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Sphingobacterium composti sp. nov., a novel DNase-producing bacterium isolated from compost
Abstract
A Gram-negative, strictly aerobic, nonmotile, and nonspore-forming bacterial strain, designated T5-12T, was isolated from compost and characterized using a polyphasic taxonomical approach. The isolate was positive for catalase and oxidase tests. It could degrade DNA, but was negative for degradation of macromolecules such as casein, collagen, starch, chitin, cellulose, and xylan. The DNA G+C content was 36.0 mol%. The predominant isoprenoid quinone was menaquinone 7 (MK-7). The major fatty acids were iso-C15:0 (45.6%), iso-C17:0 3OH (17.2%), and summed feature 4 (C16:1 ω7c and/or iso-C15:0 2OH, 14.9%). Comparative 16S rRNA gene sequence analysis showed that strain T5-12T fell within the radiation of the cluster comprising members of the genus Sphingobacterium. Strain T5-12T exhibited lower than 94% of 16S rRNA gene sequence similarity with respect to the type strains of recognized Sphingobacterium species. On the basis of its phenotypic properties and phylogenetic distinctiveness, strain T5-12T (=KCTC 12578T=LMG 23401T=CCUG 52467T) should be classified in the genus Sphingobacterium as the type strain of a novel species, for which the name Sphingobacterium composti sp. nov. is proposed.
... After Sanger sequencing of the 16S rRNA gene, genome sequencing Kb22 T was carried out. According to the comparisons with the complete 16S rRNA gene sequences in the EzBioCloud database, the highest level of sequence similarity occurred to Sphingobacterium nematocida M-SX103 T (94.39 %) [14], followed by Sphingobacterium composti T5-12 T (94.31 %) [15]. ...
... Anaerobic and microaerophilic growth was checked on tryptic soy agar (TSA) medium using the Anaerocult A and C systems (Merck). The physiological characteristics were examined by side-by-side analysis with S. composti T5-12 T [15]. ...
A Gram-reaction-negative bacterial strain, designated Kb22 T , was isolated from agricultural soil and characterized using a polyphasic approach to determine its taxonomic position. On the basis of 16S rRNA gene sequence analysis, the strain shows highest similarity (94.39 %) to Sphingobacterium nematocida M-SX103 T . The highest average nucleotide identity value (71.83 %) was found with Sphingobacterium composti T5-12 T , and the highest amino acid identity value (66.65 %) was found with Sphingobacterium olei HAL-9 T . Cells are aerobic, non-motile rods. The isolate was found to be positive for catalase and oxidase tests. The assembled genome of strain Kb22 T has a total length of 4,06 Mb, the DNA G+C content is 38.1 mol%. The only isoprenoid quinone is menaquinone 7 (MK-7). The major fatty acids are iso-C 15:0 (28.4%), summed feature 3 (C 16:1 ω7 c and/or iso-C 15:0 2-OH) (25.7 %) and iso-C 17:0 3-OH (19.7 %). Based on phenotypic characteristics and phylogenetic results, it is concluded that strain Kb22 T is a member of the genus Sphingobacterium and represents a novel species for which the name Sphingobacterium hungaricum sp. nov. is proposed. The type strain of the species is strain Kb22 T (=LMG 31574 T =NCAIM B.02638 T ).
... Ten et al. described a novel prokaryotic species within the genus Sphingobacterium under the specific name Sphingobacterium composti in 2006 [2]. This name was included on the 'Validation list no. ...
As required by Rule 54 of the International Code of Nomenclature of Prokaryotes, the authors propose the replacement specific epithet ‘allocomposti’ for the illegitimate prokaryotic name Sphingobacterium composti Yoo et al. 2007, the replacement subspecific epithet ‘bovistauri’ for Mycobacterium chelonae subsp. bovis Kim et al. 2017 and the replacement subspecific epithet ‘allosunkii’ for Lactobacillus delbrueckii subsp. sunkii Kudo et al. 2012. Meanwhile, new combinations Christiangramia oceanisediminis and Christiangramia crocea are also proposed as replacements for the illegitimate prokaryotic names Gramella oceanisediminis Yang et al. 2023 and Gramella crocea Zhang et al. 2023, respectively.
... All strains are negative for lysine decarboxylase, ornithine decarboxylase, urease and tryptophan deaminase activities. MK-7 is the major menaquinone for all strains ?, Positive; -, negative; w, weakly positive a Data were from Ten et al. (2006); b Data were from Verena et al. (2012) replicates for all three methods. Distance matrices for the neighbour-joining and maximum-likelihood analyses were calculated using Kimura's two-parameter model (Kimura 1980). ...
... The temperature of the compost in group T was higher than that in group CK; it is possible that the high temperature killed most of the Acinetobacter that competed with lignin-degrading bacteria, thereby improving the degradation of lignin in group T. In addition, Sphingobacterium is not conducive to the degradation of crude fiber, 45 and its existence also impedes the degradation of crude fiber in CMR. The average relative abundance of Sphingobacterium in group CK was 11.6% over the first 3 days of composting, while the relative abundance of Sphingobacterium in group T decreased from 28.4% to 3.6% on Day 1 of composting and was almost 0% on Day 3 of composting, which showed that the high temperature in group T effectively inactivated Sphingobacterium. ...
The objective of this study was to investigate the impact of thermophilic bacteria on crude fiber content, carbohydrate-active enzyme (CAZyme) genes, and associated microbial communities during Chinese medicine residues composting. The study examines changes over 15 days of composting with (T) and without (CK) thermophilic microbial agents. Results show that the group T compost temperature reached a maximum of 71.0 °C and remained above 70 °C for 2 days, while the group CK maximum temperature was only 60.9 °C. On Day 15, the seed germination index (GI) of group T reached 98.7%, while the group CK GI was only 56.7%. After composting, the degradation rates of cellulose, hemicellulose, and lignin in group T increased by 5.1, 22.5, and 18.5%, respectively, compared to those in group CK. Thermophilic microbial agents changed the microbial communities related to CAZymes, increasing unclassified_o_Myxococcales and Sphaerobacter abundance and reducing Acinetobacter and Sphingobacterium abundance. Thermophilic microbial agents also increased the abundance of the GT4, GT2_Glycos_transf_2, and AA3 gene families. These results show that thermophilic microbial agents can increase composting temperature, accelerate compost maturation, and promote crude fiber degradation. Therefore, they have broad application potential.
... Sphingobacterium spp. are ubiquitous in nature, being found in soil (27,28) and compost or activated sludge (29,30), and also sometimes from clinical specimens (31). Most Sphingobacterium species are Gram-negative, nonfermenting, non-spore-forming, rod-shaped bacteria, and there are 24 species of Sphingobacterium that are currently recognized (32). ...
Sphingobacterium sp. is a yellowish Gram-negative bacterium that is usually characterized by high concentrations of sphingophospholipids as lipid components. As microbial enzymes have been in high demand in industrial fields in the past few decades, this study hopes to provide significant information on lipase activities of Sphingobacterium sp., since limited studies have been conducted on the Sphingobacterium sp. lipase. A microbe from one collected Artic soil sample, ARC4, was identified as psychrotolerant Sphingobacterium sp., and it could grow in temperatures ranging from 0°C to 24°C. The expression of Sphingobacterium sp. lipase was successfully performed through an efficient approach of utilizing mutated group 3 late embryogenesis abundant (G3LEA) proteins developed from Polypedilum vanderplanki. Purified enzyme was characterized using a few parameters, such as temperature, pH, metal ion cofactors, organic solvents, and detergents. The expressed enzyme is reported to be cold adapted and has the capability to work efficiently under neutral pH (pH 5.0 to 7.0), cofactors like Na⁺ ion, and the water-like solvent methanol. Addition of nonionic detergents greatly enhanced the activity of purified enzyme.
IMPORTANCE The mechanism of action of LEA proteins has remained unknown to many; in this study we reveal their presence and improved protein expression due to the molecular shielding effect reported by others. This paper should be regarded as a useful example of using such proteins to influence an existing expression system to produce difficult-to-express proteins.
... The anti-SMASH server was used to identify the secondary metabolite biosynthesis gene clusters (Blin et al. 2019). Comparative genome analysis for Sphingobacterium pedocola Ka21 T , Sphingobacterium alkalisoli Y3L14 T (Xu et al. 2017), Sphingobacterium olei HAL-9 T (Liu et al. 2020) and Sphingobacterium composti DSM 18850 T (Yoo et al. 2007, later homonym of Sphingobacterium composti T5-12 T (Ten et al. 2006)) was performed by OrthoVenn2 webserver (https://orthovenn2.bioinfotoolkits.net/) (Xu et al. 2019). ...
A Gram-reaction-negative halotolerant bacterial strain, designated Ka21 T , was isolated from agricultural soil and characterised using a polyphasic approach to determine its taxonomic position. On the basis of 16S rRNA gene sequence analysis, highest similarity was found with Sphingobacterium alkalisoli Y3L14 T (96.72%). Cells were observed to be aerobic, non-motile rods. The isolate was found to be able to grow between 0 and 10% of NaCl concentration. The assembled genome of strain Ka21 T has a total length of 5.2 Mb with a G + C content of 41.0 mol%. According to the genome analysis, Ka21 T encodes several glycoside hydrolases that may play a role in the degradation of accumulated plant biomass in the soil. Based on phenotypic characteristics and phylogenetic analysis, it is concluded that strain Ka21 T represents a novel species in the Sphingobacterium genus for which the name Sphingobacterium pedocola sp. nov. is proposed. The type strain of the species is strain Ka21 T (= LMG 31575 T = NCAIM B.02636 T ).
... The description is as before (Ten et al., 2006) with the following modification. The G+C content of the type-strain genome is 46.8%, its approximate size 4.39 Mbp, its IMG deposit 2700988711. ...
Although considerable progress has been made in recent years regarding the classification of bacteria assigned to the phylum Bacteroidetes, there remains a need to further clarify taxonomic relationships within a diverse assemblage that includes organisms of clinical, piscicultural, and ecological importance. Bacteroidetes classification has proved to be difficult, not least when taxonomic decisions rested heavily on interpretation of poorly resolved 16S rRNA gene trees and a limited number of phenotypic features. Here, draft genome sequences of a greatly enlarged collection of genomes of more than 1,000 Bacteroidetes and outgroup type strains were used to infer phylogenetic trees from genome-scale data using the principles drawn from phylogenetic systematics. The majority of taxa were found to be monophyletic but several orders, families and genera, including taxa proposed long ago such as Bacteroides, Cytophaga, and Flavobacterium but also quite recent taxa, as well as a few species were shown to be in need of revision. According proposals are made for the recognition of new orders, families and genera, as well as the transfer of a variety of species to other genera. In addition, emended descriptions are given for many species mainly involving information on DNA G+C content and (approximate) genome size, both of which can be considered valuable taxonomic markers. We detected many incongruities when comparing the results of the present study with existing classifications, which appear to be caused by insufficiently resolved 16S rRNA gene trees or incomplete taxon sampling. The few significant incongruities found between 16S rRNA gene and whole genome trees underline the pitfalls inherent in phylogenies based upon single gene sequences and the impediment in using ordinary bootstrapping in phylogenomic studies, particularly when combined with too narrow gene selections. While a significant degree of phylogenetic conservation was detected in all phenotypic characters investigated, the overall fit to the tree varied considerably, which is one of the probable causes of misclassifications in the past, much like the use of plesiomorphic character states as diagnostic features.
Two novel bacterial strains, designated as DN00404 T and DN04309 T , were isolated from aquaculture water and characterized by using a polyphasic taxonomic approach. Cells of strains DN00404 T and DN04309 T were Gram-stain-negative, aerobic, non-motile, oxidase-positive and catalase-positive. Cells of DN00404 T were short rod-shaped and those of DN04309 T were long rod-shaped. Strain DN00404 T was found to grow at 15–37 °C (optimum, 25–30 °C), at pH 6.0–11.0 (optimum, pH 7.5) and in 0–2.0 % (w/v) NaCl (optimum, 1.0 %). Strain DN04309 T was found to grow at 15–45 °C (optimum, 20–37 °C), at pH 5.5–11.0 (optimum, 7.5) and in 0–4.0 % (w/v) NaCl (optimum, 0.5 %). Phylogenetic analyses based on 16S rRNA gene and genome sequences revealed that the two strains belonged to the genus Sphingobacterium and were distinct from all known species of this genus. The average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) values between the two strains and between each of the two strains and related type strains of this genus were well below the recognized thresholds of 95.0–96.0 % ANI and 70.0 % dDDH for species delineation. The genomic DNA G+C contents of strains DN00404 T and DN04309 T were 41.6 and 36.0 mol%, respectively. The respiratory quinone in both strains was identified as MK-7, and their major fatty acids were iso-C 15 : 0 and summed feature 3 (C 16 : 1 ω 6 c and/or C 16 : 1 ω 7 c ), which were similar to those of other species of this genus. The two major fatty acids C 16 : 0 and iso-C 17 : 0 3-OH were also found in strain DN00404 T . Based on genotypic and phenotypic characteristics, two novel species of the genus Sphingobacterium are proposed: Sphingobacterium micropteri sp. nov. with DN00404 T (=GDMCC 1.1865 T =KACC 21924 T ) as the type strain and Sphingobacterium litopenaei sp. nov. with DN04309 T (=GDMCC 1.1984 T =KCTC 82348 T ) as the type strain.
Nine paddy straw-degrading microbial consortia were isolated from 253 paddy straw samples from northern China and the Yangtze River Valley, which are two major rice production regions in China. The microbial consortia completely degraded filter paper within 15 d at 25 °C. The V4 region of the microbial consortia 16S rRNA gene was amplified, and the amplicons were sequencing using the Illumina Miseq high-throughput platform. Compilobacterota and Bacteroidota were the predominant phyla in the samples. At the genus level, the relative abundance of Macellibacteroides was the highest in Y2, and Arcobacter was predominant in the other samples. Analysis of the microbial community structure revealed that the diversity and richness in samples from the Yangtze River Valley were significantly higher compared with those of the samples from northern China, and the community structure of the four microbial consortia from the northern region had higher similarity than the five consortia from the Yangtze River Valley.
A Gram-stain-negative, non-motile and rod-shaped bacterium, designated strain 5.0403-2T, was isolated from a cave soil sample collected from Tiandong Cave, Guizhou Province, south-west PR China. Cells showed positive oxidase and catalase reactions. The predominant isoprenoid quinone was MK-7. The major fatty acids were identified as iso-C15 : 0, summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c), iso-C17 : 0 3OH and summed feature 9 (iso-C17 : 1 ω9c or C16 : 0 10-methyl). The cellular polar lipids contained phosphatidylethanolamine, one unidentified phospholipid, three unidentified phosphoglycolipids and four unidentified lipids. The genomic DNA G+C content was 36.0 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain 5.0403-2T should be assigned to the genus Sphingobacterium. Results of 16S rRNA gene sequence similarity analysis showed that strain 5.0403-2T was most similar to Sphingobacterium bovisgrunnientis KCTC 52685T (98.7 %), Sphingobacterium composti KCTC 12578T (98.0 %) and Sphingobacterium alimentarium DSM 22362T (97.3 %) and less than 95.0 % similar to other species of the genus Sphingobacterium. The average nucleotide identity values between strain 5.0403-2T and S. bovisgrunnientis KCTC 52685T, S. composti KCTC 12578T and S. alimentarium DSM 22362T were 94.2, 82.3 and 77.2 % respectively. The digitalDNA-DNA hybridization values between strain 5.0403-2T and S. bovisgrunnientis KCTC 52685T, S. composti KCTC 12578T and S. alimentarium DSM 22362T were 68.4, 25.6 and 20.7 %. These results indicated that the isolate represented a novel genomic species. The polyphasic taxonomic characteristics indicated that strain 5.0304-2T represents a novel species of the genus Sphingobacterium, for which the name Sphingobacterium cavernae sp. nov. (type strain 5.0403-2T=KCTC 62981T=CCTCC AB 2019257T) is proposed.
Seventeen strains of Cytophaga, Flavobacterium and Actinobacillus species were taxonomically characterized. DNA base composition of these strains ranged from 39.0 to 42.3 mol%, and the menaquinone system was MK-7. All the strains contained sphingolipids with long-chain bases, which are characteristic of the genus Sphingobacterium. Based on their chemotaxonomic and physiological characteristics together with DNA/DNA hybridization studies, we propose two new species and two new combinations, Sphingobacterium faecium sp. nov., Sphingobacterium piscium sp. nov., Sphingobacterium heparinum comb. nov., Sphingobacterium thalpophilum comb. nov. and two genospecies of the genus Sphingobacterium. Flavobacterium yabuuchiae was found to be a synonym of Sphingobacterium spiritivorum.
Gliding motility, ultrastructure and nutrition of two newly isolated filamentous sulfate-reducing bacteria, strains 5ac10 and 4be13, were investigated. The filaments were always attached to surfaces. Growth was supported by addition of insoluble aluminium phosphate or agar as substrata for gliding movement. Electron microscopy of ultrathin sections revealed cell walls characteristic of Gramnegative bacteria; the undulated structure of the outer membrane may pertain to the translocation mechanism. Intracytoplasmic membranes were present. Acetate, higher fatty acids, succinate or fumarate served as electron donors and carbon sources. Strain 5ac10 grew also with lactate, but not with benzoate that was used only by strain 4be13. Strain 5ac10 was able to grow slowly on H2 plus CO2 or formate in the presence of sulfate without additional organic carbon source. The capacity of complete oxidation was shown by stoichiometric measurements with acetate plus sulfate. Both strains contained b- and c-type cytochromes. Desulfoviridin was detected only in strain 5ac10. The two filamentous gliding sulfate reducers are described as new species of a new genus, Desulfonema limicola and Desulfonema magnum.
CLUSTAL X is a new windows interface for the widely-used progressive multiple sequence alignment program CLUSTAL W. The new
system is easy to use, providing an integrated system for performing multiple sequence and profile alignments and analysing
the results. CLUSTAL X displays the sequence alignment in a window on the screen. A versatile sequence colouring scheme allows
the user to highlight conserved features in the alignment. Pull-down menus provide all the options required for traditional
multiple sequence and profile alignment. New features include: the ability to cut-and-paste sequences to change the order
of the alignment, selection of a subset of the sequences to be realigned, and selection of a sub-range of the alignment to
be realigned and inserted back into the original alignment. Alignment quality analysis can be performed and low-scoring segments
or exceptional residues can be highlighted. Quality analysis and realignment of selected residue ranges provide the user with
a powerful tool to improve and refine difficult alignments and to trap errors in input sequences. CLUSTAL X has been compiled
on SUN Solaris, IRIX5.3 on Silicon Graphics, Digital UNIX on DECstations, Microsoft Windows (32 bit) for PCs, Linux ELF for
x86 PCs, and Macintosh PowerMac.
With its theoretical basis firmly established in molecular evolutionary and population genetics, the comparative DNA and protein
sequence analysis plays a central role in reconstructing the evolutionary histories of species and multigene families, estimating
rates of molecular evolution, and inferring the nature and extent of selective forces shaping the evolution of genes and genomes.
The scope of these investigations has now expanded greatly owing to the development of high-throughput sequencing techniques
and novel statistical and computational methods. These methods require easy-to-use computer programs. One such effort has
been to produce Molecular Evolutionary Genetics Analysis (MEGA) software, with its focus on facilitating the exploration and
analysis of the DNA and protein sequence variation from an evolutionary perspective. Currently in its third major release,
MEGA3 contains facilities for automatic and manual sequence alignment, web-based mining of databases, inference of the phylogenetic
trees, estimation of evolutionary distances and testing evolutionary hypotheses. This paper provides an overview of the statistical
methods, computational tools, and visual exploration modules for data input and the results obtainable in MEGA.
Screening was performed to isolate cellulose-producing microorganisms from the Korean traditional fermented persimmon vinegar. The resulting strain, KJ 145T, was then taxonomically investigated by phenotypic characterization, particularly chemotaxonomic, and by phylogenetic inference based on a 16S rDNA sequence analysis including other related taxa. Strain KJ 145T was found to grow rapidly and form pale white colonies with smooth to rough surfaces on a GYC agar. Strain KJ 145T also produced acetate from ethanol, and was tolerable to 10% ethanol in SM medium. In a static culture, a thick cellulose pellicle was produced, and in GYC broth, the strain grew at temperatures ranging from 28 to 40°C with an optimum pH of 4.0. The genomic DNA G+C content of strain KJ 145T was 61.9 mol%, and the predominant ubiquinone was Q10 as the major quinone and Q9 as the minor quinone. The major cellular fatty acids were C16:0 and the sum in feature 7 (C18:1 w9c, w12t and/or w7c). A 16S rRNA-targeted oligonucleotide probe specific for strain KJ 145T was constructed, and the phylogenetic position of the new species was derived from a 16S rDNA-based tree. When comparing the 16S rDNA nucleotide sequences, strain KJ 145T was found to be most closely related to G. hansenii LMG 1527T (99.2%), although KJ 145T was still distinct from G. hansenii LMG 1527T and G. xylinus LMG 1515T in certain phenotypic characteristics. Therefore, on the basis of 16S rDNA sequences and taxonomic characteristics, it is proposed that strain KJ 145T should be placed in the genus Gluconacetobacter as a new species, Gluconacetobacter persimmonis sp. nov., under the type-strain KJ 145T (=KCTC =10175BPT=KCCM=l0354T).
Fitch, W. M. (Dept. of Physiological Chemistry, Univ. of Wisconsin, Madison, Wisconsin, 53706), 1971. Toward defining the course of evolution: minimum change for a specific tree topology. Syst. Zool., 20:406-416.A method is presented that is asserted to provide all hypothetical ancestral character states that are consistent with describing the descent of the present-day character states in a minimum number of changes of state using a predetermined phylogenetic relationship among the taxa represented. The character states used as examples are the four messenger RNA nucleotides encoding the amino acid sequences of proteins, but the method is general.
Seventeen strains corresponding to Flavobacterium spiritivorum, seven strains corresponding to or received as Sphingobacterium mizutae, and the type strains of Flavobacterium multivorum and Flavobacterium thalpophilum were examined for deoxyribonucleic acid-deoxyribonucleic acid relatedness. Duplicate cultures of the type strains and of some of the S. mizutae field strains, from various sources, were included to make a total of 43 cultures examined. Of the 17 F. spiritivorum strains, 15 could be included in that species, but 2 constituted a closely related, but separate, species. For this new species we propose the name Fhvobacterium yabuuchiae, with strain FSOSl (= NCTC 12113) as the type strain. Only three strains could be included in S. mizutae; of the four remaining strains, one represented a separate species 32% related to S. mizutae, one corresponded to Flavobacterium meningosepticum, and the classification of the other two was unresolved. The type strains of F. multivorum and F. thalpophilum were distinct from the other cultures studied. The new combination Flavobacterium mizutaii is also proposed.
The recently-developed statistical method known as the "bootstrap" can be used to place confidence intervals on phylogenies. It involves resampling points from one's own data, with replacement, to create a series of bootstrap samples of the same size as the original data. Each of these is analyzed, and the variation among the resulting estimates taken to indicate the size of the error involved in making estimates from the original data, In the case of phylogenies, it is argued that the proper method of resampling is to keep all of the original species while sampling characters with replacement, under the assumption that the characters have been independently drawn by the systematist and have evolved independently. Majority-rule consensus trees can be used to construct a phylogeny showing all of the inferred monophyletic groups that occurred in a majority of the bootstrap samples. If a group shows up 95% of the time or more, the evidence for it is taken to be statistically significant. Existing computer programs can be used to analyze different bootstrap samples by using weights on the characters, the weight of a character being how many times it was drawn in bootstrap sampling. When all characters are perfectly compatible, as envisioned by Hennig, bootstrap sampling becomes unnecessary; the bootstrap method would show significant evidence for a group if it is defined by three or more characters.
Growth yields were determined with Acetobacterium woodii strain NZva 16 on hydrogen and CO2, formate, methanol, vanillate, ferulate and fructose in mineral medium in the absence and presence of 0.05% yeast extract. Yeast extract was not essential for growth but enhanced growth yields by 25–100% depending on the substrate fermented. Comparison of yields on formate or methanol allowed calculation of an energy yield in the range of 1.5–2 mol ATP per mol acetate formed during homoacetate fermentation of A. woodii. In the presence of 6 mM caffeate, growth yields were determined with the substrates formate or methanol. Caffeate was reduced to hydrocaffeate and increased growth yields were obtained. An ATP yield of about 1 mol per mol of caffeate reduced was calculated. Cytochromes were not detectable in cell free extracts or membrane preparations.
A plate assay based on the visible solubilization of small substrate particles and the formation of haloes on Petri dishes, containing a mixture of different dye-labelled polysaccharides as substrates, provides a specific, reliable and rapid simultaneous detection of corresponding polysaccharide-degrading microorganisms. It has potential for increasing the efficacy of screening of microorganisms, utilizing different polysaccharides, in large numbers of natural samples. Diversely colored insoluble forms of amylose, xylan and hydroxyethyl-cellulose (HE-cellulose) were prepared as chromogenic substrates by using the cross-linking reagent 1,4-butanediol diglycidyl ether and the dyes Brilliant Red 3B-A, Cibacron Blue 3GA and Reactive Orange 14. Using the method, the bacteria with amylase or xylanase or cellulase or a combination of these activities were screened from soil and sludge samples, selected and identified according to 16S rDNA sequencing.