Chemotaxonomic Characteristics Research Articles

Nocardia rosealba sp. nov., a novel ligninase-producing Actinobacterium isolated from soil.

A novel ligninase-producing actinomycete, designated strain NEAU-G4T, was isolated from a soil sample and subjected to a polyphasic taxonomic study to establish its status. According to 16S rRNA gene sequence comparisons, the isolate was identified as a member of the genus Nocardia, with the highest sequence similarity to Nocardia ignorata DSM 44496T (99.2 %). The whole-cell sugars contained galactose and arabinose. The amino acid of the cell wall was determined to be meso-diaminopimelic acid. The major fatty acids (>10 %) were C16 : 0, C18 : 1 ω9c, C18 : 0 and C16 : 1 ω7c. The predominant menaquinone was identified as MK-8(H6, ω-cycl). The major polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol. Strain NEAU-G4T had a draft genome size of 6 405 167 bp, annotated with 5815 protein-coding genes. The DNA G+C content was 67.6 mol%. Phylogenetic analysis using the 16S rRNA gene and whole-genome sequences showed that strain NEAU-G4T formed a stable phyletic line with N. ignorata DSM 44496T. The digital DNA-DNA hybridization and average nucleotide identity values between them were 63.7 % (60.8-66.5 %) and 95.5 %, respectively. Moreover, genomic analysis indicated that strain NEAU-G4T had the potential to degrade lignin and produce bioactive compounds. On the basis of genotypic analysis, physiological data, as well as phenotypic and chemotaxonomic characterizations, it is concluded that the organism be classified as representing a novel species of the genus Nocardia, for which the name Nocardia rosealba sp. nov. is proposed. The type strain is NEAU-G4T (=CCTCC AA 2020038T=DSM 111936T).

Mycolicibacter acidiphilus sp. nov., an extremely acid-tolerant member of the genus Mycolicibacter.

A nonmotile, facultatively anaerobic and rod-shaped bacterial strain, designated M1T was isolated from a bioreactor being operated at pH ~2 at Brisbane, Australia. Colonies appeared to be convex and white. Phylogenetic analysis of its genome revealed an affiliation with the genus Mycolicibacter and its closest species based on 16S rRNA gene analysis were Mycolicibacter algericus DSM 45454T (98.8 % similarity) and Mycolicibacter terrae CIP 104321T (98.8 %) with which strain M1T shared average nucleotide identity of 81.2 % and digital DNA-DNA hybridization similarity of 23.8 %. Strain M1T grew optimally at 0 % NaCl, at pH 6 and at between 30-33 °C. The polar lipid profile of strain M1T consisted of diphosphatidylglycerol, aminophosphoglycolipid, phosphatidylcholine, phospholipid, aminolipid, phosphoglyolipid, phosphatidylglycerol, two unidentified glycolipids and four unidentified lipids. The dominant cellular fatty acids (>10 %) were C16 : 0 and C18 : 1 ω9c and summed feature 7 (C19 : 1 ω7c and/or C19 : 1 ω6c). The DNA G+C content of strain M1T was 69.1 mol%. Based on in silico phylogenomic analysis coupled with physiological and chemotaxonomic characterizations, we classify strain M1T as representing a novel species within the genus Mycolicibacter, for which the name Mycolicibacter acidiphilus nov. is proposed. The type strain is M1T (=MCCC 1H00416T=KCTC 49392T).

Catellatospora tritici sp. nov., a novel cellulase-producing actinobacterium isolated from rhizosphere soil of wheat (Triticum aestivum L.) and emended description of the genus Catellatospora

A Gram-positive, cellulose-degrading actinobacterium, designed strain NEAU-YM18T, was isolated from rhizosphere soil of wheat (Triticum aestivum L.) sampled in Langfang, Hebei Province, PR China. The novel strain was characterized using a polyphasic approach. Morphological and chemotaxonomic characteristics confirmed that strain NEAU-YM18T belonged to the genus Catellatospora. Cells of strain NEAU-YM18T were observed to contain meso- and 3-hydroxy-diaminopimelic acids as diagnostic cell-wall amino acids. The acyl type of the cell-wall muramic acid was glycolyl. The whole-cell hydrolysates were xylose, glucose and ribose. The phospholipids consisted of diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol. The major fatty acids were iso-C15 : 0, iso-C16 : 0, C18 : 1 ω9c and summed feature 5 (anteiso-C18 : 0/C18 : 2 ω6,9c). The menaquinones were MK-9(H4), MK-9(H6) and MK-9(H2). The DNA G+C content was 71.1 %. The results of 16S rRNA gene sequence and phylogenetic analyses indicated that strain NEAU-YM18T was closely related to Catellatospora chokoriensis 2-25(1)T (98.4 % 16S rRNA gene sequence similarity), Catellatospora vulcania NEAU-JM1T (98.3%) and Catellatospora sichuanensis H14505T (98.3 %) and formed a branch with C. sichuanensis H14505T. Furthermore, the whole genome phylogeny of strain NEAU-YM18T showed that the strain formed an independent clade. The digital DNA-DNA hybridization results between NEAU-YM18T and C. chokoriensis 2-25(1)T, C. vulcania NEAU-JM1T and C. sichuanensis H14505T were 25.0, 24.7 and 24.7 %, respectively, and the whole-genome average nucleotide identity values between them were 81.5, 81.4 and 81.4 %, respectively. These genetic results and some phenotypic characteristics could distinguish strain NEAU-YM18T from its reference strains. In addition, genomic analysis confirmed that strain NEAU-YM18T had the potential to decompose cellulose and produce bioactive compounds. Therefore, strain NEAU-YM18T represents a novel species of the genus Catellatospora, for which the name Catellatospora tritici sp. nov. is proposed. The type strain is NEAU-YM18T (=CCTCC AA 2020040T=JCM 33977T).

Aeromicrobium stalagmiti sp. nov., isolated from a lava cave.

A Gram-reaction-positive, strictly aerobic, non-sporulating, non-motile, rod-shaped bacterium, designated YC3-14T, was isolated from pieces of stalagmite collected in a lava cave in Jeju, Republic of Korea. Cells showed growth at 15-35 °C, pH 6.0-9.0 and with 0-3 % (w/v) NaCl. Colonies of the cells were circular, smooth, convex and cream in colour. A 16S rRNA gene-based neighbour-joining tree indicated that the organism belonged to the genus Aeromicrobium and formed a sublineage between an Aeromicrobium endophyticum-Aeromicrobium fastidiosum cluster and an Aeromicrobium yanjiei-Aeromicrobium chenweiae cluster. The highest 16S rRNA gene similarity values of strain YC3-14T were with the type strains of A. yanjiei (99.2 %), A. endophyticum (99.1 %), A. fastidiosum (98.8 %), A. ginsengisoli (98.8 %) and A. chenweiae (98.7 %). The cell-wall peptidoglycan contained ll-diaminopimelic acid as the diagnostic diamino acid. The major menaquinone was MK-9(H4). The predominant fatty acids were C18 : 0.10-methyl, C18 : 1 ω9c and C16 : 0. The polar lipids comprised diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, an unidentified phospholipid and two unidentified lipids. The G+C content of the genome DNA was 69.9 mol%. These chemotaxonomic features of the isolate were typical for the genus Aeromicrobium. The genome-based phylogeny showed the same tree topology as the 16S rRNA gene phylogeny. The average nucleotide identity (≤84.5 %) and digital DNA-DNA hybridization (≤27.5 %) values supported that the isolate belongs to a novel species of the genus Aeromicrobium. On the basis of data obtained by a polyphasic approach, strain YC3-14T (=KCTC 49469T=NBRC 114653T) represents a novel species of the genus Aeromicrobium, for which the name Aeromicrobium stalagmiti sp. nov. is proposed.

Aurantiacibacter sediminis sp. nov., a marine bacterium isolated from a tidal flat.

A yellow-coloured bacterium, designated as strain JGD-13T, was isolated from a tidal flat in the Republic of Korea. Cells were Gram-stain-negative, aerobic, non-flagellated and rod-shaped. Growth was observed at 4-42 °C (optimum, 30 °C), at pH 6.0-12.0 (pH 7.0-8.0) and at 1-7 % (w/v) NaCl concentration (3 %). The 16S rRNA gene sequence analysis indicated that strain JGD-13T was closely related to Aurantiacibacter gangjinensis K7-2T with a sequence similarity of 98.2 %, followed by Aurantiacibacter aquimixticola JSSK-14T (98.1 %), Aurantiacibacter atlanticus s21-N3T (97.6 %), Aurantiacibacter zhengii V18T (97.6 %) and Aurantiacibacter luteus KA37T (97.5 %). The average nucleotide identity and digital DNA-DNA hybridization values with related strains were 70.3-76.2 % and 18.5-20.3 %. The genomic DNA G+C content was 60.2 mol%. Phylogenetic analysis using the maximum-likelihood method showed that strain JGD-13T formed a clade with A. aquimixticola JSSK-14T and A. gangjinensis K7-2T. The major fatty acids were summed feature 8 (39.7 %) and C17 : 1 ω6c (14.4 %). The predominant respiratory quinone was ubiquinone-10. The polar lipids were phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, one sphingoglycolipid and three unidentified lipids. On the basis of phylogenetic, phenotypic and chemotaxonomic characteristics, strain JGD-13T represents a novel species within the genus Aurantiacibacter, for which the name Aurantiacibacter sediminis JGD-13Tsp. nov. is proposed. The type strain is JGD-13T (=KCTC 72892T=KACC 21676T=JCM 33995T).

Aquirufa lenticrescens sp. nov. and Aquirufa aurantiipilula sp. nov.: two new species of a lineage of widespread freshwater bacteria

Two bacterial strains, 9H-EGSET and 15D-MOBT, were isolated from small freshwater habitats located near Salzburg, Austria. They showed the highest 16S rRNA sequence similarities of 100% and 99.9%, respectively, with type strains of species of the genus Aquirufa (Bacteroidota). Genome-based phylogenetic reconstructions with 119 amino acid sequences assigned the new taxa to the two distinct branches of the genus Aquirufa. Whole-genome average nucleotide identities were calculated with all possible pairs belonging to the genus. Values between 75.4% and 88.6% revealed that the two new strains represent each a new species. Like all, so far described members of the genus, they grew aerobically and chemoorganotrophically, were rod-shaped, red-pigmented, and motile by gliding, and showed genome sizes of about 3 Mbp and G + C values of about 40%. They could be distinguished by some phenotypic and chemotaxonomic features from their nearest related species. Until now, strain 9H-EGSET is the only one among the Aquirufa strains which contained traces of MK8 as respiratory quinone, and strain 15D-MOBT is the only one that formed tiny orange globules in liquid medium. The genome of strain 9H-EGSET comprised genes for the complete light-harvesting rhodopsin / retinal system, in the case of 15D-MOBT genes predicted for a nitrous oxide reductase were present. For the two new species of the genus Aquirufa, we propose to establish the names Aquirufa lenticrescens for strain 9H-EGSET (= JCM 34077 T = CIP 111926 T) and Aquirufa aurantiipilula for strain 15D-MOBT (= JCM 34078 T = CIP 111925 T).

Bacteroides propionicigenes sp. nov., isolated from human faeces.

An anaerobic bacterial strain, designated as NSJ-90T, was isolated from the faeces of a healthy adult in China. Cells of strain NSJ-90T were Gram-stain-negative, non-motile, non-spore-forming and rod-shaped. Based on 16S rRNA gene sequence analysis, strain NSJ-90T belonged to the genus Bacteroides and was phylogenetically closely related to Bacteroides clarus YIT 12056T (16S rRNA gene identity was 97.04 %). The DNA G+C content of strain NSJ-90T was 44.85 mol% (calculated from the genome). The average nucleotide identity between strain NSJ-90T and B. clarus YIT 12056T was 87.60 %. The major cellular fatty acids (>10 %) of strain NSJ-90T were iso-C15 : 0, anteiso-C15 : 0 and iso-C17 : 0 3-OH. Menaquinone-10 was detected as the respiratory quinone. The major products of glucose fermentation were acetic, propionic and isovaleric acids. Based on its phylogenetic, phenotypic and chemotaxonomic characteristics, we propose that strain NSJ-90T represents a novel species of the genus Bacteroides, for which the name Bacteroides propionicigenes sp. nov. is proposed. The type strain is NSJ-90T (=CGMCC 1.17886T=KCTC 25305T).

New Insights Into the Threshold Values of Multi-Locus Sequence Analysis, Average Nucleotide Identity and Digital DNA-DNA Hybridization in Delineating Streptomyces Species.

Multi-locus sequence analysis (MLSA) has been proved to be a useful method for Streptomyces identification and MLSA distance of 0.007 is considered as the boundary value. However, we found that MLSA distance of 0.007 might be insufficient to act as a threshold according to the correlations among average nucleotide identity based on MuMmer ultra-rapid aligning tool (ANIm), digital DNA–DNA hybridization (dDDH) and MLSA from the 80 pairs of Streptomyces species; in addition, a 70% dDDH value did not correspond to a 95∼96% ANIm value but approximately to 96.7% in the genus Streptomyces. Based on our analysis, it was proposed that when the MLSA distance value between a novel Streptomyces and a reference strain was < 0.008, the novel strain could be considered as a heterotypic synonym of the reference strain; when the MLSA distance value was ≥ 0.014, the novel strain could be regarded as a new Streptomyces species; when the MLSA distance value was between 0.008 and 0.014 (not included), the dDDH or ANIm value between a new strain and a reference strain must be calculated in order to determine the taxonomic status of a novel strain. In this context, a 70% dDDH or 96.7% ANIm value could act as the threshold value in delineating Streptomyces species, but if the dDDH or ANIm value was less than but close to 70 or 96.7% cut-off point, the taxonomic status of a novel strain could only be determined by a combination of phenotypic characteristics, chemotaxonomic characteristics and phylogenomic analysis.

Oceanisphaera pacifica sp. nov., isolated from the intestine of Trichiurus japonicus.

A Gram-stain-negative, strictly aerobic, non-flagellated, oxidase- and catalase-positive, rod-shaped marine bacterium, designated strain DM8T, was isolated from the intestine of Trichiurus japonicus in Weihai, China. The strain optimally grew at 25-35℃, with 1.0-4.0% (w/v) NaCl and at pH 7.0-8.0. Its colonies were circular, slightly yellow, non-transparent, smooth, and approximately 0.8-1.5mm in diameter, after being cultured for 48h on marine agar 2216. Based on the result of phylogenetic analysis of 16S rRNA gene sequence, strain DM8T had close relationship with Oceanisphaera profunda SM1222T (96.9%) and the type strain DSM 15406T of the type species Oceanisphaera litoralis (94.7%), respectively. Genome sequencing revealed a genome size of 3,109,059bp and a G + C content of 46.9mol%. It had Q-8 as the sole respiratory quinone and possessed C16:0, summed features 3 (C16:1ω7c/C16:1ω6c) and summed features 8 (C18:1ω7c/C18:1ω6c) as major fatty acids. The major polar lipid profile was composed of phosphatidylglycerol and phosphatidylethanolamine. Based on the phenotypic, chemotaxonomic characterizations, phylogenetic properties and genome analysis, strain DM8T should represent a novel species of the genus Oceanisphaera, for which the name Oceanisphaera pacifica sp. nov. is proposed. The type strain is DM8T (= KCTC 82764T = MCCC 1K06133T).

Approach to the Chemotaxonomic Characterization of Traditional Cultivation Grape Varieties through Their Varietal Aroma Profile.

In this study, the aroma profile of 12 minority grape varieties of Vitis vinifera L., included in the ‘Caiño group’, was defined along three vintages by solid phase microextraction followed by the gas chromatography–mass spectrometry method (SPME-GC-MS). Principal objectives were to assess the aromatic profile as a useful fingerprint to differentiate them, recover traditionally cultivated grape varieties for the differentiation of an important wine-growing area and discover their chemotaxonomic potential. In each variety, free and bound volatile profile was carried out by grouping varietal compounds into thirteen families. In total, 339 volatile compounds were identified, 230 as free forms and 205 as aromatic precursors. Remarkable quantitative differences were observed between aromatic profiles for terpenes in the free fraction and for C6 compounds, alcohols, sesquiterpenes and phenols in the glycosidic fraction. Principal component analysis based on their aromatic profile highlights a good differentiation between varieties and suggests a certain degree of aromatic chemotaxonomic proximity between previously known parental varieties, ‘Caiño Blanco’ with respect to ‘Caiño Bravo’ and ‘Albariño’. This study shows the preliminary results of a large research project involving a larger number of grape varieties and thus a broader spectrum of genetic relationships between them.

Description of two novel anaerobic members in the family Clostridiaceae, Anaeromonas gelatinilytica gen.nov., sp. nov., and Anaeromonas frigoriresistens sp. nov., isolated from saline lake sediment.

Cells of members of the family Clostridiaceae, phylum Firmicutes, are generally obligate anaerobic rods. Strains D2Q-14T and D2Q-11T were isolated from sediment of the saline lake Manisi in the Xinjiang Uygur Autonomous Region, PR China. In this study, we employed a polyphasic approach and whole genome analysis of the two isolates. Cells of both isolates were Gram-stain-positive rods that were motile by means of flagella and could utilize sulphate, thiosulphate, elemental sulphur and nitrate as electron acceptors. Phylogenetic analyses based on 16S rRNA gene and whole genome sequences indicated that strains D2Q-14T and D2Q-11T constituted a coherent cluster affiliated to the family Clostridiaceae. In addition, genome analysis revealed that strain D2Q-14Tharboured one nonribosomal peptide synthetase gene cluster, making up 1.4 % of the entire genome. The genome-based analysis, including average nucleotide identity, average amino acid identity and in silico DNA-DNA hybridization, biochemical, phenotypic and chemotaxonomic characterization, indicated that strains D2Q-14T and D2Q-11T represented two novel species of a novel genus in the family Clostridiaceae, for which we propose the names Anaeromonas gelatinilytica gen. nov., sp. nov. and Anaeromonas frigoriresistens sp. nov., with the type strains D2Q-14T (=KCTC 15986T=MCCC 1K04634T) and D2Q-11T (=KCTC 15985T=MCCC 1K04391T), respectively.

Pseudoneobacillus rhizosphaerae gen. nov., sp. nov., isolated from maize root rhizosphere.

A facultative anaerobic, Gram-stain-positive, endospore-forming bacterium, isolated from the rhizosphere of maize roots (Zea mays), was taxonomically studied. Based on 16S rRNA gene sequence similarity comparisons, strain JJ-79T clustered only loosely with Neobacillus species and showed the highest similarity to Neobacillus soli (97.9%). The 16S rRNA gene sequence similarities to the sequences of the type strains of other Neobacillus species were 97.5 % and below. Chemotaxonomic features supported the grouping of the strain to the Neobacillus group, e.g. the major fatty acids were C15 : 0 anteiso, C15 : 0 iso and C16 : 0, the polar lipid profile contained the major components diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and an unidentified glycolipid, the major quinone was menaquinone MK-7, and major compound in the polyamine pattern was spermidine. However, the JJ-79T genome assembly did not share most of the 11 conserved signature indels that are indicative of the genus Neobacillus. The average nucleotide identity, average amino acid identity and digital DNA-DNA hybridization values between the JJ-79T genome assembly and those of the closest relative Bacillaceae type strains were <71, <71 and <25 %, respectively. Physiological and biochemical test results were also different from those of the most closely related Bacillaceae species. As a consequence, JJ-79T represents a novel genus for which we propose the name Pseudoneobacillus rhizosphaerae gen. nov., sp. nov., with JJ-79T (=CIP 111885T=CCM 9045T) as the type strain.

Chitinophaga hostae sp. nov., isolated from the rhizosphere soil of Hosta plantaginea.

A Gram-negative, rod-shaped aerobic bacterium designated as strain 2R12T was isolated from the rhizosphere soil of Hosta plantaginea. Phylogenetic analyses based on the 16S rRNA gene revealed that strain 2R12T should be assigned to the genus Chitinophaga with the highest sequence similarity to Chitinophaga arvensicola DSM 3695T (99.1 %) and Chitinophaga ginsengisegetis DSM 18108T (98.6 %). The major fatty acids of strain 2R12T (>10 %) were iso-C15 : 0, C16 :1 ω5c and iso-C17 : 0 3-OH. The major polar lipids were phosphatidylethanolamine, two unidentified aminolipids and five unidentified lipids. The predominant respiratory quinone was MK-7. The genomic DNA G+C content was 46.1 mol%. The average nucleotide identity values of strain 2R12T with C. arvensicola DSM 3695T and C. ginsengisegetis DSM 18108T were 77.9 and 78.8 %, respectively, while in silico DNA-DNA hybridization values for strain 2R12T with these strains were 22.8 and 23.3 %, respectively. Based on comparative analysis of phylogenetic, phylogenomic, phenotypic and chemotaxonomic characteristics, strain 2R12T represents a novel species in the genus Chitinophaga, for which the name Chitinophaga hostae sp. nov. is proposed. The type strain is 2R12T (=ACCC 61757T=JCM 34719T).

Pseudomonas rustica sp. nov., isolated from bulk tank raw milk at a German dairy farm

Here we present the description of a novel Pseudomonas species, designated Pseudomonas rustica sp. nov., which was isolated from raw milk samples obtained from Germany. Results of initial 16S rRNA gene sequence analysis assigned the strain into the genus Pseudomonas and showed Pseudomonas helmanticensis, Pseudomonas neuropathica and Pseudomonas atagonensis to be its closest relatives. Further studies including sequence analysis of the rpoB gene, multi-gene phylogenetic tree reconstruction, whole-genome sequence comparisons, cellular fatty acid analysis and chemotaxonomic characterization showed a clear separation from the known Pseudomonas species. Isolate MBT-4T was closely related to Pseudomonas helmanticensis, 'Pseudomonas crudilactis' and Pseudomonas neuropathica with average nucleotide identities based on blast values of 88.8, 88.8 and 88.6%, respectively. Therefore, the strain can be classified into the Pseudomonas koreensis subgroup of the Pseudomonas fluorescens group. The G+C content of strain MBT-4T was 58.9 mol%. The strain was catalase- and oxidase-positive, while the β-galactosidase reaction was negative. Growth occurred between 4 and 30 °C and at pH values from pH 6.0 to 8.0. In conclusion, strain MBT-4T belongs to a novel species, for which the name Pseudomonas rustica sp. nov. is proposed. The type strain is MBT-4T (=DSM 112348T=LMG 32241T) and strain MBT-17 is also a representative of this species.

Sinomicrobium weinanense sp. nov., a halophilic bacterium isolated from saline-alkali soil.

A Gram-stain-negative, facultative anaerobic, non-motile, rod-shaped strain was isolated from saline-alkali soil collected in PR China, and it was designated as strain FJxsT. Its optimal growth was observed at 37-40 °C in the presence of 0-3 % (w/v) NaCl (pH 7.0). The major fatty acids of strain FJxsT were iso-C15 : 0, iso-C17 : 0 3OH, summed feature 3, C16 : 0 and iso-C15 : 1 G. The predominant respiratory quinone was menaquinone 6. The DNA G+C content of the strain was 45.18 mol%. Whole genome and 16S rRNA gene sequence analyses indicated that strain FJxsT exhibited 94.78 % sequence identity (the maximum) with Sinomicrobium soli N-1-3-6T, 94.36 % with Sinomicrobium pectinilyticum 5DNS001T, and 93.52 % with Sinomicrobium oceani SCSIO 03483T. Analyses of genotypic, phenotypic, phylogenetic and chemotaxonomic characteristics indicated that strain FJxsT represented a novel species of the genus Sinomicrobium. This novel species was named Sinomicrobium weinanense sp. nov. with its type strain as FJxsT (=CCTCC AB 2019251T=KCTC 72740T).

Chromogenicity of aerobic spore-forming bacteria of the Bacillaceae family isolated from different ecological niches and physiographic zones.

To determine the distribution patterns of pigmented bacteria of the Bacilaceae family in different physiographic zones and ecological niches, we recovered 787 isolates from 185 environmental samples (including the areas with radiation pollution). Among the strains obtained, 149 pigmented representatives were detected, which synthesized intracellular and extracellular pigments of yellow, red, pink, and dark colors. In compliance with physiological, biochemical, and chemotaxonomic features, the isolates were identified as 7 species of the Bacilaceae family. We demonstrated that the ability to synthesize pigments significantly depended on the culture medium composition. According to the color of the colonies, the absorption spectra of pigment extracts, their physicochemical properties, and the implementation of several qualitative tests, the pigmented isolates were divided into ten groups. The relative number of pigmented strains in the physiographic zone was consistent with the total level of solar radiation for the year. Most pigmented members of the Bacillaceae family were recovered from deserts and semi-deserts, and fewest of them originated from mixed forests. We show that among the studied ecological niches, pigmented strains were most often isolated from the phyllosphere and aquatic environment and least often from soils. However, the isolates from soils and aquatic environments exhibited a greater diversity of pigmentation, and a lesser variety of colored strains was obtained from the phyllosphere and the gastrointestinal tract of animals. We established that the quantitative and qualitative composition of pigmented isolates from the areas with radiation contamination differed significantly from those coming from the natural radiation background.

Hydrogenophaga crocea sp. nov. associated with cyanobacterial mat isolated from farmland mud.

A catalase and oxidase-positive strain BA0156T was isolated from a cyanobacterial mat collected from the farmland mud cultivated with sugarcane from Ahmednagar, India. The 16S rRNA gene of strain BA0156T showed the highest percent sequence similarity with Hydrogenophaga borbori LMG 30805T (98.5%), followed by H. flava DSM 619T (98.3%) and H. intermedia DSM 5680T (98.2%). The strain BA0156T contained the major fatty acids, C16:0 (25.1%) and C17:0 cyclo (3.9%), whereas phosphatidylethanolamine and diphosphatidylglycerol were the major polar lipids. The OrthoANI and dDDH values between strain BA0156T and its closest relative H. borbori LMG 30805T were 84.6% and 28.3%, respectively. The DNA G+C content of strain BA0156T was 69.4mol %. Furthermore, the biochemical and physiological features of strain BA0156T showed a distinct pattern from their closest phylogenetic neighbours. The phenotypic, genotypic and chemotaxonomic characteristics indicated that the strain BA0156T represents a new species for which the name Hydrogenophaga crocea (type strain BA0156T = MCC 3062T = KCTC 72452T = JCM 34507T) is proposed.

Nocardia albiluteola sp. nov., a novel lignin-degrading actinobacterium isolated from rhizosphere soil of pumpkin.

A novel lignin-degrading actinobacterium, designated NEAU-G5T, was isolated from pumpkin rhizosphere soil collected from field in Mudanjiang, Heilongjiang Province, northeast China, and characterized using polyphasic approach. The prior 16S rRNA gene sequence similarities and phylogenic analysis showed that strain NEAU-G5T exhibited close phylogenetic relatedness to Nocardia miyunensis NBRC 108239T (98.82 %), Nocardia nova NBRC 15556T (98.75 %), Nocardia jiangxiensis NBRC 101359T (98.68 %) and Nocardia macrotermitis RB20T (98.61 %). Morphological and chemotaxonomic characteristics indicated that strain NEAU-G5T could be assigned to the genus Nocardia. The polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, an unidentified phospholipid and an unidentified lipid. The predominant menaquinone was MK-8(H4, ω-cycl). The major fatty acids (>10 %) were identified as C16 : 0, C18 : 1 ω9c, 10-methyl C18 : 0 and C18 : 0. Mycolic acids were present. The genomic DNA G+C content of strain NEAU-G5T was 68 mol%. Moreover, based on digital DNA-DNA hybridization and average nucleotide identity values, strain NEAU-G5T could be differentiated from its reference strains. In addition, an azure B plate decolorization test and genomic analysis indicated that strain NEAU-G5T had the ability to degrade lignin. On the basis of polyphasic characteristics, strain NEAU-G5T represents a novel species of the genus Nocardia, with the name Nocardia albiluteola sp. nov. The type strain is NEAU-G5T (=CCTCC AA 2021018T=DSM 110547T).

Proteiniclasticum aestuarii sp. nov., isolated from tidal flat sediment, and emended descriptions of the genus Proteiniclasticum and Proteiniclasticum ruminis.

A novel bacterium, designated SCR006T, was isolated from tidal flat sediment from Suncheon Bay, Republic of Korea. Cells of strain SCR006T were strictly anaerobic, motile cocci, Gram-reaction-negative, and catalase- and oxidase-negative. Growth was observed at 4-41 °C (optimum, 34-37 °C), at pH 6.5-10.0 (optimum, pH 7.0-7.5) and in presence of 0-8 % NaCl (optimum, 0-2 %). Fermentation products of peptone-yeast-glucose medium were acetate and ethanol. Results of phylogenetic analyses based on 16S rRNA gene sequences indicated that strain SCR006T had high sequence similarity to Proteiniclasticum ruminis D3RC-2T (97.9 %), followed by Youngiibacter multivorans DSM 6139T (95.9 %) and Youngiibacter fragilis 232.1T (95.0 %). The average nucleotide identity value between strain SCR006T and P. ruminis DSM 24773T was 72.7 %, which strongly supported that strain SCR006T reresents a novel species within the genus Proteiniclasticum. The major cellular fatty acids are iso-C15 : 0 (27.2 %) and anteiso-C15 : 0 (16.9 %). The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, two unidentified phospholipids, an unidentified aminolipid and five unidentified lipids. The genomic size was 3.2 Mb with genomic DNA G+C content of 45.6 mol%. The results of 16S rRNA-based and genome-based phylogenetic tree analyses indicated that SCR006T should be assigned to the genus Proteiniclasticum. Strain SCR006T could be distinguished from P. ruminis D3RC-2T by its growth conditions, cell morphology and genomic characteristics. Based on the phenotypic, phylogenetic, genomic and chemotaxonomic features, strain SCR006T represents a novel species, for which the name Proteiniclasticum aestuarii sp. nov. is proposed, with the type strain SCR006T (=KCTC 25245T= JCM 34531T).

Description and genome analysis of Luteimonas viscosa sp. nov., a novel bacterium isolated from soil of a sunflower field.

Strain XBU10T was isolated from a soil sample of a sunflower plot in Inner Mongolia, China. The isolate was a Gram-stain-negative, aerobic, non-motile, rod-shaped bacterium, and its colonies were bright yellow in colour. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain XBU10T belonged to the genus Luteimonas of the family Lysobacteraceae and was most closely related to Luteimonas panaciterrae Gsoil 068T (97.8%), Luteimonas marina FR1330T (97.6%), Luteimonas aquatica RIB1-20T (97.4%) and Luteimonas huabeiensis HB2T (97.2%). Growth occurred at 4-40°C (optimum, 28-30°C), with 0-5.0% (w/v) NaCl (optimum, 0.5%) and at pH 6.0-10.0 (optimum, pH 7.0 - 8.0). The chemotaxonomic characteristics of strain XBU10T, which had Q-8 as its predominant quinone and iso-C17:1 ω9c, iso-C15:0, iso-C17:0 and iso-C16:0 as its major fatty acids, were consistent with classification in the genus Luteimonas. The polar lipid profile of strain XBU10T comprised phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, one unidentified phospholipid, two unidentified aminophospholipids and three unidentified polar lipids. The genome of strain XBU10T was 4.17 Mbp with a G + C content of 69.9%. Its genome sequence showed genes encoding alkaline phosphatase and catalase. Protein-coding genes related to carbohydrate-active enzymes were also observed. Average nucleotide identity (ANI) values between XBU10T and other species of the genus Luteimonas were found to be low (ANIm < 88.0%, ANIb < 85.0% and OrthoANIu < 85.0%). Furthermore, digital DNA-DNA hybridization (dDDH) and average amino acid identity (AAI) values between strain XBU10T and the closely related species ranged from 20.3 to 28.9% and from 64.2 to 82.3%, respectively. Based on the results of our phylogenetic, phenotypic, genotypic and chemotaxonomic analyses, it is concluded that strain XBU10T represents a novel species within the genus Luteimonas, for which the name Luteimonas viscosa sp. nov. is proposed. The type strain is XBU10T (= CGMCC 1.12158T = KCTC 23878T).