Potential of formulated Dyadobacter jiangsuensis strain 12851 for enhanced bioremediation of chlorpyrifos contaminated soil.

Chlorpyrifos (O, O-diethyl O-3, 5, 6-trichloropyridin-2-yl phosphorothioate) is a toxic and chlorinated organic contaminant in soils across the globe. The present study examines the chlorpyrifos (CP) degrading potential of gram-negative bacterium Dyadobacter jiangsuensis (MTCC 12851), to be a promising and sustainable remedial approach. The proliferation of D. jiangsuensis in the chlorpyrifos spiked minimal salt media indicated the ability of this strain to utilize CP as a sole carbon source and also confirmed the utilization of 3,5,6- trichloro-2-pyridinyl (TCP) through silver nitrate assay. The strain 12851 degraded 80.36% and 76.93% chlorpyrifos (CP) in aqueous medium and soil environment, respectively. The water dispersible granules (WDG) of 45% (v/w) inoculum (bacterial suspension) were developed using talcum powder, acacia gum and alginic acid as key ingredients. The formulated strain (12851) achieved 21.13% enhanced CP degradation in soil under microcosm condition as compared to the unformulated one on 15th day of the treatment. The intermediate metabolites namely 3,5,6-trichloro-2-pyridinol (TCP), tetrahydropyridine, thiophosphate and phenol, 1, 3-bis (1,1-dimethylethyl) were detected during the CP degradation. The current investigation reveals D. jiangsuensis as a potential microbe for CP degradation and opens up the possibility of exploiting its formulations to remediate the CP polluted soils.

Hymenobacter lutimineralis sp. nov., belonging to the family Hymenobacteraceae, isolated from zeolite.

A red-pigmented bacterial strain, designated KIGAM108T, within the family Hymenobacteraceae was isolated from zeolite in the Gampo-41 mine of the Gyeongju, Republic of Korea. This strain was a Gram-negative, strictly aerobic, non-spore forming, rod-shaped bacterium. Phylogenetic analysis of the 16S rRNA gene sequence of strain KIGAM108T found that it was related to the genus Hymenobacter, with similarities of 96.6, 96.4, 95.5, and 95.0% to H. fastidiosus VUG-A124T, H. algoricola VUG-A23aT, H. crusticola MIMBbqt21T, and H. daecheongensis DSM 21074T, respectively. Strain KIGAM108T grew in the presence of 0-0.5% (w/v) NaCl at 4-37 °C and pH 6.0-10.0. This isolate contained MK-7 as a respiratory quinone. The polar lipids of strain KIGAM108T were identified as phosphatidylethanolamine, two unidentified aminophospholipids, one unidentified phospholipid and five unidentified lipids. The major fatty acids profile showed summed feature 3 (C16:1ω6c and/or C16:1ω7c) (22.3%), anteiso-C15:0 (17.1%), C16:1ω5c (13.3%), and iso-C15:0 (11.0%). The genomic DNA G + C content was 60.0 mol%. Based on the polyphasic taxonomic data, strain KIGAM108T is considered to represent a novel species of the genus Hymenobacter, for which the name Hymenobacter lutimineralis sp. nov. is proposed. The type strain is KIGAM108T (=KCTC 72263T =JCM 33444T).

Stable Establishment of Cardinium spp. in the Brown Planthopper Nilaparvata lugens despite Decreased Host Fitness.

The brown planthopper Nilaparvata lugens (Hemiptera) is a major pest of rice crops in Asia. Artificial transinfections of Wolbachia have recently been used for reducing host impacts, but transinfections have not yet been undertaken with another important endosymbiont, Cardinium This endosymbiont can manipulate the reproduction of hosts through phenotypes such as cytoplasmic incompatibility (CI), which is strong in the related white-backed planthopper, Sogatella furcifera (Hemiptera). Here, we stably infected N. lugens with Cardinium from S. furcifera and showed that it exhibits perfect maternal transmission in N. lugens The density of Cardinium varied across developmental stages and tissues of the transinfected host. Cardinium did not induce strong CI in N. lugens, likely due to its low density in testicles. The infection did decrease fecundity and hatching rate in the transinfected host, but a decrease in fecundity was not apparent when transinfected females mated with Wolbachia-infected males. The experiments show the feasibility of transferring Cardinium endosymbionts across hosts, but the deleterious effects of Cardinium on N. lugens limit its potential to spread in wild populations of N. lugens in the absence of strong CI.IMPORTANCE In this study we established a Cardinium-infected N. lugens line that possessed complete maternal transmission. Cardinium had a widespread distribution in tissues of N. lugens, and this infection decreased the fecundity and hatching rate of the host. Our findings emphasize the feasibility of transinfection of Cardinium in insects, which expands the range of endosymbionts that could be manipulated for pest control.

Spirosoma sordidisoli sp. nov., a propanil-degrading bacterium isolated from a herbicide-contaminated soil.

A novel Gram-stain negative, aerobic, rod-shaped, asporogenous, propanil-degrading bacterial strain, TY50T, was isolated from a herbicide-contaminated soil in Nanjing, China. Strain TY50T was found to grow optimally at pH 9.0, 30 °C and in the absence of NaCl. The G + C content of the total DNA was determined to be 55.5 mol%. The 16S rRNA gene sequence of strain TY50T shows high identity to that of Spirosoma lacussanchae CPCC 100624T (99.3%), Spirosoma metallicum PR1014kT (94.8%) and Spirosoma soli MIMBbqt12T (94.6%). DNA-DNA hybridization indicated that the isolate had relatively low levels of DNA-DNA relatedness with S. lacussanchae CPCC 100624T (48.3%). Average nucleotide identity and the digital DNA-DNA hybridizations for draft genomes between strain TY50T and S. lacussanchae CPCC 100624T were 93.2% and 51.0%, respectively. The major cellular fatty acids of strain TY50T were identified as C16:1ω5c (24.5%) and summed feature 3 (C16:1ω6c/C16:1ω7c, 40.7%). MK-7 was found to be the predominant respiratory quinone. The major polar lipid profile includes phosphatidylethanolamine, an unidentified lipid and an unidentified aminolipid. These chemotaxonomic data support the affiliation of strain TY50T with the members of the genus Spirosoma. Strain TY50T can be distinguished from its close phylogenetic neighbours based on its phenotypic, genotypic, and chemotaxonomic features. Therefore, strain TY50T represents a novel member of the genus Spirosoma, for which the name Spirosoma sordidisoli sp. nov. is proposed. The type strain is TY50T (= KCTC 62494T = CCTCC AB 2018041T).

Runella soli sp. nov., isolated from garden soil.

A Gram-stain negative, aerobic, salmon-pink, non-motile and rod-shaped bacterium, designated strain 15J11-1T, was isolated from a soil sample collected from the university garden in Nowongu, South Korea. The 16S rRNA gene sequence analysis showed that strain 15J11-1T is phylogenetically related to Runella slithyformis DSM 19594T and Runella palustris HMF3829T (96.9% and 95.4% sequence similarity, respectively). The major fatty acids of strain 15J11-1T were identified as iso-C15:0, iso-C17:0 3-OH, C16:1ω5c and summed feature 3 (C16:1ω7c and/or C16:1ω6c). The predominant respiratory quinone was identified as MK-7. The polar lipids were found to comprise of phosphatidylethanolamine, three unidentified aminolipids, five unidentified glycolipids, two unidentified aminoglycolipids, an unidentified phospholipid and an unidentified polar lipid. The G + C content in the genomic DNA of the strain 15J11-1T was determined to be 49.9 mol%. Based on the results of genotypic, phenotypic and chemotaxonomic analyses, strain 15J11-1T is concluded to represent a novel species of the genus Runella, for which the name Runella soli sp. nov. (type strain 15J11-1T = KCTC 52021T = NBRC 112817T) is proposed.

Bacterial endosymbiont Cardinium cSfur genome sequence provides insights for understanding the symbiotic relationship in Sogatella furcifera host.

BACKGROUND: Sogatella furcifera is a migratory pest that damages rice plants and causes severe economic losses. Due to its ability to annually migrate long distances, S. furcifera has emerged as a major pest of rice in several Asian countries. Symbiotic relationships of inherited bacteria with terrestrial arthropods have significant implications. The genus Cardinium is present in many types of arthropods, where it influences some host characteristics. We present a report of a newly identified strain of the bacterial endosymbiont Cardinium cSfur in S. furcifera. RESULT: From the whole genome of S. furcifera previously sequenced by our laboratory, we assembled the whole genome sequence of Cardinium cSfur. The sequence comprised 1,103,593 bp with a GC content of 39.2%. The phylogenetic tree of the Bacteroides phylum to which Cardinium cSfur belongs suggests that Cardinium cSfur is closely related to the other strains (Cardinium cBtQ1 and cEper1) that are members of the Amoebophilaceae family. Genome comparison between the host-dependent endosymbiont including Cardinium cSfur and free-living bacteria revealed that the endosymbiont has a smaller genome size and lower GC content, and has lost some genes related to metabolism because of its special environment, which is similar to the genome pattern observed in other insect symbionts. Cardinium cSfur has limited metabolic capability, which makes it less contributive to metabolic and biosynthetic processes in its host. From our findings, we inferred that, to compensate for its limited metabolic capability, Cardinium cSfur harbors a relatively high proportion of transport proteins, which might act as the hub between it and its host. With its acquisition of the whole operon related to biotin synthesis and glycolysis related genes through HGT event, Cardinium cSfur seems to be undergoing changes while establishing a symbiotic relationship with its host. CONCLUSION: A novel bacterial endosymbiont strain (Cardinium cSfur) has been discovered. A genomic analysis of the endosymbiont in S. furcifera suggests that its genome has undergone certain changes to facilitate its settlement in the host. The envisaged potential reproduction manipulative ability of the new endosymbiont strain in its S. furcifera host has vital implications in designing eco-friendly approaches to combat the insect pest.

Spirosoma pomorum sp. nov., isolated from apple orchard soil.

A Gram-negative, motile, rod-shaped, aerobic bacterial strain, designated S7-2-11T, was isolated from apple orchard soil from Gyeongsangnam-do Province, Republic of Korea, and was characterized taxonomically using a polyphasic approach. 16S rRNA gene sequence analysis indicated that strain S7-2-11T belongs to the family Cytophagaceae in phylum Bacteroidetes, and is closely related to Spirosoma luteolum 16F6ET (94.2% identity), Spirosoma knui 15J8-12T (92.7%), and Spirosoma linguale DSM 74T (91.0%). The G + C content of the genomic DNA of strain S7-2-11T was 49.8 mol%. Strain S7-2-11T contained summed feature 3 (C16:1 ω7c/C16:1 ω6c; 35.1%), C16:1 ω5c (22.4%), C15:0 iso (13.9%), and C17:0 iso 3-OH (10.6%) as major cellular fatty acids, and MK-7 as the predominant respiratory quinone. The main polar lipids were phosphatidylethanolamine, an unidentified aminophospholipid, and two unidentified polar lipids. Phenotypic and chemotaxonomic data supported the affiliation of strain S7-2-11T with the genus Spirosoma. The results of physiological and biochemical tests showed the genotypic and phenotypic differentiation of the isolate from recognized Spirosoma species. On the basis of its phenotypic properties, genotypic distinctiveness, and chemotaxonomic features, strain S7-2-11T represents a novel species of the genus Spirosoma, for which the name Spirosoma pomorum sp. nov. is proposed. The type strain is S7-2-11T (= KCTC 52726T = JCM 32130T).

Spirosoma harenae sp. nov., a Bacterium Isolated from a Sandy Beach.

A Gram-stain-negative, non-motile, non-spore-forming, rod-shaped, aerobic bacterium, designated 15J8-9T, was isolated from a sandy beach in Jeju Island, South Korea. The isolate was able to grow between 10 and 30 °C, pH 5-8, and in presence of 0-1% (w/v) NaCl. Based on 16S rRNA gene phylogenetic analysis, the novel strain was closely related to members of the genus Spirosoma (96.1-90.9% similarities) and showed highest sequence similarity to Spirosoma panaciterrae DSM 21099T (96.1%). The G + C content of the genomic DNA of strain 15J8-9T was 45.1 mol%. The isolate contained menaquinone MK-7 as the predominant respiratory quinone, phosphatidylethanolamine as the major polar lipid, and summed feature 3 (C16:1 ω6c/C16:1 ω7c; 28.0%), C16:1 ω5c (23.4%), iso-C15:0 (13.5%), and C16:0 (11.5%) as the major fatty acids that supported the affiliation of strain 15J8-9T to the genus Spirosoma. The isolate could be differentiated clearly from recognized Spirosoma species on the basis of several phenotypic, genotypic and chemotaxonomic features. Therefore, strain 15J8-9T is considered to represent a novel species of the genus the genus Spirosoma, for which the name Spirosoma harenae sp. nov. is proposed. The type strain is 15J8-9T (= KCTC 52030T = JCM 31993T).

Spirosoma gilvum sp. nov., Isolated from Beach Soil.

A Gram-reaction-negative, nonmotile, rod-shaped, aerobic bacterial strain, designated 15J10-9T5T, was isolated from beach soil on Jeju Island, South Korea, and was characterized taxonomically using a polyphasic approach. Comparative 16S rRNA gene sequence analysis showed that the isolate belonged to the family Cytophagaceae in the phylum Bacteroidetes, and was most closely related to Spirosoma aerolatum PR1012kT (96.1%) and Spirosoma panaciterrae DSM 21099T (95.7%). The detection of menaquinone MK-7 as the predominant respiratory quinone, a fatty acid profile with summed feature 3 (C16:1 ω7c/C16:1 ω6c), C16:1 ω5c, and iso-C15:0 as the major components, and a polar lipid profile with phosphatidylethanolamine as the major component also supported the affiliation of strain 15J10-9T5T in the genus Spirosoma. The G+C content of the genomic DNA was 47.7 mol %. The isolate could be clearly differentiated from its closest neighbors based on its phenotypic, phylogenetic, chemotaxonomic, and genotypic features. Therefore, strain 15J10-9T5T represents a novel species of the genus Spirosoma, for which the name Spirosoma gilvum sp. nov. is proposed. The type strain is 15J10-9T5T (=KCTC 52033T = JCM 31997T).

Spirosoma luteolum sp. nov. isolated from water.

A novel Gram-negative and rod-shaped bacterial strain, designated as 16F6ET, was isolated from a water sample. Cells were yellowish in color and catalase- and oxidase-positive. The strain grew at 10-37°C (optimum at 25°C) but not at 4 and 42°C, and pH 5-7 (optimum at pH 7). It showed moderate resistance to gamma-ray irradiation. Comparative phylogenetic analysis showed that strain 16F6ET belonged to the family Cytophagaceae of the class Cytophagia. Furthermore, this isolate showed relatively low 16S rRNA gene sequence similarities (90.7-93.1%) to the members of the genus Spirosoma. The major fatty acids were summed feature 3 (C16:1 ω7c/C16:1 ω6c), C16:1 ω5c, C16:0 N alcohol, and C16:0. The polar lipid profile indicated presence of phosphatidylethanolamine, unknown aminophospholipids, an unknown amino lipid, unknown phospholipids, and unknown polar lipids. The predominant isoprenoid quinone was MK-7. The genomic DNA G+C content of strain 16F6ET was 56.5 mol%. Phenotypic, phylogenetic, and chemotaxonomic properties indicated that isolate 16F6ET represents a novel species within the genus Spirosoma, for which the name Spirosoma luteolum sp. nov. is proposed. The type strain is 16F6ET (=KCTC 52199T =JCM 31411T).

Interplay between microbial trait dynamics and population dynamics revealed by the combination of laboratory experiment and computational approaches.

Filament formation is a common bacterial defense mechanism and possibly has a broad impact on microbial community dynamics. In order to examine the impact of filament formation on population dynamics, we developed an experimental system with a filamentous bacterium Flectobacillus sp. MWH38 and a ciliate predator Tetrahymena pyriformis. In this system, the effective defense of Flectobacillus resulted in the extinction of Tetrahymena by allowing almost no population growth. The result of a kairomone experiment suggested the existence of chemical signals for filament formation. To examine the mechanism further, we developed a quantitative mechanistic model and optimized the model for the experimental result using the simulated annealing method. We also performed a global parameter sensitivity analysis using an approximated Bayesian computation based on the sequential Monte Carlo method to reveal parameters to which the model behavior is sensitive to. Our model reproduced the population dynamics, as well as the cell size dynamics of Flectobacillus. The model behavior is sensitive to the nutrient uptake of Flectobacillus and the propensity of filament formation. It robustly predicts the extinction of Tetrahymena at the condition used in the experiment and predicts the transition from equilibrium to population cycle at higher nutrient conditions. Contrary to the previous study that disproved the presence of chemical signals for filament formation, our result suggested the importance of chemical signals at low predator density, suggesting the variety in bacterial resistance mechanisms that act at different stages of predator-prey interactions.

Symbiont-derived sphingolipids modulate mucosal homeostasis and B cells in teleost fish.

Symbiotic bacteria and mucosal immunoglobulins have co-evolved for millions of years in vertebrate animals. Symbiotic bacteria products are known to modulate different aspects of the host immune system. We recently reported that Flectobacillus major is a predominant species that lives in the gill and skin mucosal surfaces of rainbow trout (Oncorhynchus mykiss). F. major is known to produce sphingolipids of a unique molecular structure. Here we propose a role for F. major and its sphingolipids in the regulation of B cell populations in rainbow trout, as well as an essential role for sphingolipids in trout mucosal homeostasis. We found that F. major-specific IgT titers are confined to the gill and skin mucus, whereas F. major-specific IgM titers are only detected in serum. Live F. major cells are able to stimulate sustained IgT expression and secretion in gills. F. major sphingolipids modulate the growth of trout total skin and gill symbiotic bacteria. In vivo systemic administration of F. major sphingolipids changes the proportion of IgT+ to IgM+ B cells in trout HK. These results demonstrate the key role of the symbiont F. major and its sphingolipids in mucosal homeostasis via the modulation of mucosal and systemic Igs and B cells.

Hymenobacter humi sp. nov., a bacterium isolated from soil.

A red-pink coloured, Gram-negative, rod-shaped bacterium designated as strain DG31A(T) was isolated from soil collected in Seoul, South Korea. The isolate was found to grow optimally at 25 °C on R2A agar. The highest degrees of 16S rRNA gene sequence similarities of the strain were found with Hymenobacter arizonensis JCM 13504(T) (98.0 %), Hymenobacter glaciei VUG-A130(T) (96.1 %), Hymenobacter soli PB17(T) (95.2 %), Hymenobacter antarcticus VUG-A42aa(T) (94.7 %) and Hymenobacter chitinivorans Txc1(T) (92.8 %). The DNA G+C content of the novel strain, DG31A(T), was determined to be 60.8 mol%. Chemotaxonomic data revealed that the major fatty acids were summed feature 3 (C16:1 ω7c and/or C16:1 ω6c; 26.7 %), C16:1 ω5c (18.9 %) and anteiso-C15:0 (12.9 %); the major polar lipid was identified as phosphatidylethanolamine; the polyamine pattern was found to contain sym-homospermidine; and the major quinone was identified as MK-7. The DNA-DNA relatedness of strain DG31A(T) with respect to H. arizonensis JCM 13504(T) was 19.5 ± 2.9 % (reciprocal, 19.3 ± 0.6 %). Based on these data, strain DG31A(T) should be classified within the genus Hymenobacter as a novel species for which the name Hymenobacter humi sp. nov. is proposed, with the type strain DG31A(T) (=KCTC 32523(T) = JCM 19635(T)).

Hymenobacter terrae sp. nov., a bacterium isolated from soil.

A Gram-negative, UV tolerant bacterial strain, DG7A(T), was isolated from soil samples collected in Seoul city, South Korea. The cells were grown on R2A agar at 25 °C and were pink to red in color. The DNA G+C content of the novel strain DG7A was 63.5 mol%. Chemotaxonomic data revealed that the strains contain the major fatty acids iso-C15:0, anteiso-C15:0, and summed feature 3 (16:1 ω7c/16:1 ω6c), with phosphatidylethanolamine as the major polar lipid. Phylogenetic analysis of the 16S rRNA gene sequences showed that strain DG7A(T) formed a distinct phylogenetic line along with Hymenobacter soli PB17(T), and they shared approximately 98.35 % 16S rRNA gene sequence similarity. However, these two strains shared only 5.3 % pairwise similarity (reciprocal analysis, 36.3 %) in their genomic DNA. The next highest degree of 16S rRNA gene sequence similarity after H. soli PB17(T) was found with H. glaciei VUG-A130(T) (96.78 %), H. antarcticus VUG-A42aa(T) (96.66 %), and H. saemangeumensis GSR0100(T) (96.57 %). Based on the phylogenetic analysis and analysis of the physiological and biochemical characteristics, this isolate was considered to represent a novel species, for which we propose the name Hymenobacter terrae sp. nov., with type strain DG7A(T) (= KCTC 32554(T) = KEMB 9004-164(T )= JCM 30007(T)).

Pontibacter humi sp. nov., isolated from mountain soil.

A Gram-negative, aerobic, non-motile, rod-shaped bacterial strain, designated as SWU8(T), was isolated from a mountain soil collected in Seoul Women's University campus at South Korea. Phylogenic analysis, using 16S rRNA gene sequence of the new isolate, showed that strain SWU8(T) belongs to the genus Pontibacter. The highest sequence similarities were 96.2 % with Pontibacter saemangeumensis GCM0142(T), 95.5 % with Pontibacter toksunensis ZLD-7(T), 95.3 % with Pontibacter roseus DSM 17521(T), and 95.1 % with Pontibacter odishensis JC130(T). Chemotaxonomic data showed that the most abundant fatty acids were summed feature 4 (comprising iso-C(17:1) I/anteiso-C(17:1) B; 26.9 %), iso-C(15:0) (25.6 %), and iso-C(17:0) 3OH (10.6 %), and major polar lipid was phosphatidylethanolamine. The DNA G+C content of strain SWU8(T) was 48.5 mol%. Together, the phenotypic, phylogenetic, and chemotaxonomic data supported that strain SWU8(T) presents a novel species of the genus Pontibacter, for which the name Pontibacter humi sp. nov. is proposed. The type strain is SWU8(T) (=KEMC 9004-131(T) = JCM 19178(T)).

Spirosoma radiotolerans sp. nov., a gamma-radiation-resistant bacterium isolated from gamma ray-irradiated soil.

A Gram-negative, short-rod-shaped bacterial strain with gliding motility, designated as DG5A(T), was isolated from a rice field soil in South Korea. Phylogenic analysis using 16S rRNA gene sequence of the new isolate showed that strain DG5A(T) belong to the genus Spirosoma in the family Spirosomaceae, and the highest sequence similarities were 95.5 % with Spirosoma linguale DSM 74(T), 93.4 % with Spirosoma rigui WPCB118(T), 92.8 % with Spirosoma luteum SPM-10(T), 92.7 % with Spirosoma spitsbergense SPM-9(T), and 91.9 % with Spirosoma panaciterrae Gsoil 1519(T). Strain DG5A(T) revealed resistance to gamma and UV radiation. Chemotaxonomic data showed that the most abundant fatty acids were summed feature C(16:1) ω7c/C(16:1) ω6c (36.90 %), C(16:1) ω5c (29.55 %), and iso-C(15:0) (14.78 %), and the major polar lipid was phosphatidylethanolamine (PE). The DNA G+C content of strain DG5A(T) was 49.1 mol%. Together, the phenotypic, phylogenetic, and chemotaxonomic data supported that strain DG5A(T) presents a novel species of the genus Spirosoma, for which the name Spirosoma radiotolerans sp. nov., is proposed. The type strain is DG5A(T) (=KCTC 32455(T) = JCM19447(T)).

Complete genome sequence of Hymenobacter swuensis, an ionizing-radiation resistant bacterium isolated from mountain soil.

Hymenobacter swuensis is a gamma-radiation resistant bacterium isolated from mountain soil in South Korea (N 35°51'38″, E 127°44'47″; altitude 1500m). The complete genome of H. swuensis consists of one chromosome (4,904,241bp) with three plasmids. The genomic sequence indicated that H. swuensis includes a series of genes involved in 2'-hydroxy-carotenoid biosynthesis. This is the first report describing the Hymenobacter genome and key enzymes in the 2'-hydroxy-carotenoid biosynthesis pathway. These data may provide opportunities for genetic engineering and antioxidant 2'-hydroxy-carotenoid production.

Hymenobacter qilianensis sp. nov., isolated from a subsurface sandstone sediment in the permafrost region of Qilian Mountains, China and emended description of the genus Hymenobacter.

A red-pink, Gram-negative, rod-shaped, non-motile, non-spore-forming bacterium, designated strain DK6-37 was isolated from the permafrost region of Qilian Mountains in northwest of China. Phylogenetic analysis based on 16S rRNA gene sequencing indicated that this isolate represents a novel member of the genus Hymenobacter, with low sequence similarities (<97 %) to recognized Hymenobacter species. Optimum growth was observed at 28 °C, pH 7.0 and 0 % NaCl. The strain was found to contain MK-7 as the predominant menaquinone. The polar lipids were identified as phosphatidylethanolanmine, two unknown aminophospholipids, one unknown aminolipid and three unknown polar lipids. The major fatty acids were identified as summed feature 3 (C16:1 ω7c/C16:1 ω6c as defined by MIDI), summed feature 4 (anteiso-C17:1 B/iso-C17:1 I), C16:1 ω5c, iso-C17:0 3-OH, iso-C15:0 and C18:0. The DNA G + C content was determined to be 67.4 mol %. On the basis of the polyphasic evidence presented, it is proposed that strain DK6-37 represents a novel species of the genus Hymenobacter, for which the name Hymenobacter qilianensis sp. nov. is proposed. The type strain is DK6-37(T) (= CGMCC 1.12720(T) = JCM 19763(T)).

Description of Hymenobacter arizonensis sp. nov. from the southwestern arid lands of the United States of America.

Strain OR362-8(T) was isolated from a biological soil crust sample collected from the southwestern arid lands of the United States of America, using BG11-PGY medium. Cells of OR362-8(T) were found to be rod shaped; occur singly, as pairs and in groups; non-motile; positive for catalase, oxidase, phosphatase and gelatinase; hydrolyze starch; contain iso-C(15:0), anteiso-C(15:0), iso-C(15:1)G, C(16:1ω5c) and summed feature 3 (C(16:1(ω7c))/iso-C(15:0) 2OH as defined by the MIDI system) as the major fatty acids; and MK-7 as the sole respiratory quinone. A BLAST sequence similarity search using 16S rRNA gene sequence of OR362-8(T) identified Hymenobacter as the nearest genus with a similarity of 90.4-96.9 %. The phylogenetic analyses based on the phenetic methods UPGMA, NJ, ME and DNA parsimony resulted in the clustering of OR362-8(T) with Clade 1 Hymenobacter species represented by Hymenobacter glaciei, Hymenobacter antarcticus, Hymenobacter flocculans, Hymenobacter metalli and Hymenobacter soli with the closest being the Hymenobacter glaciei (96.9 % 16S rRNA gene sequence similarity). Besides the strong phylogentic affiliation, OR362-8(T) also exhibited significant phenotypic and chemotaxonomic differences with the members of Clade 1 Hymenobacter spp. More importantly, the DNA G+C content (mol%) of OR362-8(T) is very high (70 %) compared to the nearest species identified by phylogenetic analysis. Based on the phylogenetic, phenotypic and chemotaxonomic characteristics, OR362-8(T) was assigned to a novel species for which we propose here the name Hymenobacter arizonensis sp. nov., with OR362-8(T) (=ATCC BAA 1266(T) = DSM 17860(T) = JCM 13504(T)) as the type strain.