Peptidoglycan Amino Acids Research Articles

Cellulomonas xiejunii sp. nov., Cellulomonas chengniuliangii sp. nov. and Cellulomonas wangsupingiae sp. nov., three cellulolytic bacteria isolated from intestinal contents of Marmota himalayana.

Six facultative anaerobic, Gram-stain-positive, oxidase-negative, rod-shaped bacteria (strains zg-B89T, zg-B12, zg-Y338T, zg-Y138, zg-Y908T and zg-Y766), were isolated from the intestinal contents of Marmota himalayana in Qinghai Province, PR China. The 16S rRNA gene sequence analysis showed that zg-B89T showed highest similarity to Cellulomonas iranensis NBRC 101100T (99.5 %), zg-Y338T to Cellulomonas cellasea DSM 20118T (98.7 %), and zg-Y908T to Cellulomonas flavigena DSM 20109T (99.0 %). Phylogenetic and phylogenomic analysis based on 16S rRNA gene and 881 core genes revealed that these six strains formed three separate clades in the genus Cellulomonas. Average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between these three novel species and all members of the genus Cellulomonas were below species thresholds (95-96 % for ANI and 70 % for dDDH). The DNA G+C contents of zg-B89T, zg-Y338T and zg-Y908T were 73.6, 72.9 and 74.5 %, respectively. Strains zg-B89T and zg-Y908T had anteiso-C15 : 0, C16 : 0 and anteiso-C15 : 1 A, and zg-Y338T had anteiso-C15 : 0, C16 : 0 and iso-C16 : 0 as the main fatty acids. All novel type strains had MK-9 (H4) as the predominant respiratory quinone, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and phosphatidylinositol mannoside as the major polar lipids, and rhamnose, ribose and glucose as the cell-wall sugars. The peptidoglycan amino acids of zg-B89T, zg-Y338T and zg-Y908T contained ornithine, alanine, glutamic acid and aspartic acid (except for zg-Y338T). Based on genotypic, phenotypic, phylogenetic and biochemical properties, the six uncharacterized strains represent three novel species in the genus Cellulomonas, for which the names Cellulomonas xiejunii sp. nov. (type strain zg-B89T=GDMCC 1.2821T=KCTC 49756T), Cellulomonas chengniuliangii sp. nov. (type strain zg-Y338T=GDMCC 1.2829T=KCTC 49754T) and Cellulomonas wangsupingiae sp. nov. (type strain zg-Y908T=GDMCC 1.2820T=KCTC 49755T) are proposed, respectively.

Characterization of isolates of members of the genus Actinomyces from Marmota himalayana: description of Actinomyces faecalis sp. nov., Actinomyces respiraculi sp. nov., and Actinomyces trachealis sp. nov.

Six novel strains (ZJ34T, ZJ561, ZJ750T, ZJ1629, zg-993T and zg-987) isolated from faeces and respiratory tracts of Marmota himalayana from the Qinghai-Tibet Plateau of PR China were characterized comprehensively. The results of analyses of the 16S rRNA gene and genome sequences indicated that the six strains represent three novel species of the genus Actinomyces, and are closely related to Actinomyces urogenitalis DSM 15434T (16S rRNA gene sequences similarities, 94.9-98.7 %), Actinomyces weissii CCUG 61299T (95.6-96.6 %), Actinomyces bovis CCTCC AB2010168T (95.7 %) and Actinomyces bowdenii DSM 15435T (95.2-96.4 %), with values of digital DNA-DNA hybridization less than 30.1 % when compared with their closest relatives but higher than 70 % within each pair of novel strains (ZJ34T/ZJ561, ZJ750T/ZJ1629 and zg-993T/zg-987). All the novel strains had C18 : 1 ω9c and C16 : 0 as the two most abundant major fatty acids. MK-9(H4) or MK-8(H4) was the sole or predominant respiratory quinone of strains ZJ34T, ZJ750T and zg-993T and their polar lipid profiles differed, but all had diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, and phosphatidyl inositol mannoside as major components. ZJ750T shared identical peptidoglycan amino acid profile with ZJ34T (alanine, glutamic acid, lysine and ornithine) and the same whole-cell sugar composition with zg-993T (glucose, rhamnose and ribose). Strain zg-993T contained alanine, aspartic acid, glutamic acid, glycine and lysine in the peptidoglycan, and the only sugar in ZJ34T was ribose. The DNA G+C contents of the novel strains were within the range of 65.8-70.1 mol%. On the basis of the results from the aforementioned analyses, the six novel strains were classified as representing three novel species of genus Actinomyces, for which the names Actinomyces faecalis sp. nov. [type strain ZJ34T (=GDMCC 1.1952T=JCM 34355T)], Actinomyces respiraculi sp. nov. [type strain ZJ750T (=GDMCC 1.1950T=JCM 34356T)] and Actinomyces trachealis sp. nov. [type strain zg-993T (=GDMCC 1.1956T=JCM 34357T)] were proposed, respectively.

Agromyces laixinhei sp. nov. isolated from bat feces in China.

Three rod-shaped, Gram-stain-positive, and catalase-positive, phenotypically closely related isolates (HY052T, HY050, and HY045) were obtained from fecal samples collected from bats in Guangxi province and Chongqing city of China. Circular, smooth, light-yellow colonies appeared on brain heart infusion plate after 24–48 h incubation at 28°C. The optimal pH for growth was between 6.0 and 7.5. Based on 16S rRNA, the three isolates were phylogenetically related to Agromyces terreus DS-10T, Agromyces aureus AR33T, Agromyces salentinus 20-5T, Agromyces allii UMS-62T, Agromyces lapidis CD55T, and Agromyces italicus CD1T. Moreover, based on 296 core genes, the phylogenomic tree indicated that the three isolates clustered together, closest to Agromyces cerinus VKM Ac-1340T and Agromyces fucosus VKM Ac-1345T but separated distantly from other Agromyces species. The average nucleotide identity values between strain HY052T and other Agromyces species ranged from 79.3% to 87.9%, lower than the 95–96% threshold. Furthermore, the genome of strain HY052T contains a circular chromosome of 3,437,203 bp with G + C content of 69.0 mol%. Main fatty acids were anteiso-C15:0 and anteiso-C17:0. The polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, and unidentified glycolipids. Rhamnose, ribose, and glucose were the primary cell wall sugars. The major peptidoglycan amino acids included alanine, glutamic acid, glycine, and 2,4-diaminobutyric acid. An additional remarkable difference from other Agromyces species is that MK-12 was the sole menaquinone in strain HY052T. Based on results from the polyphasic characterizations performed in this study, our isolates are proposed to be members of a novel species in genus Agromyces, named Agromyces laixinhei. The type strain is HY052T (= CGMCC 1.17175T = JCM 33695T).Electronic Supplementary MaterialSupplementary material is available for this article at 10.1007/s12275-021-0546-5 and is accessible for authorized users.

Ornithinibacillus caprae sp. nov., a moderate halophile isolated from the hides of a white goat.

A novel Gram-stain-positive, motile, moderate halophile, strain L9T, was isolated from hides of white goat in China. The isolate grew optimally at 30°C, at pH 7 and with 5-10% (w/v) NaCl. The predominant menaquinone was MK-7, and the major cellular fatty acids were identified as iso-C15:0 and anteiso-C15:0. The peptidoglycan amino acid type was determined to be A4β, containing L-ornithine and D-aspartic as diagnostic amino acids. The phospholipids were dominated by diphosphatidylglycerol, phosphatidylglycerol, one unidentified aminophospholipid and two unidentified phospholipids. Genome sequencing resulted in a genome size of 4.0 Mbp and a DNA G + C content of 35.9mol%. Phylogenetic trees based on the 16S rRNA gene sequences showed the isolate to be closely related to Oceanobacillus limi H9BT (98.2% similarity) and Ornithinibacillus halophilus G8BT (97.5% similarity). The ANI and dDDH values between strain L9T and the closely related species were 69.8-76.1% and 13.0-20.5%, respectively. On the basis of the data presented, strain L9T represents a novel species of the genus Ornithinibacillus, for which the name Ornithinibacillus caprae sp. nov. is proposed. The type strain is L9T (= KCTC 43176T = CGMCC 1.17659T).

Ktedonosporobacter rubrisoli gen. nov., sp. nov., a novel representative of the class Ktedonobacteria, isolated from red soil, and proposal of Ktedonosporobacteraceae fam. nov.

A novel filamentous, spore-forming, Gram-stain-positive bacterium, designated SCAWS-G2T, was isolated from red soil in Jiangxi Province, PR China. The strain grew at 25-45 °C and at pH 4.0-7.0, and was able to tolerate up to 50 mM Zn2+. The complete genome of strain SCAWS-G2T was a circular chromosome of ~11.34 Mb, which contained four 16S rRNA genes with three sequence types (0.4-0.8 % differences). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain SCAWS-G2T formed a distinct lineage within the order Ktedonobacterales, showing <89.2 % sequence similarities to the recognized taxa of this order. The whole-genome based phylogenomic tree separated strain SCAWS-G2T from the recognized families within Ktedonobacterales. The genome-wide average nucleotide identity values between strain SCAWS-G2T and the related type strains were <68.2 %. The strain can also be differentiated from the recognized families by a number of phenotypic characteristics. The polar lipids of SCAWS-G2T were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, seven unidentified glycolipids and one unidentified lipid. The peptidoglycan amino acids contained ornithine, glycine, glutamic acid and alanine, and the cell-wall sugars were mainly galactose and rhamnose. The major fatty acids were C16 : 1 2-OH, C16 : 0 and iso-C17 : 0. Based on all these data, we propose that strain SCAWS-G2T represents a novel genus and species, Ktedonosporobacter rubrisoli gen. nov., sp. nov., within the new family Ktedonosporobacteraceae fam. nov. of the order Ktedonobacterales. The type strain of Ktedonosporobacter rubrisoli is SCAWS-G2T (=CGMCC 1.16132T=DSM 105258T).

Paracoccus liaowanqingii sp. nov., isolated from Tibetan antelope (Pantholops hodgsonii).

Two strains, designated 2251T and 3058, that were aerobic, Gram-stain-negative, non-motile, coccoid or short rod-shaped bacilli, have recently been isolated from Tibetan antelopes on the Qinghai-Tibet Plateau. The results of phylogenetic analyses of 16S rRNA gene sequences indicated that strains 2251T and 3058 represent a new species within the genus Paracoccus and are most similar to 'Paracoccus gahaiensis' CUG00006T (98.9 and 99.3 %), Paracoccus nototheniae I-41R45T (98.3 and 98.7 %) and Paracoccus hibiscisoli THG-T2.31T (97.6 and 97.8 %). Results of genomic sequence-based phylogenomic analysis agreed with those from 16S rRNA gene sequence analysis. Optimal growth was achieved at pH 7.0-7.5 and 28 °C with marine medium. Cells contained C18 : 1 ω7c as the major cellular fatty acid and ubiquinone-10 as the predominant menaquinone. The polar lipids comprised phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phospholipid, glycolipid and an unidentified lipid. The cell-wall peptidoglycan amino acids were meso-2,6-diaminopimelic acid, alanine and glutamic acid; the major cell-wall sugar was galactose. The G+C content of strain 2251T was 66.5 mol%. Both strains (2251T and 3058) had DNA-DNA relatedness values less than 50 % with all available genomes of the genus Paracoccus in the ncbi database. Differential genotypic inferences, together with phenotypic and biochemical characteristics, demonstrated that strains 2251T and 3058 should be classified as a novel species of the genus Paracoccus, for which the name Paracoccus liaowanqingii sp. nov. is suggested. The type strain is 2251T (=CGMCC 1.16490T=DSM 106269T).

Description of Ornithinibacillus gellani sp. nov., a halophilic bacterium isolated from lake sediment, and emended description of the genus Ornithinibacillus.

A Gram-stain-positive, strictly aerobic, motile and rod-shaped bacterium, designated strain LJ137T, was isolated from the sediment of Taihu Lake in China. A polyphasic approach was used to investigate its taxonomic position. Strain LJ137T grew optimally at pH 7.5, at 37 °C and with 2.5 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain LJ137T was most closely related to the genera Ornithinibacillus and Oceanobacillus. The closest phylogenetic neighbours were Ornithinibacillus halophilus KCTC 13822T, Ornithinibacillus salinisoli LCB256T and Oceanobacillus limi KCTC 13823T, with 95.2, 96.5 and 95.6 % 16S rRNA gene sequence similarity, respectively. The peptidoglycan amino acid type was A4α (l-Lys-d-Asp). The major respiratory quinone was menaquinone-7 (MK-7). The polar lipids of strain LJ137T contained diphosphatidylglycerol, phosphatidylglycerol, three unidentified phospholipids, two aminophospholipids and one unidentified lipid. The G+C content of the genomic DNA was 40.4 mol%. The dominant cellular fatty acids were anteiso-C15 : 0, anteiso-C17 : 0 and iso-C15 : 0. Based on the phenotypic, chemotaxonomic, phylogenetic and genome sequence characteristics of this strain, a novel species, Ornithinibacillus gellani sp. nov., is proposed. The type strain is LJ137T (=CGMCC 1.13678T=NBRC 113552T). An emended description of the genus Ornithinibacillus is presented.

Reclassification of Arthrobacter endophyticus (Wang et al. 2015) as Glutamicibacter endophyticus comb. nov.

The species Arthrobacterendophyticus is phylogenetically placed within the Glutamicibacter clade and shares 97.3-98.4 % 16S rRNA gene sequence similarities with the species of this genus. The quinone system with the major menaquinone MK-9 and the peptidoglycan amino acids alanine, glutamic acid and lysine are consistent with the characteristics of the members of the genus Glutamicibacter but the polar lipid profile with phosphatidylinositol distinguishes A. endophyticus from species of the genus Glutamicibacter. Re-analysis of both peptidoglycan structure and polar lipid profile revealed peptidoglycan type l-Lys-l-Ala-l-Glu (A11.35) and a polar lipid profile lacking phosphatidylinositol. These traits are consistent with those of representatives of the genus Glutamicibacter and distinguish A. endophyticus from members of the genus Arthrobacter sensu stricto. Due to its phylogenetic position and congruence with the key characteristics of members of the genus Glutamicibacter we here propose the reclassification of Arthrobacter endophyticus as a species of the genus Glutamicibacter, Glutamicibacter endophyticus comb. nov. (EGI 6500322T=DSM 28750T=KCTC 29490T=JCM 30091T).

Deinococcus terrigena sp. nov., a novel member of the family Deinococcaceae.

A bacterial strain, S13-1-2-1T, was isolated from a soil sample collected in Gyeongsangnam-do province, South Korea. Cells were observed to be Gram-stain negative, short rod-shaped and colonies to be pale pink in colour. Analysis of 16S rRNA gene sequences identified this strain as a member of the genus Deinococcus in the family Deinococcaceae, with high levels of sequence similarity with Deinococcus ficus CC-FR2-10T (97.9%) and Deinococcus enclensis NIO-1023T (95.4%). Growth of strain S13-1-2-1T was observed at 10-42°C, pH 6-8, and in the presence of 0-1.0% NaCl. The isolate was found to exhibit resistance to gamma radiation (D10 10.1 KGy) and UV-light (D10 612J/m2). The major peptidoglycan amino acids were identified as D-glutamic acid, glycine, alanine and L-ornithine. The predominant respiratory quinone of the strain was identified as menaquinone-8, the major fatty acids were found to be C16:1ω7c (31.4%), C16:0 (18.4%), and C17:1ω8c (17.4%) and the major polar lipids were observed to be an unidentified phosphoglycolipid and an unidentified glycolipid. The genomic DNA G + C content of the strain was determined to be 69.2mol%. DNA-DNA hybridization with D. ficus showed a relatedness value of 31.5 ± 4.2%. The DNA-DNA hybridization result and the differentiating phenotypic properties clearly indicate that strain S13-1-2-1T represents a novel species in the genus Deinococcus, for which the name Deinococcus terrigena sp. nov. is proposed. The type strain is S13-1-2-1T (= KCTC 33939T = JCM 32248T).

Deinococcus koreensis sp. nov., a gamma radiation-resistant bacterium isolated from river water.

A gamma radiation-resistant, Gram-stain-negative, rod-shaped bacterial strain, designated SJW1-2T, was isolated from freshwater samples collected from the Seomjin River, Republic of Korea. The 16S rRNA gene sequence analyses showed that strain SJW1-2T was most closely related to Deinococcus metalli 1PNM-19T (94.3 % sequence similarity) and formed a robust phylogenetic clade with other species of the genus Deinococcus. The optimum growth pH and temperature for the isolate were pH 7.0-7.5 and 25 °C, respectively. Strain SJW1-2T exhibited high resistance to gamma radiation. The predominant respiratory quinone was MK-8. The polar lipid profile consisted of different unidentified glycolipids, two unidentified lipids, two unidentified phospholipids and an unidentified phosphoglycolipid. The major peptidoglycan amino acids were alanine, d-glutamic acid, glycine and l-ornithine. The predominant fatty acids (>10 %) were summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) (25.2 %) and C16 : 0 (21.2 %), and the DNA G+C content was 69.5 mol%. On the basis of phenotypic, genotypic and phylogenetic analyses, strain SJW1-2T (=KACC 19332T=NBRC 112908T) represents a novel species of the genus Deinococcus, for which the name Deinococcus koreensis sp. nov. is proposed.

A novel pigmented and heavy metal biosorptive bacterium, Leucobacter epilobiisoli sp. nov., isolated from rhizosphere soil of Epilobium hirsutum L.

A novel yellow pigmented, Gram-positive, aerobic and heavy metal biosorptive bacterium designated SYP-B2667T was isolated from rhizosphere soil of Epilobium hirsutum L. in Tongren, Guizhou province, China. Based on 16S rRNA gene sequence analyses, it was shown that strain SYP-B2667T represents a novel species in the genus Leucobacter, with Leucobacter chromiireducens subsp. solipictus JCM 15573T as a close phylogenetic neighbour (sequence similarity of 98.2%). Chemotaxonomic characteristics also supported the affiliation to the genus Leucobacter. Strain SYP-B2667T was determined to have a DNA G+C content of 66.6mol%; 2,4-diaminobutyric acid in the cell wall peptidoglycan amino acids; MK-11 as predominant menaquinone; an abundance of anteiso-C15:0 and anteiso-C17:0 fatty acids; and polar lipids including diphosphatidylglycerol, phosphatidylglycerol, glycolipids and unidentified phospholipids. The DNA-DNA hybridization value between strain SYP-B2667T and L. chromiireducens subsp. solipictus JCM 15573T was 19.7 ± 2.8%. Based on these phylogenetic and phenotypic results, it can be concluded that strain SYP-B2667T represents a novel species, for which the name Leucobacter epilobiisoli sp. nov. is proposed. The type strain is SYP-B2667T (=DSM 105145T=CPCC 204976T). This strain can tolerate and adsorb five heavy metals and so may have potential to facilitate heavy metal removal and bioremediation.

Ornithinibacillus salinisoli sp. nov., a moderately halophilic bacterium isolated from a saline-alkali soil.

A taxonomic study was performed on strain LCB256T, which was isolated from a saline-alkali soil sample taken from northwestern China. Cells of strain LCB256T were Gram-stain-positive, aerobic, rod-shaped and grew at 3-17 % (w/v) NaCl (optimum 10-15 %), 10-52 °C (optimum 25-30 °C) and pH 7.0-9.0 (optimum 8.0). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain LCB256T was most closely related to the two genera of Ornithinibacillus and Oceanobacillus, showing highest sequence similarity to Oceanobacillus limi KCTC 13823T (97.8 %) and Ornithinibacillus bavariensis WSBC 24001T (97.2 %). The peptidoglycan amino acid type was found to be A4β and the major respiratory quinone was determined to be MK-7. The polar lipid profile of strain LCB256T contained diphosphatidylglycerol, phosphatidylglycerol, one unidentified phospholipid and two unidentified aminolipids. The dominant cellular fatty acids were anteiso-C15 : 0 and iso-C15 : 0. The G+C content of genomic DNA was 39.3 mol%. DNA-DNA relatedness values between strain LCB256T and Ornithinibacillus halophilus KCTC 13822T and Oceanobacillus limi KCTC 13823T were 46.2 and 34.8 %, respectively. Based on this polyphasic taxonomic study, a novel species of the genus Ornithinibacillus, Ornithinibacillussalinisoli sp. nov. is proposed. The type strain is LCB256T (=CGMCC 1.15809T=KCTC 33862T).

Leucobacter weissii sp. nov., an isolate from activated sludge once described as first representative of the peptidoglycan variation B2δ, and emended description of the genus Leucobacter.

Strain S27T is a Gram-stain-positive, regular rod-shaped, non-motile, non-spore-forming, yellow pigmented actinobacterium which was isolated from an aerated laboratory scale fermenter fed with wastes of a yeast factory. The strain was classified as Microbacterium sp. after the analysis of its peptidoglycan revealed a novel B-type structure established as variation B2δ by Hensel in 1984. As the combination of the peptidoglycan amino acids 2,4-diaminobutyric acid (Dab), threonine (Thr), glycine (Gly), alanine (Ala) and glutamic acid (Glu) is in disagreement with the current genus definition of Microbacterium but is typical of several Leucobacter species, the taxonomic status of strain S27T was re-examined by a polyphasic study. Comparative analyses of 16S rRNA gene sequences and the occurrence of l-Dab, d-Ala, l-Ala, Gly, l-Thr, d-Glu and lower amounts of l-Glu in the peptidoglycan in combination with the predominating menaquinones MK-11, MK-10 and MK-9, phosphatidylglycerol, and one unknown glycolipid as the major polar lipids (and trace amounts of diphosphatidylglycerol and an unknown phospholipid), a profile with anteiso-C15 : 0, iso-C15 : 0, iso-C16 : 0, anteiso-C17 : 0 and iso-C17 : 0 as major fatty acids and the G+C value of 70.1 mol% confirmed the affiliation to the genus Leucobacter and revealed that S27T (=DSM 20621T =CCM 8762T) is the type strain of a new species for which the name Leucobacter weissii sp. nov. is proposed. The availability of new data allows for an emended description of the genus Leucobacter.

Deinococcus hibisci sp. nov., isolated from rhizosphere of Hibiscus syriacus L. (mugunghwa flower)

A Gram-stain-positive, pink-pigmented, coccus-shaped, strictly aerobic, non-motile bacterium, strain THG-AG1.5T, was isolated from rhizosphere of Hibiscus syriacus L. (Mugunghwa flower) located in Kyung Hee University, Yongin, Gyeonggi, Republic of Korea. The isolated strain grew optimally at 25-30 °C, at pH 6.0-7.5 and in the presence of additional 0-1.5 % (w/v) NaCl. Strain THG-AG1.5T exhibited tolerance to UV radiation (>1500 J m-2) and to gamma radiation (>12 kGy). Based on 16S rRNA gene sequence comparisons, strain THG-AG1.5T was closely related to Deinococcus daejeonensis MJ27T (98.03 %), Deinococcus radiotolerans C1T (97.61 %) and Deinococcus grandis DSM 3963T (97.32 %). The genomic DNA G+C content of strain THG-AG1.5T was 74.8 mol%. The DNA-DNA hybridization values between strain THG-AG1.5T and its closest phylogenetically neighbours were below 63.0 %. The peptidoglycan amino acids were alanine, valine, glutamic acid, glycine, ornithine, lysine and aspartic acid. Strain THG-AG1.5T contained ribose, mannose and glucose as whole-cell-wall sugars and menaquinone-8 (MK-8) as the only isoprenoid quinone. The major component in the polyamine pattern was spermidine. The major polar lipids of strain THG-AG1.5T were a phosphoglycolipid, six unidentified glycolipids and an unidentified aminophospholipid. The major fatty acids were identified as iso-C15 : 0, C15 : 1ω6c, C16 : 0, iso-C17 : 0, C17 : 0, C18 : 0 and summed feature 3. On the basis of our polyphasic taxonomy study, strain THG-AG1.5T represents a novel species within the genus Deinococcus, for which the name Deinococcushibisci sp. nov. is proposed. The type strain is THG-AG1.5T (=KACC 18850T=CCTCC AB 2016078T).

Ornithinibacillus composti sp. nov., isolated from sludge compost and emended description of the genus Ornithinibacillus.

A Gram-stain positive, aerobic, motile, endospore-forming and rod-shaped bacterium, designated GSS05(T), was isolated from a sludge compost sample and was characterized by means of a polyphasic taxonomic approach. Growth was observed to occur with 0-3% (w/v) NaCl (optimum 1%), at pH 5.5-10 (optimum pH 7.5) and at 15-50°C (optimum 37°C). According to the results of a phylogenetic analysis, strain GSS05(T) was found to belong to the genus Ornithinibacillus and to be related most closely to the type strains of Ornithinibacillus halotolerans and Ornithinibacillus contaminans (96.5 and 95.1% 16S rRNA gene sequence similarity, respectively). The peptidoglycan amino acid type was determined to be A4β. The major respiratory quinone was identified as menaquinone-7 (MK-7). The polar lipid profile of strain GSS05(T) was found to contain a predominance of diphosphatidylglycerol, moderate amounts of phosphatidylglycerol and minor amounts of two unknown phospholipids and two unknown lipids. The G+C content of genomic DNA was determined to be 42.1mol%. The dominant cellular fatty acids were identified as iso-C15:0 and anteiso-C15:0. The phenotypic, chemotaxonomic, phylogenetic and genotypic data indicated that strain GSS05(T) represents a novel species of the genus Ornithinibacillus, for which the name Ornithinibacillus composti sp. nov. is proposed. The type strain is GSS05(T) (=CCTCC AB 2013261(T)=KCTC 33192(T)).

Corynebacterium atrinae sp. nov., isolated from the gastrointestinal tract of a pen shell, Atrina pectinata.

A novel Gram-stain-positive, non-motile, facultatively anaerobic and rod-shaped bacterium, strain PSPT56(T), was isolated from the gastrointestinal tract of a pen shell (Atrina pectinata). Optimal growth of strain PSPT56(T) was ascertained to occur at 30 °C, pH 8.0 and in the presence of 1-2 % (w/v) NaCl. The strain was catalase-positive and oxidase-negative. The major cellular fatty acids were C18 : 1ω9c, C16 : 0, C17 : 1ω8c and C17 : 0. Tuberculostearic acid was not present. The major cell-wall sugars were ribose, galactose, glucose and arabinose. Peptidoglycan amino acids were meso-diaminopimelic acid, alanine and glutamic acid. The predominant isoprenoid quinone was MK-8(H2). Strain PSPT56(T) contained phosphatidylglycerol, diphosphatidylglycerol, an unidentified phospholipid, two unidentified lipids and two unidentified amino-lipids. Mycolic acids were detected as constitutive components of the cell wall. A phylogenetic analysis based on 16S rRNA gene sequence similarity showed that strain PSPT56(T) was most closely related to Corynebacterium testudinoris M935/96/4(T) and Corynebacterium felinum M714/95/5(T) with 98.69 % and 97.01 % similarity, respectively. DNA-DNA hybridization experiments indicated less than 29.9 % relatedness to the phylogenetically closest species. The G+C content of genomic DNA was 67.6 mol%. The phenotypic, phylogenetic and genotypic analyses indicated that strain PSPT56(T) represents a novel species within the genus Corynebacterium, for which the name Corynebacterium atrinae is proposed. The type strain is PSPT56(T) ( = KACC 17525(T) = JCM 19266(T)).

Ornithinibacillus halotolerans sp. nov., isolated from a saline soil

A Gram-staining-positive, aerobic, motile, endospore-forming, rod-shaped bacterium, designated GD04T, was isolated from a saline soil sample taken in southern China and was characterized by means of a polyphasic approach. Growth occurred with 0.5-12% (w/v) NaCl (optimum 1-2%) and at pH 7.0-9.5 (optimum pH 8.0) and 10-45 °C (optimum 30 °C). According to the results of a phylogenetic analysis, strain GD04T belonged to the genus Ornithinibacillus, and was related most closely to type strains of the species Ornithinibacillus bavariensis and Ornithinibacillus contaminans (96.5 and 96.5% 16S rRNA gene sequence similarities, respectively). The peptidoglycan amino acid type was A4β, containing L-ornithine and d-aspartic acid. The major respiratory quinone was menaquinone-7 (MK-7). The polar lipid profile of strain GD04T contained predominantly diphosphatidylglycerol with moderate amounts of phosphatidylglycerol, phosphatidylinositol, an unknown phospholipid and an unknown lipid, and a minor amount of another unknown lipid. The G+C content of genomic DNA was 39.3 mol%. The dominant cellular fatty acids were iso-C16:0, iso-C15:0 and anteiso-C15:0. The phenotypic, chemotaxonomic, phylogenetic and genotypic data indicated that strain GD04T represents a novel species of the genus Ornithinibacillus, for which the name Ornithinibacillus halotolerans sp. nov. is proposed. The type strain is GD04T (=KCTC 33116T=CGMCC 1.12408T).

Amino acid biogeochemistry and bacterial contribution to sediment organic matter along the western margin of the Bay of Bengal

Six sediment cores collected from various water depths and sampling locations along the western margin of the Bay of Bengal (BOB) were investigated for the total hydrolysable amino acids (THAA) and d-amino acids (d-AA) to understand their distribution, digenetic alteration and bacterial contribution to organic matter (OM). Irrespective of their location, THAA concentrations and yields generally decreased and mol% glycine increased with increasing water depth indicating that OM was degraded during its transit through the water column. Amino acid based degradation index (DI) indicated that OM of the surface sediments of shallow stations, BOB-1 to BOB-3 was relatively fresher than that of deeper stations, BOB-4, BOB-5 and BOB-6. The concentrations and mol% of the d-AA varied from 0.04 to 0.76µmolgdw−1 and 0.3 to 8.5mol%, respectively. Contribution of bacterial peptidoglycan amino acids to THAA (% THAApep/THAA) ranged between 4.0% and 55.0%. Both % THAApep/THAA and mol% d-AAs were significantly (p<0.01) higher in the surface sediments and decreased with sediment core depth. Based on the d-AA yields, bacterial OM accounted for 1.5–15.6% of TOC, and 3.7–50.0% of TN of the sediments of BOB.

Kallotenue papyrolyticum gen. nov., sp. nov., a cellulolytic and filamentous thermophile that represents a novel lineage (Kallotenuales ord. nov., Kallotenuaceae fam. nov.) within the class Chloroflexia

Several closely related, thermophilic and cellulolytic bacterial strains, designated JKG1(T), JKG2, JKG3, JKG4 and JKG5, were isolated from a cellulolytic enrichment (corn stover) incubated in the water column of Great Boiling Spring, NV. Strain JKG1(T) had cells of diameter 0.7-0.9 µm and length ~2.0 µm that formed non-branched, multicellular filaments reaching >300 µm. Spores were not formed and dense liquid cultures were red. The temperature range for growth was 45-65 °C, with an optimum of 55 °C. The pH range for growth was pH 5.6-9.0, with an optimum of pH 7.5. JKG1(T) grew as an aerobic heterotroph, utilizing glucose, sucrose, xylose, arabinose, cellobiose, CM-cellulose, filter paper, microcrystalline cellulose, xylan, starch, Casamino acids, tryptone, peptone, yeast extract, acetate, citrate, lactate, pyruvate and glycerol as sole carbon sources, and was not observed to photosynthesize. The cells stained Gram-negative. Phylogenetic analysis using 16S rRNA gene sequences placed the new isolates in the class Chloroflexia, but distant from other cultivated members, with the highest sequence identity of 82.5 % to Roseiflexus castenholzii. The major quinone was menaquinone-9; no ubiquinones were detected. The major cellular fatty acids (>5 %) were C18 : 0, anteiso-C17 : 0, iso-C18 : 0, iso-C17 : 0, C16 : 0, iso-C16 : 0 and C17 : 0. The peptidoglycan amino acids were alanine, ornithine, glutamic acid, serine and asparagine. Whole-cell sugars included mannose, rhamnose, glucose, galactose, ribose, arabinose and xylose. Morphological, phylogenetic and chemotaxonomic results suggest that JKG1(T) is representative of a new lineage within the class Chloroflexia, which we propose to designate Kallotenue papyrolyticum gen. nov., sp. nov., Kallotenuaceae fam. nov., Kallotenuales ord. nov. The type strain of Kallotenue papyrolyticum gen. nov., sp. nov. is JKG1(T) ( = DSM 26889(T) = JCM 19132(T)).

Transcriptome Analysis of Responses to Rhodomyrtone in Methicillin-Resistant Staphylococcus aureus

Rhodomyrtone, purified from Rhodomyrtus tomentosa (Aiton) Hassk, exhibits a high degree of potency against methicillin-resistant Staphylococcus aureus (MRSA). We recently demonstrated that exposure of MRSA to a subinhibitory concentration (0.174 µg/ml) of rhodomyrtone resulted in the alteration of expression of several functional classes of bacterial proteins. To provide further insight into the antibacterial mode of action of this compound, we determined the impact of exposure to rhodomyrtone on the gene transcriptional profile of MRSA using microarray analysis. Exposure of MRSA to subinhibitory concentrations (0.5MIC; 0.5 µg/ml) of rhodomyrtone revealed significant modulation of gene expression, with induction of 64 genes and repression of 35 genes. Prominent changes in response to exposure to rhodomyrtone involved genes encoding proteins essential to metabolic pathways and processes such as amino acid metabolism, membrane function, ATP-binding cassette (ABC) transportation and lipoprotein and nucleotide metabolism. Genes involved in the synthesis of the aspartate family of amino acids, in particular proteins encoded by the dap operon were prominent. The diaminopimelate (DAP) biosynthetic pathway is the precursor of lysine synthesis and is essential for peptidoglycan biosynthesis. However, phenotypic analysis of the peptidoglycan amino acid content of rhodomyrtone-treated MRSA did not differ significantly from that extracted from control cells. Genes involved in the biosynthesis of amino acids and peptidoglycan, and a high affinity ATP-driven K (+) transport system, were investigated by quantitative reverse transcription-PCR (qRT-PCR) using EMRSA-16 1, 4, or 18 h after exposure to rhodomyrtone and in general the data concurred with that obtained by microarray, highlighting the relevance of the DAP biosynthetic pathway to the mode of action of rhodomyrtone.