Amycolatopsis Camponoti Sp. Nov., New Tetracenomycin-Producing Actinomycete Isolated from Carpenter Ant Camponotus Vagus

An actinobacterial strain A23T, isolated from adult ant Camponotus vagus collected in Ryazan region (Russia) and established as tetracenomycin X producer, was subjected to a polyphasic taxonomic study. Morphological characteristics of this strain included well-branched substrate mycelium and aerial hyphae fragmented into rod-shaped elements. Phylogenetic analyses based on 16S rRNA gene and genome sequences showed that strain A23T was most closely related to Amycolatopsis pretoriensis DSM 44654T (99.9%). Average nucleotide identity and digital DNA–DNA hybridization values between the genome sequences of isolate A23T and its closest relative, Amycolatopsis pretoriensis DSM 44654T, were 39.5% and 88.6%, which were below the 70% and 95-96% cut-off point recommended for bacterial species demarcation, respectively. The genome size of the isolate A23T is 10,560,374 bp with a DNA G+C content of 71.2 mol%. The whole-organism hydrolysates contain arabinose and galactose as main diagnostic sugars as well as ribose and rhamnose. It contained MK-9(H4) as the predominant menaquinone and iso-C16:0, iso-C15:0, anteiso-C17:0 and C16:0 as the major cellular fatty acids. Based on the phenotypic, genomic and phylogenetic data, isolate A23T represents a novel species of the genus Amycolatopsis, for which the name Amycolatopsis camponoti sp. nov. is proposed, and the type strain is A23T (=DSM 111725T =VKM 2882T).

Caldicellulosiruptor diazotrophicus sp. nov., a thermophilic, nitrogen-fixing fermentative bacterium isolated from a terrestrial hot spring in Japan

A novel nitrogen-fixing fermentative bacterium, designated as YA01T, was isolated from Nakabusa hot springs in Japan. The short-rod cells of strain YA01T were Gram-positive and non-sporulating. Phylogenetic trees of the 16S rRNA gene sequence and concatenated sequences of 40 single-copy ribosomal genes revealed that strain YA01T belonged to the genus Caldicellulosiruptor and was closely related to Caldicellulosiruptor hydrothermalis 108T, Caldicellulosiruptor bescii DSM 6725T and Caldicellulosiruptor kronotskyensis 2002T. The 16S rRNA gene sequence of strain YA01T shares less than 98.1 % identity to the known Caldicellulosiruptor species. The G+C content of the genomic DNA was 34.8 mol%. Strain YA01T shares low genome-wide average nucleotide identity (90.31–91.10 %), average amino acid identity (91.45–92.10 %) and <70 % digital DNA–DNA hybridization value (41.8–44.2 %) with the three related species of the genus Caldicellulosiruptor . Strain YA01T grew at 50–78 °C (optimum, 70 °C) and at pH 5.0–9.5 (optimum, pH 6.5). Strain YA01T mainly produced acetate by consuming d(+)-glucose as a carbon source. The main cellular fatty acids were iso-C17 : 0 (35.7 %), C16 : 0 (33.3 %), DMA16 : 0 (6.6 %) and iso-C15 : 0 (5.9 %). Based on its distinct phylogenetic position, biochemical and physiological characteristics, and the major cellular fatty acids, strain YA01T is considered to represent a novel species of the genus Caldicellulosiruptor for which the name Caldicellulosiruptor diazotrophicus sp. nov. is proposed (type strain YA01T=DSM 112098T=JCM 34253T).

Maribrevibacterium harenarium gen. nov., sp. nov., represented by a marine strain of the family Oceanospirillaceae

A Gram-stain-negative, non-motile, facultatively anaerobic, short rod-shaped bacterium, designated HB171799T, was isolated from seacoast sandy soil collected at Qishui Bay, Hainan, PR China. The chemotaxonomic analysis revealed that the respiratory quinones were Q-8 and Q-7, and the major cellular fatty acids were summed feature 8 (comprising C18 : 1 ω7c and/or C18 : 1 ω6c), C16 : 0 and C18 : 0. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unidentified phospholipid and an unidentified lipid. The size of the draft genome was 3.68 Mb with a DNA G+C content of 48.0 mol%. Results of phylogenetic analyses based on 16S rRNA gene and genome sequences showed that the novel isolate belonged to the family Oceanospirillaceae and formed a distinct subcluster at the base of the radiation of the genus Marinomonas . The highest sequence similarity (96.0 %) of the novel isolate was found to the type strains of Marinomonas fungiae JCM 18476T and Marinomonas ostreistagni DSM23425T. The whole genome-based phylogeny and differences in cellular fatty acids and polar lipids readily distinguished strain HB171799T from all the closely related validly published type strains. Strain HB171799T is therefore suggested to represent a novel species of a new genus in the family Oceanospirillaceae , for which the name Maribrevibacterium harenarium gen. nov., sp. nov. is proposed. The type strain is HB171799T (=CGMCC 1.16727T=JCM 33332T).

Microvirga Amygdalina sp. nov., and Microvirga Alba sp. nov., Two New Species Isolated from Soil in South Korea

Two novel Gram-stain-negative, aerobic, rod-shaped, circular, convex, light-pink and white-coloured bacterial strains BT291T and BT350T were isolated from soil collected in Uijeongbu city (37° 44′ 55″ N, 127° 2′ 20″ E) and Jeju island (33° 22′ 48″ N, 126° 31′ 48″ E), respectively, South Korea. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strains BT291T and BT350T belong to a distinct lineage within the genus Microvirga (family Methylobacteriaceae, order Rhizobiales, class Alpha Proteobacteria, phylum Proteobacteria, kingdom Bacteria). The 16S rRNA gene sequence similarity between the two strains BT291T and BT350T was 97.4 %. The two strains were found to have the same quinone system, with Q-10 as the major respiratory quinone. The major polar lipids of strains BT291T and BT350T were phosphatidylethanolamine (PE), diphosphatydilglycerol (DPG), phosphatidylcholine (PC) and phosphatidylglycerol (PG). The major cellular fatty acids of strain BT291T were C18:1 ω7c (58.2 %) and cyclo-C19:0 ω8c (25.7 %). The major cellular fatty acids of strain BT350T were C18:1 ω7c (38.5 %) and cyclo-C19:0 ω8c (27.7 %). Based on the polyphasic analysis (phylogenetic, chemotaxonomic and biochemical), strains BT291T and BT350T can be suggested as two novel bacterial species within the genus Microvirga and the proposed names are Microvirga amygdalina and Microvirga alba, respectively. The type strain of Microvirga amygdalina is BT291T (= KCTC 72368T = NBRC 114845T) and the type strain of Microvirga alba is BT350T (= KCTC 72385T = NBRC 114848T).

Muricauda Chongwuensis Sp. Nov., Isolated From Coastal Seawater of China

In the course of screening for bacterial predator, a Gram-negative, non-flagellated, gliding, long rod-shaped and yellow-pigmented bacterium, designated strain HICWT, was isolated from coastal seawater of China. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain HICWT represented a member of the genus Muricauda and showed the highest sequence similarity to M. aquimarina JCM11811T (98.8%) and M. ruestringensis DSM13258T (98.1%). NaCl was required for growth. Optimum growth occurred at 25–30 oC, 2.0–3.0% (w/v) NaCl with pH 7.0. Strain HICWT showed some similar characteristics to the nonobligate bactertal predators, the cells can attach the prey cells. Strain HICWT contained MK-6 as the predominant respiratory quinone and had iso-C15:0, iso-C15:1 G and iso-C17:0 3-OH as the major cellular fatty acids. The polar lipids contained phosphatidylethanolamine (PE), three unknown phospholipids (PL1–PL3), one unknown aminolipids (AL) and three unknown polar lipids (L1–L3). The genome size of strain HICWT was approximately 3.8 Mbp, with a G+C content of 41.4%. On the basis of the polyphasic evidence, strain HICWT is proposed as representing a new species of the genus Muricauda, for which the name Muricauda chongwuensis sp. nov. is proposed. The type strain is HICWT (=JCM 33643T=MCCC 1K03769T).

Unicellular versus Filamentous: The Glacial Alga Ancylonema alaskana comb. et stat. nov. and Its Ecophysiological Relatedness to Ancylonema nordenskioeldii (Zygnematophyceae, Streptophyta)

Melting polar and alpine ice surfaces frequently exhibit blooms of dark pigmented algae. These microbial extremophiles significantly reduce the surface albedo of glaciers, thus accelerating melt rates. However, the ecology, physiology and taxonomy of cryoflora are not yet fully understood. Here, a Swiss and an Austrian glacier dominated either by filamentous Ancylonema nordenskioeldii or unicellular Mesotaenium berggrenii var. alaskanum, were sampled. Molecular analysis showed that both species are closely related, sharing identical chloroplast morphologies (parietal-lobed for Ancylonema vs. axial plate-like for Mesotaenium sensu stricto), thus the unicellular species was renamed Ancylonema alaskana. Moreover, an ecophysiological comparison of the two species was performed: pulse–amplitude modulated (PAM) fluorometry confirmed that they have a high tolerance to elevated solar irradiation, the physiological light preferences reflected the conditions in the original habitat; nonetheless, A. nordenskioeldii was adapted to higher irradiances while the photosystems of A. alaskana were able to use efficiently low irradiances. Additionally, the main vacuolar polyphenol, which effectively shields the photosystems, was identical in both species. Also, about half of the cellular fatty acids were polyunsaturated, and the lipidome profiles dominated by triacylglycerols were very similar. The results indicate that A. alaskana is physiologically very similar and closely related but genetically distinct to A. nordenskioeldii.

Devosia Sediminis sp. nov., Isolated from Fubterranean Sediment.

A novel Gram- negative, cream-colored, rod-shaped, aerobic, non-motile bacterium, designated MSA67T, was isolated from a subterranean sediment sample of the Mohe Basin in Northeast China. Strain MSA67T was detected to grow at 4–40°C (optimum, 28–30°C), pH 5.0–10.0 (optimum, pH 7.0) and in 0.0–8.0 % (w/v) NaCl (optimum, 2.0–3.0 %). Phylogenetic analysis based on 16S rRNA gene sequence revealed that strain MSA67T was a member of the genus Devosia, with the highest similarity with D. riboflavina IFO13584T (98.0 %) and D. chinhatensis IPL18T (97.0 %). The major cellular fatty acids are C16:0, C18:1ω7c 11-methyl and C18:1ω6c and/or C18:1ω7c. The major polar lipids are diphosphatidylglycerol, phosphatidylglycerol, glycolipids and three unidentified phospholipids. The major respiratory quinone is ubiquinone 10 (Q-10). The genomic size of strain MSA67T is 4.1 MB and DNA G + C content is 63.6 %. Based on genotypic, phenotypic and phylogenetic results, strain MSA67T is concluded to represent a novel species of the genus Devosia, for which the name Devosia sediminis sp. nov. is proposed. The type strain is MSA67T (= CGMCC 1.18467T = KCTC 82192T).

Leuconostoc falkenbergense sp. nov., isolated from a lactic culture, fermentating string beans and traditional yogurt

In the present study, the taxonomic positions of five strains (C, 17-2, LMG 10779T, LMG 18969 and LMG 11483) of Leuconostoc pseudomesenteroides were re-evaluated by a polyphasic approach, including the analyses of 16S rRNA, pheS and rpoA gene sequences, cellular fatty acids, average nucleotide and amino acid identities (ANI and AAI), digital DNA–DNA hybridization (dDDH), and phenotypic features. Based on rpoA sequence analysis, the five strains and L. pseudomesenteroides LMG 11482T were divided into two groups: strains C, LMG 10779T and LMG 18969; strains 17-2, LMG 11483 and LMG 11482T. Each of the two groups had almost identical rpoA sequences. The rpoA sequence similarity between strain LMG 10779T and L. pseudomesenteroides LMG 11482T was 95.6 %. Strains LMG 11483 and 17-2 had 98.1 and 97.2 % ANI values, 83.5 and 73.2 % dDDH values, and a 97.0 % AAI value with L. pseudomesenteroides LMG 11482T, greater than the threshold for species demarcation, indicating that strains LMG 11483 and 17-2 belong to L. pseudomesenteroides . Strains LMG 18969 and C shared 97.1 and 98.2 % ANI values, 73.4 and 83.2 % dDDH values, and 96.9 and 96.6 % AAI values with strain LMG 10779T, greater than the threshold for species demarcation, indicating that strains LMG 10779T, LMG 18969 and C represent the same species. The ANI, dDDH and AAI values between strain LMG 10779T and the type strains of phylogenetically related species were 75.2–92.5, 20.0–48.2 and 75.3–93.9 %, respectively, below the thresholds for species demarcation, indicating that strain LMG 10779T represents a novel species within the genus Leuconostoc . On the basis of the results presented here, (i) strains 17-2 and LMG 11483 belong to L. pseudomesenteroides , and (ii) strains LMG 10779T, LMG 18969 and C are considered to represent a novel species within the genus Leuconostoc , for which the name Leuconostoc falkenbergense sp. nov. is proposed with the type strain LMG 10779T (=CCUG 27119T).

Pseudidiomarina piscicola sp. nov., isolated from cultured European seabass, Dicenthrarchus labrax

Strain CECT 9734 T, a Gram-negative, aerobic, chemoorganotrophic bacterium, motile by polar flagella, was isolated from cultured European seabass, Dicenthrarchus labrax, in Spain. It grows from 5 to 42 ºC, 6–9 pH and 1–12% total salinity. Major cellular fatty acids are C15:0 iso, summed feature 9 (C17:1 iso w9c/C16:0 10-methyl) and C17:0 iso. The genome size is 2.5 Mbp and G + C content is 49.5 mol%. Comparative analysis of the 16S rRNA gene sequence shows that the strain is a member of Pseudidiomarina, with highest similarities with Pseudidiomarina halophila (97.0%) and Pseudidiomarina salinarum (96.9%). Phylogenomic tree based on UBCG program shows P. halophila as its closest relative. ANI and in-silico DDH with other Pseudidiomarina spp. are lower than 87 and 20%, respectively, suggesting that strain CECT 9734 T represents a new species, for which we propose the name Pseudidiomarina piscicola sp. nov. and CECT 9734 T (= LUBLD50 7aT = LMG 31044 T) as type strain.

A systematic review of the genera Geobacillus and Parageobacillus: their evolution, current taxonomic status and major applications

The genus Geobacillus , belonging to the phylum Firmicutes, is one of the most important genera and comprises thermophilic bacteria. The genus Geobacillus was erected with the taxonomic reclassification of various Bacillus species. Taxonomic studies of Geobacillus remain in progress. However, there is no comprehensive review of the characteristic features, taxonomic status and study of various applications of this interesting genus. The main aim of this review is to give a comprehensive account of the genus Geobacillus . At present the genus acomprises 25 taxa, 14 validly published (with correct name), nine validly published (with synonyms) and two not validly published species. We describe only validly published species of the genera Geobacillus and Parageobacillus . Vegetative cells of Geobacillus species are Gram-strain-positive or -variable, rod-shaped, motile, endospore-forming, aerobic or facultatively anaerobic, obligately thermophilic and chemo-organotrophic. Growth occurs in the pH range 6.08.5 and a temperature of 37–75 °C. The major cellular fatty acids are iso-C15:o, iso-C16:0 and iso-C17:o. The main menaquinone type is MK-7. The G­+C content of the DNA ranges between 48.2 and 58 mol%. The genus Geobacillus is widely distributed in nature, being mostly found in many extreme locations such as hot springs, hydrothermal vents, marine trenches, hay composts, etc. Geobacillus species have been widely exploited in various industrial and biotechnological applications, and thus are promising candidates for further studies in the future.