxalate salts prepared in this laboratory pre- sented very similar results with those of porous and smooth surface microspheres ...
Context 3
... mycelia of fungal beads consists of cells linked together with considerable branching, forming a vast network of fibers (Figs 1 and 2). In the presence of Tween 80 in liquid culture, these fibers condense to form spheres (Fig 2a) which grow in size at the rate of about 1 mm in diameter per day in culture. Freeze cracking allowed the hollow interior of beads to be examined (Fig 1a). Surprisingly, small micros- pheres 20-40 µm in diameter were seen throughout the core (Fig 2b-d) with a dense array of those objects appearing at around half radius (Fig 2b). Two forms of beads were actually observed, one rather porous and numerous, and another exhibiting a smooth surface but less numerous. Using backscat- tered electron imaging or BEI mode, and adjusting contrast and brightness of the image appropriately, the structures rich in one or more high Z (atomic number) atoms stood out magnificently (Fig 2b). X-ray mapping of one section (Fig 2d, IM) showed that the brightest regions were especially rich in Cu and P with a strong EDX signal for Mg, Ca, Cl and K appear- ing as well (Fig 2 c,d). Beads with smooth sur- The corresponding EDX analysis of the microsphere shown in Fig 3 . The lower spectrum, illustrating that copper is the dominant ele- ment, was taken at a point near the center of the microsphere. The upper EDX analysis was derived from cupric oxalate pre- pared in this laboratory. faces were rich in Cu but no other major ele- ment, suggesting that the counter anion is organic since the detector was rather insensi- tive for C and O (Fig 3). Since some Penicillium species are known to produce oxalate [5,6] it might be that copper (cupric) oxalate was also formed during the four days of incubation. In fact EDX spectra of copper phosphate and oxalate salts prepared in this laboratory pre- sented very similar results with those of porous and smooth surface microspheres ...
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... mycelia of fungal beads consists of cells linked together with considerable branching, forming a vast network of fibers (Figs 1 and 2). In the presence of Tween 80 in liquid culture, these fibers condense to form spheres (Fig 2a) which grow in size at the rate of about 1 mm in diameter per day in culture. Freeze cracking allowed the hollow interior of beads to be examined (Fig 1a). Surprisingly, small micros- pheres 20-40 µm in diameter were seen throughout the core (Fig 2b-d) with a dense array of those objects appearing at around half radius (Fig 2b). Two forms of beads were actually observed, one rather porous and numerous, and another exhibiting a smooth surface but less numerous. Using backscat- tered electron imaging or BEI mode, and adjusting contrast and brightness of the image appropriately, the structures rich in one or more high Z (atomic number) atoms stood out magnificently (Fig 2b). X-ray mapping of one section (Fig 2d, IM) showed that the brightest regions were especially rich in Cu and P with a strong EDX signal for Mg, Ca, Cl and K appear- ing as well (Fig 2 c,d). Beads with smooth sur- The corresponding EDX analysis of the microsphere shown in Fig 3 . The lower spectrum, illustrating that copper is the dominant ele- ment, was taken at a point near the center of the microsphere. The upper EDX analysis was derived from cupric oxalate pre- pared in this laboratory. faces were rich in Cu but no other major ele- ment, suggesting that the counter anion is organic since the detector was rather insensi- tive for C and O (Fig 3). Since some Penicillium species are known to produce oxalate [5,6] it might be that copper (cupric) oxalate was also formed during the four days of incubation. In fact EDX spectra of copper phosphate and oxalate salts prepared in this laboratory pre- sented very similar results with those of porous and smooth surface microspheres ...
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... mycelia of fungal beads consists of cells linked together with considerable branching, forming a vast network of fibers (Figs 1 and 2). In the presence of Tween 80 in liquid culture, these fibers condense to form spheres (Fig 2a) which grow in size at the rate of about 1 mm in diameter per day in culture. Freeze cracking allowed the hollow interior of beads to be examined (Fig 1a). Surprisingly, small micros- pheres 20-40 µm in diameter were seen throughout the core (Fig 2b-d) with a dense array of those objects appearing at around half radius (Fig 2b). Two forms of beads were actually observed, one rather porous and numerous, and another exhibiting a smooth surface but less numerous. Using backscat- tered electron imaging or BEI mode, and adjusting contrast and brightness of the image appropriately, the structures rich in one or more high Z (atomic number) atoms stood out magnificently (Fig 2b). X-ray mapping of one section (Fig 2d, IM) showed that the brightest regions were especially rich in Cu and P with a strong EDX signal for Mg, Ca, Cl and K appear- ing as well (Fig 2 c,d). Beads with smooth sur- The corresponding EDX analysis of the microsphere shown in Fig 3 . The lower spectrum, illustrating that copper is the dominant ele- ment, was taken at a point near the center of the microsphere. The upper EDX analysis was derived from cupric oxalate pre- pared in this laboratory. faces were rich in Cu but no other major ele- ment, suggesting that the counter anion is organic since the detector was rather insensi- tive for C and O (Fig 3). Since some Penicillium species are known to produce oxalate [5,6] it might be that copper (cupric) oxalate was also formed during the four days of incubation. In fact EDX spectra of copper phosphate and oxalate salts prepared in this laboratory pre- sented very similar results with those of porous and smooth surface microspheres ...
Context 6
... mycelia of fungal beads consists of cells linked together with considerable branching, forming a vast network of fibers (Figs 1 and 2). In the presence of Tween 80 in liquid culture, these fibers condense to form spheres (Fig 2a) which grow in size at the rate of about 1 mm in diameter per day in culture. Freeze cracking allowed the hollow interior of beads to be examined (Fig 1a). Surprisingly, small micros- pheres 20-40 µm in diameter were seen throughout the core (Fig 2b-d) with a dense array of those objects appearing at around half radius (Fig 2b). Two forms of beads were actually observed, one rather porous and numerous, and another exhibiting a smooth surface but less numerous. Using backscat- tered electron imaging or BEI mode, and adjusting contrast and brightness of the image appropriately, the structures rich in one or more high Z (atomic number) atoms stood out magnificently (Fig 2b). X-ray mapping of one section (Fig 2d, IM) showed that the brightest regions were especially rich in Cu and P with a strong EDX signal for Mg, Ca, Cl and K appear- ing as well (Fig 2 c,d). Beads with smooth sur- The corresponding EDX analysis of the microsphere shown in Fig 3 . The lower spectrum, illustrating that copper is the dominant ele- ment, was taken at a point near the center of the microsphere. The upper EDX analysis was derived from cupric oxalate pre- pared in this laboratory. faces were rich in Cu but no other major ele- ment, suggesting that the counter anion is organic since the detector was rather insensi- tive for C and O (Fig 3). Since some Penicillium species are known to produce oxalate [5,6] it might be that copper (cupric) oxalate was also formed during the four days of incubation. In fact EDX spectra of copper phosphate and oxalate salts prepared in this laboratory pre- sented very similar results with those of porous and smooth surface microspheres ...
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... electron microscopy coupled with EDX analysis showed that under suitable con- ditions in culture copper precipitates extracel- lularly and is held within the mycelial matrix of Penicillium ochro-chloron fungal beads. Below pH 5 copper hydroxide does not precipitate when copper is at 100 mg/l [7]. The porous spherical complexes are most likely copper phosphate since X-ray mapping (Fig 2) shows that Cu, P and O are the predominant ele- ments. Depending on how long the beads have been challenged in copper containing media, the number of these microspheres decreased over time. The most abundant number of spheres was found in samples taken after approximately 20 to 25 hours of copper challenge. The reason for the reduc- tion in the number of porous intermycelial spheres is not known but some condition in the medium after 24 hours is sufficiently dif- ferent that the solubility product for copper(II) phosphate must favor dissolution. Since pH of the bulk phase remains between 4.0 +/-0.2 during the uptake experiments it is not believed that more precise control of this vari- able is needed to prevent dissolution of the copper salts. Several fungi are known to pro- duce oxalic acid as a secondary metabolite and since copper oxalate is quite insoluble (K sp = 4.43 x 10 -10 ) [ 8] it is also not surprising to find this salt deposited within fungal mycelia as smooth microspheres. Copper phosphate is not soluble in the bulk solution at pH 4 either (K sp = 1.40 x 10 -37 ) [8] at the concentrations used in our media suggesting that the condi- tions for its precipitation within the mycelial core differ from those of the bulk phase. It is indeed possible that an increase in phosphate anion concentration exists for a period of time in the core of the mycelial bead. Such a con- dition could be brought about by loss of cell viability due to anoxia and release of organophosphates from the cytoplasm into the core by dying or physiologically compro- mised cells. Then, acid phosphatases in the periplasm of the cells [6,9] could hydrolyze the organophosphates presenting the inward diffusing copper ions with an increase in phos- phate anion and a condition that favors pre- cipitation. A similar argument can be made for copper oxalate precipitation [6]. EDX analysis was also performed on carbon coated preparations of cupric phosphate and cupric oxalate prepared in our laboratory. The simi- larities of these EDX spectra with those obtained from the spherical precipitates also confirms that the smooth microspheres are probably copper oxalate and the porous pre- cipitate is copper phosphate. Indeed, smooth copper oxalate spheres of sub-micrometer dimensions have been reported to form dur- ing non-biological mediated precipitation [10] and lead phosphate precipitates have been observed when fungi were challenged with that metal [11]. Copper oxalate is most likely produced by viable cells as a detoxification process carried out in P. ochro-chloron through the action of the enzyme oxaloac- etase. Oxalate is released from the cells and forms a precipitate with copper when the K sp is ...
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The results of the study of human aortic walls, subjected to different stages of mineralization are presented. By means of scanning electron microscopy and X-ray microanalysis the morphology, elemental composition and characteristics of the mineral component localization were investigated. The key differences in the initial, intermediate and final...
Citations
... Metalphosphates formation have also been described as a by-product of fungal weathering of minerals containing toxic metals. Phosphate salts with uranium (Fomina et al. 2008), lead (Liang et al. 2015), and copper (Crusberg 2004) have all been observed in fungal microcosm experiments. Finally, clays have also been reported as secondary minerals during soil formation in association with fungal activity. ...
Biochemical weathering · Biomechanical weathering · Biominerals · Geomycology · Symbioses · Mycelial network
... This indicates that copper tolerant Trichoderma isolates have the potential to deploy mechanisms to tolerate copper so that their growth could continue unhindered in the presence of copper. Similarly, several mechanisms responsible for metal toxicity tolerance have been described by earlier researchers (Gadd and Griffith 1980;Subramanyam et al. 1983;Gadd 1993;Crusberg 2004). Copper tolerance mechanism in Penicillium ochrochloron was reported mainly due to binding and trapping of copper to the cell wall with phosphate and oxalate salts outside the mycelia that led to reduced uptake of copper (Crusberg 2004). ...
... Similarly, several mechanisms responsible for metal toxicity tolerance have been described by earlier researchers (Gadd and Griffith 1980;Subramanyam et al. 1983;Gadd 1993;Crusberg 2004). Copper tolerance mechanism in Penicillium ochrochloron was reported mainly due to binding and trapping of copper to the cell wall with phosphate and oxalate salts outside the mycelia that led to reduced uptake of copper (Crusberg 2004). Cell wall polymers such as chitin (Subramanyam et al. 1983) or melanin can bind metal ions to the fungal cell wall or can be precipitated outside hyphae (Gadd and Griffith 1980). ...
Present research was conducted to understand the characteristics of Trichoderma in the development of combination product involving a lower dose of Cu fungicide that showed promise in the effective management of Phytophthora infestans, the late blight pathogen of potato. Based on Cu tolerance activity, potential Trichoderma strains (viz., TCMS-36, SBIT-32 and TCMS-71) were selected. Electron microscopy (SEM and TEM) studies revealed that tolerant Trichoderma isolates (SBIT-32 and TCMS 36) accumulated Cu on the cell wall, while the sensitive isolate (TCMS 71) was repressed due to penetration of Cu through the cell wall. To elucidate Cu-tolerance, Cu-biosorption by living and dead mycelia of T. asperellum was estimated by atomic absorption spectrophotometer. Both sensitive and tolerant T. asperellum isolates accumulated Cu in their cells all through the observation period of 120 h, with considerable increase in the amount of Cu removed from the cell free supernatant from 24 to 120 h. Isolate TCMS-36 recorded maximum Cu accumulation (0.3506 mg/g) in living mycelia, while SBIT-32 recorded highest accumulation (0.2368 mg/g) in dead mycelia. Effectiveness of Cu tolerant T. asperellum was studied in combination with Cu fungicides; viz., COC (Blitox-50), COH (Kocide) in controlling late blight disease in the field. Among three modes of applications, viz., seed, foliar and seed+foliar, maximum delay in progress of the disease was recorded in seed+foliar application. Dual combination of COC@500 ppm and Trichoderma was found more effective than COC alone @1000 ppm in reducing disease severity. Cu tolerant Trichoderma strains could thus be developed as combination products with Cu-based fungicides for safe and effective management of late blight disease of potato.
... .9H 2 O, AgNO 3 , AuCl 4 H aq., Cd(NO 3 ) 2 .4H 2 O, Co(NO 3 ) 2 .6H 2 O, Cr(NO 3 ) 3 .9H 2 O, Cu(NO 3 ) 2 .3H 2 O, HgCl 2 , Ni(NO 3 ) 2 .6H 2 O, Pb(NO 3 ) 2 , TiCl 3 , U(CH 3 COO) 2 .2H 2 O and Zi(NO 3 )2.6H 2 O. Stock solutions of required concentrations were prepared in ultra-pure de-ionized water below the solubility limit of the metal salts. ...
Here we describe a unique microbial biotechnology for simultaneous bioremediation and biomining of twelve ionic metals overcoming the obstacles of multimetal toxicity to microbes. After a thorough search of key microorganisms in microbiomes of many sulfidic springs in Bavaria (Germany) over an area of 200 km2, we found three new strains EH8, EH10 and EH11 of Mucor hiemalis physiologically compatible and capable of multimetal-remediation and enrichment. We combined the multimetal-resistance, hyper-accumulation and elicitation power of EH8, EH10 and EH11 to develop a novel biotechnology for simultaneous removal, fractionation and enrichment of metal ions. As a first step we showed the intracellular fixing and deposition of mercury as nanospheres in EH8’s sporangiospores. Scanning Electron Microscopy-Energy-Dispersive X-Ray analysis revealed binding and precipitation of other applied metal ions as spherical nano-particles (~50–100 nm) at the outer electro-negative cellwall-surface of EH8, EH10 and EH11 sporangiospores. Microbiomes, germinated spores and dead insoluble cellwalls of these strains removed >81–99% of applied Al, Cd, Co, Cr, Cu, Hg, Ni, Pb, U, and Zn simultaneously and furthermore enriched precious Ag, Au and Ti from water all within 48 h, demonstrating the potential of new biotechnologies for safe-guarding our environment from metal pollution and concentrating precious diluted, ionic metals.
... A recent study mentions an Ascomycota, Purpureocillium lilacinum, as being involved in the biomineralization of jarosite, a peculiar type of sulphur and iron mineral formed in acidic conditions, through its metabolic activity [64]. Biomineralization of phosphate minerals as a result of fungal activity has also been documented recently [65][66][67][68][69]. All are typical examples of BIM, confirming the fact that fungi are also important players in microbial biomineralization. ...
In the field of microbial biomineralization, much of the scientific attention is focused on processes carried out by prokaryotes, in particular bacteria, even though fungi are also known to be involved in biogeochemical cycles in numerous ways. They are traditionally recognized as key players in organic matter recycling, as nutrient suppliers via mineral weathering, as well as large producers of organic acids such as oxalic acid for instance, an activity leading to the genesis of various metal complexes such as metal-oxalate. Their implications in the transformation of various mineral and metallic compounds has been widely acknowledged during the last decade, however, currently, their contribution to the genesis of a common biomineral, calcite, needs to be more thoroughly documented. Calcite is observed in many ecosystems and plays an essential role in the biogeochemical cycles of both carbon (C) and calcium (Ca). It may be physicochemical or biogenic in origin and numerous organisms have been recognized to control or induce its biomineralization. While fungi have often been suspected of being involved in this process in terrestrial environments, only scarce information supports this hypothesis in natural settings. As a result, calcite biomineralization by microbes is still largely attributed to bacteria at present. However, in some terrestrial environments there are particular calcitic habits that have been described as being fungal in origin. In addition to this, several studies dealing with axenic cultures of fungi have demonstrated the ability of fungi to produce calcite. Examples of fungal biomineralization range from induced to organomineralization processes. More examples of calcite biomineralization related to direct fungal activity, or at least to their presence, have been described within the last decade. However, the peculiar mechanisms leading to calcite biomineralization by fungi remain incompletely understood and more research is necessary, posing new exciting questions linked to microbial biomineralization processes.
... Fungi also have the potential of using phosphorus in metal bioprecipitation. Penicillium ochro-chloron showed an ability to precipitate cupric oxalate together with porous microspheres of cupric phosphate (Crusberg 2004), while Penicillium cyclopium removed up to 95% supplied lead in the presence of phosphate (Tsekova et al. 2006). Rhee et al. (2012Rhee et al. ( , 2014aRhee et al. ( , 2014b demonstrated fungal mediation of pyromorphite (Pb 5 (PO 4 ) 3 Cl) formation from lead metal in the laboratory and in environmental locations. ...
Yeasts can exhibit various mechanisms that effect changes in metal speciation, toxicity and mobility. This research has examined the role of yeast phosphatases in lead bioprecipitation when utilizing an organic phosphorus-containing substrate as the sole phosphorus source. The formation of lead-containing biominerals after growth with organic phosphorus sources (glycerol 2-phosphate, phytic acid) was demonstrated and it was found that test yeasts were capable of mediating precipitation of lead phosphate (Pb 3 (PO 4) 2), pyromorphite (Pb 5 (PO 4) 3 Cl), anglesite (PbSO 4), and the lead oxides massicot and litharge (PbO), with variations in the mineral types produced between the different species. All test yeasts produced pyromorphite, and most produced anglesite. Lead oxides were only detected with Pichia acacia. Lead-containing precipitates were also formed if yeast cells were pre-grown in organic-phosphorus-containing media and subsequently exposed to Pb(NO 3) 2. The role of phosphatases in mediating the formation of lead-containing minerals has provided further understanding of potential fungal roles in metal and mineral biogeochemistry as well as the possible significance of these mechanisms for element biorecovery or bioremediation.
... Formation of metal phosphates has been observed in fungi, e.g. Penicillium ochrochloron precipitated cupric oxalate and cupric phosphate (Crusberg, 2004), whereas Penicillium cyclopium removed up to 95% supplied lead in the presence of phosphate (Tsekova et al., 2006). Rhee and colleagues (2012;2014a,b) have shown fungal mediation of pyromorphite (Pb 5(PO4)3Cl) formation from lead metal. ...
Geoactive soil fungi were examined for their ability to release inorganic phosphate (Pi ) and mediate lead bioprecipitation during growth on organic phosphate substrates. Aspergillus niger and Paecilomyces javanicus grew in 5 mM Pb(NO3 )2 -containing media amended with glycerol 2-phosphate (G2P) or phytic acid (PyA) as sole P sources, and liberated Pi into the medium. This resulted in almost complete removal of Pb from solution and extensive precipitation of lead-containing minerals around the biomass, confirming the importance of the mycelium as a reactive network for biomineralization. The minerals were identified as pyromorphite (Pb5 (PO4 )3 Cl), only produced by P. javanicus, and lead oxalate (PbC2 O4 ), produced by A. niger and P. javanicus. Geochemical modelling of lead and lead mineral speciation as a function of pH and oxalate closely correlated with experimental conditions and data. Two main lead biomineralization mechanisms were therefore distinguished: pyromorphite formation depending on organic phosphate hydrolysis and lead oxalate formation depending on oxalate excretion. This also indicated species specificity in biomineralization depending on nutrition and physiology. Our findings provide further understanding of lead geomycology and organic phosphates as a biomineralization substrate, and are also relevant to metal immobilization biotechnologies for bioremediation, metal and P biorecovery, and utilization of waste organic phosphates.
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... In this study, the mycelia of T. atroviride was deep blue in color in broth culture at all concentrations of Cu due to binding of Cu to the fungal cell wall (Anand et al. 2006). Crusberg (2004) and Zapotoczny et al. (2006) similarly reported the formation of blue colored mycelia in the presence of Cu in Penicillium ochro-chloron and A. pinkertoniae. In this study, T. atroviride hyphae showed scattered shapes at all concentrations of Cu. ...
Isolated Trichoderma atroviride from Cu-polluted river sediment at the Serdang Industrial Area was studied under in vitro conditions to understand the mechanisms that allowed the fungi to thrive in the Cu-polluted freshwater ecosystem. From this study, adsorption was recognized as the main mechanism of Cu tolerance with 50–85% adsorption during the in vitro experiment. The uptake capacity of the isolate in liquid medium ranged from 0.8 to 11.2 mg g−1 in the potato dextrose broth medium with increasing Cu concentrations from 25 to 300 mg L−1. It was found that 2.7–5.0% of Cu was lost due to washing. The high percentage of Cu adsorption and the high uptake capacity of Cu by T. atroviride suggest that it is a potential bioremediator of Cu. However, further studies are needed to confirm its practical use as a bioremediating agent for Cu under field conditions.
... Certain fungi (ex. Penicillium ochro-chloron) are resistant to Cu to the point of being able to grow in an electroplating bath, where Cu levels excess 5000 mg/l (Crusberg, 2004). A. pinkertoniae seems to belong to the group of highly tolerant fungi, being also much more tolerant than the other fungi isolated from the similar habitats. ...
... The metals were usually bound to the fungal cell wall (Townsley, 1985; Gadd, 1993), or precipitated outside hyphae. This type of tolerance was described in P. ochro-chloron, in which copper was found to be entrapped in phosphate and oxalate salts outside the mycelia (Crusberg, 2004). Further mechanisms concerning copper, as reviewed by Cervantes and Guitierrez-Corona (1994), include binding to the cell wall, reduced uptake and extraor intra-cellular chelation. ...
Acremonium pinkertoniae isolated from zinc wastes was studied to understand the mechanisms that allow living organisms to thrive in polluted environments and the possible role of the fungus in the redistribution and cycling of copper. The fungus was cultured on solid media supplemented with copper sulfate at increasing concentrations. At high doses it was observed that the mycelia acquired a characteristic blue color. This was accompanied by morphological changes and the formation of crystalloid structures within thickened cell walls. The material was further analysed with EDX, X-ray powder diffraction and IR spectroscopy. It was demonstrated that A. pinkertoniae is able to accumulate over 20% dry weight of copper by what probably is a chitin-glucan complex.
Nitrogen is an essential and incredibly versatile element for living organisms. In agriculture, nitrogen is a key element to understand soil and aquatic pollution, very often associated with heavy metal pollution. In this chapter, we overview the correlations between nitrogen and copper pollution, mediated by antimicrobial compounds used in agriculture. Plant Growth-Promoting Microorganisms (PGPM) are a heterogeneous group of microorganisms ranging from Bacteria (PGPBs) to Archaea and Fungi, which can modulate plant growth by conferring direct and indirect benefits, such as phytohormone production and stress alleviation. Many of these microorganisms are tolerant to high concentrations of Copper, increasing plant productivity even under metallic stress. We suggest the use of bacterial and fungal species associated with plant species for the bioremediation of degraded soil and water bodies, alarm about the bioaugmentation of copper through economically relevant plants, and review plant and microbial species applied to bioremediation.
