Pinirhizobacter soli gen. nov., sp. nov., a novel low temperature resistant gammaproteobacterium in the family Rhodanobacteraceae isolated from rhizospheric soil of Larix gmelinii.

Three yellow-colored strains, NC2-4-308T, NC3-4-326 and NA3-4-109, were isolated from the rhizosphere soil of Larix gmelinii in Nanwenghe Nature Reserve, Great Khingan, China. These strains were oxidase- and catalase-positive and Gram-staining-negative. The cells were non-motile short rods that were aerobic and non-spore-forming. Growth occurred at pH values of 5.0-8.0 and at 0-4% (w/v) NaCl. The three strains were resistant to low temperature and grew at 2-35 °C. The principal fatty acids (> 5%) were summed feature 9, iso-C15:0, iso-C17:0 and anteiso-C15:0. The predominant quinone was ubiquinone-8. The polar lipids consisted of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine, two unidentified phospholipids, three unidentified lipids and three unidentified aminophospholipids. The DNA G + C content of the type species was 64.0 mol%. The 16S rRNA gene sequence similarities among the three strains are more than 99.9%, indicating they belong to the same species. Phylogenetic analysis of the 16S rRNA gene, whole-genome sequences, the low ANI (74.2-75.5%) and dDDH (19.3-20.1%) hybridization values enabled differentiation of strains NC2-4-308T, NC3-4-326 and NA3-4-109 from the members of related genera. The combined data from the morphological, physiological, biochemical and chemotaxonomic tests indicate the three strains as a novel genus and a novel species in the family Rhodanobacteraceae. Therefore, we propose a novel genus with the name Pinirhizobacter soli gen. nov., sp. nov., for which the type strain is NC2-4-308T (= CFCC 14693T = KCTC 72394T).

Rhizobium quercicola sp. nov., isolated from the leaf of Quercus variablis in China.

Strain DKSPLA3T, a novel Gram-negative, catalase-positive, oxidase-positive, non-spore-forming, aerobic, non-nitrogen-fixing, non-motile bacterium was isolated from Quercus variablis leaf, in Zunyi, Guizhou, China. Growth occurred at 4-37 °C (optimum 28 °C), pH 4.0-9.0 (optimum pH 7.0) and up to 4.0% (w/v) NaCl (optimum under 2.0%, w/v). Phylogeny based on 16S rRNA gene indicated that strain DKSPLA3T was a novel species in the genus Rhizobium, which was supported by average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values. The predominant fatty acids of strain DKSPLA3T were C16:0, C18:1 ω7c and/or C18:1 ω6c and C18:1 ω7c 11-methyl. The major respiratory quinone was Q-10. Major polar lipids were diphosphatidyl glycerol (DPG), phosphatidyl glycerol (PG), phosphatidylethanolamine (PE), phosphatidylmonomethylethanolamine (PME), phosphatidylcholine (PC), two unidentified phospholipids (PL) and nine unidentified lipids (L). The genomic G + C content was 64.47 mol%. Based on the phenotypic, phylogenetic and genotypic data, DKSPLA3T should be classified as a novel species in the genus Rhizobium, for which the name Rhizobium quercicola sp. nov. (KCTC 82843T = CFCC 16,707T) is proposed.

Affinibrenneria salicis gen. nov. sp. nov. isolated from Salix matsudana bark canker.

L3-3HAT, a Gram-negative-staining, facultatively anaerobic, motile bacterial strain, was isolated from the symptomatic bark of Salix matsudana canker in China. 16S rRNA gene analysis revealed that the novel strain shares the highest sequence similarity with Brenneria goodwinii FRB141T (95.5%). In phylogenetic trees based on four housekeeping genes (gyrB, rpoB, atpD, and infB) and the 16S rRNA gene sequence, the novel strain formed a separate branch from the five genera of the family Pectobacteriaceae (Lonsdalea, Brenneria, Dickeya, Pectobacterium, and Sodalis), suggesting that the novel strain should belong to a novel species of a novel genus within the family Pectobacteriaceae. The result was also supported by phylogenomics, amino acid identity and average nucleotide identity. The major fatty acids were C14:0, C16:0, C17:0 cyclo, and C19:0 cyclo É·8c. Genome analysis showed that the novel strain has a large genome (5.89 Mb) with 5,052 coding genes, including 181 virulence genes by searching the pathogen-host interactions database (PHI-base), indicating that the novel strain is a potential pathogen of plants and animals. Based on phenotypic and genotypic characteristics, the L3-3HAT strain represents a novel species of a novel genus in the Pectobacteriaceae family, for which the name Affinibrenneria salicis gen nov. sp. nov. is proposed. The strain type is L3-3HAT (= CFCC 15588T = LMG 31209T).

Noviherbaspirillum aerium sp. nov., isolated from air.

A Gram-stain-negative, strictly aerobic, non-spore-forming, rod-shaped, motile with polar flagella and pale-orange bacterium, designated strain 122213-3T, was isolated from air, collected at the foot of the Xiangshan Mountain, located in Beijing, PR China. Optimal growth occurred at 28 °C, at pH 7 and in the presence of 0-1 % (w/v) NaCl. Phylogenetic analyses based on 16S rRNA gene sequences revealed that 122213-3T clustered with species of the genus Noviherbaspirillum and formed a distinct sublineage, showing highest similarities to Noviherbaspirillum malthae CC-AFH3T (96.88 %), Noviherbaspirillum massiliense JC206T (95.78 %) and Noviherbaspirillum aurantiacum SUEMI08T (95.78 %). The predominant cellular fatty acids were summed feature 3 (C16 : 1 ω6c and/or C16 : 1 ω7c), summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c) and C16 : 0. The predominant quinone was ubiquinone 8 (Q-8). The polar lipids comprised phosphatidylethanolamine, phosphatidylglycerol, unidentified phospholipid and two unidentified polar lipids. The polyamine pattern showed the presence of putrescine as the major polyamine, with minor amounts of 2-hydroxyputrescine. The DNA G+C content was 60.1 mol%. The phylogenetic analysis and physiological and biochemical data showed that strain 122213-3T should be classified as representing a novel species in the genus Noviherbaspirillum, for which the name Noviherbaspirillum aerium sp. nov. is proposed. The type strain of N. aerium is 122213-3T (=CFCC 14286T=LMG 30131T).

Stenotrophomonas cyclobalanopsidis sp. nov., isolated from the leaf spot disease of Cyclobalanopsis patelliformis.

A Gram-negative, facultatively anaerobic, motile bacterial strain, TPQG1-4T, was isolated from the leaf of Cyclobalanopsis patelliformis with spot disease. The isolate was investigated using the polyphasic taxonomic approach. 16S rRNA gene sequencing and analyzing revealed that the novel strain shares the highest sequence similarity with Stenotrophomonas lactitubi M15T (99.6%), Stenotrophomonas indicatrix WS40T (99.4%), Stenotrophomonas maltophilia IAM 12423T (99.2%) and Stenotrophomonas pavanii LMG 25348T (99.0%). In phylogenetic trees based on 16S rRNA gene sequences, the novel strain branched independently from other species of Stenotrophomonas. Average nucleotide identity values between the novel isolate and S. lactitubi M15T, S. indicatrix WS40T, S. maltophilia IAM 12423T, S. pavanii LMG 25348T, and Pseudomonas geniculata ATCC 19374T were 87.2%, 87.3%, 86.3%, 88.0%, and 81.3%, respectively, suggesting the isolate was a novel species of the genus Stenotrophomonas. The DNA G + C content of TPQG1-4T is 67.1 mol%. The major fatty acids were iso-C15:0 (25.4%) and anteiso-C15:0 (17.0%). The polar lipids of TPQG1-4T included phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, amino phospholipid and phospholipid. Based on phenotypic and genotypic characteristics, the strain represents a novel species in the genus Stenotrophomonas, for which the name Stenotrophomonas cyclobalanopsidis sp. nov. is proposed. The type strain is TPQG1-4T (= CFCC 15341T = LMG 31208T).

Corticimicrobacter populi gen. nov., sp. nov., a member of the family Alcaligenaceae, isolated from symptomatic bark of Populus × euramericana canker.

One Gram-negative aerobic bacterial strain was isolated from the bark tissue of Populus × euramericana and investigated using a polyphasic approach including 16S rRNA gene sequencing and both phenotypic and chemotaxonomic assays. The 16S rRNA gene and housekeeping gene phylogenies suggest that the novel isolate is different from the other genera of the family Alcaligenaceae. The G+C content, major fatty acids, physiological and biochemical data supported the distinctiveness of the novel strain from reference species. The major fatty acids detected in the novel isolate were C16 : 1ω7c and/or C16 : 1ω6c, C16 : 0, C14 : 0 3OH and/or C16 : 1isoI and C18 : 1ω7c. The phospholipid profile of strain d3-2-2T contained diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, aminolipid, aminophospholipid and an unidentified lipid. The quinone of the novel isolate was Q-8. Therefore, based on the data, the strain constitutes a novel species of a novel genus within the family Alcaligenaceae, for which the name Corticimicrobacter populi gen. nov., sp. nov. is proposed. The type strain is 3d-2-2T (=CFCC 11891T=KCTC 52807T).

Sphingobacterium corticibacter sp. nov., isolated from bark of Populus × euramericana.

One Gram-stain negative, aerobic, non-motile bacterial strain, 2c-3T, was isolated from symptomatic canker bark tissue of Populus × euramericana. It was studied by the genome sequence-derived average nucleotide identity (ANI), phylogenetic analysis based on 16S rRNA gene sequences and phenotypic characteristics. 16S rRNA gene data revealed that the novel isolate shares the greatest sequence similarity to Sphingobacterium populi 7Y-4T (97.0 %). The ANI values between the novel isolate and S. populi 7Y-4T was 81.19 %, lower than the proposed species boundary ANI cut-off (95-96 %). The major fatty acids are iso-C15 : 0, C16 : 1ω7c and iso-C17 : 0 3-OH. The polar lipids of the novel isolate included phosphatidylethanolamine, phospholipid, aminophospholipid and unknown lipids (L1-10). The menaquinone of the novel isolate was MK-7. The DNA G+C content was 41.96 mol %. Based on phenotypic and genotypic characteristics, the isolate represents a novel species within the genus Sphingobacterium, for which the name Sphingobacterium corticibacter is proposed. The type strain is 2c-3T (=CFCC 11898T=KCTC 52798T).

Aureimonas populi sp. nov., isolated from poplar tree bark.

Two novel bacterial strains (4M3-2T and 10-107-7) were isolated from poplar tree bark. The strains were Gram-stain-negative facultative aerobes, and produced short rods that were motile because of polar flagella. A phylogenetic tree was reconstructed based on 16S rRNA gene sequences indicating that the two novel strains are related to species of the genus Aureimonas and Aurantimonas. The two novel strains shared the highest 16S rRNA gene sequence similarities with Aureimonasfrigidaquae CW5 7Y-4T (97.1 %) and Aureimonasaltamirensis DSM 21988T (96.6 %)o. The lipids of the novel strain contain diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidylcholine and sulfoquinovosyl diacylglycerol. The presence of a distinct glycolipid (sulfoquinovosyl diacylglycerol) is an important chemotaxonomic feature used to distinguish between species of the genera, Aurantimonas and Aureimonas. Additionally, the DNA-DNA hybridization results indicated that the two novel strains represent a novel taxon distinct from Aureimonas frigidaquae. The results of the 16S rRNA gene sequence analysis, as well as the physiological and biochemical characteristics imply that the two novel strains should be assigned to a novel species, with the proposed name Aureimonas populi sp. nov. The type strain is 4M3-2T (=CFCC 11187T=KCTC 42087T).

Herbaspirillum piri sp. nov., isolated from bark of a pear tree.

A Gram-stain-negative, aerobic, motile bacterial strain, shQ-4T, was isolated from a pear tree in Henan Province, China. The strain grew at 10-41 °C, at pH 4.0-8.0 and in the presence of 1-3 % (w/v) NaCl. It shared highest 16S rRNA gene sequence similarity (96.66 %) with Herbaspirillum chlorophenolicum CPW301T. The phylogenetic tree based on 16S rRNA gene sequences showed that strain shQ-4T formed a distinct branch next to reference species in the genus Herbaspirillum. The profile of major polar lipids of strain shQ-4T contained phosphatidylethanolamine (PE), diphosphatidylglycerol (DPG), phosphatidylglycerol (PG) and an unidentified aminophospholipid (APL). The major respiratory quinone was Q-8. The major fatty acids of this strain were C16 : 0, summed feature 3 (C16 : 1ω6c/C16 : 1ω7c), C17 : 0 cyclo and C18 : 0. Strain shQ-4T is considered to represent a novel species of the genus Herbaspirillum, with the proposed name Herbaspirillum piri sp. nov. The type strain is shQ-4T (=CFCC 14641T=KCTC 52804T).

Sphingomonas aeria sp. nov., isolated from air.

A Gram-negative, aerobic, non-spore-forming, non-motile, yellow-pigmented and rod-shaped bacterial strain, designated B093034T, was isolated from air at the foot of Xiangshan mountain, located in Beijing, China. Cells of strain B093034T were oxidase-negative and catalase-positive. Growth was observed at 4-41 °C, at pH 4.5-10.0 and at 0-7 % (w/v) NaCl. The isolate contained Q-10 as the predominant isoprenoid quinone, summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), C16 : 0 and C14 : 02-OH as the major fatty acids, sym-homospermidine as the major polyamine, and sphingoglycolipid, phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, diphosphatidylglycerol, aminolipid, two unidentified phospholipids and three unidentified polar lipids as the polar lipids. The DNA G+C content was 67.1 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain B093034T grouped with members of the genus Sphingomonas and was closely related to Sphingomonas sanguinis IFO 13937T (96.49 % similarity), Sphingomonas pseudosanguinis G1-2T (96.37 %), Sphingomonas ginsenosidimutansGsoil 1429T (95.99 %) and Sphingomonas endophytica YIM 65583T (95.78 %). On the basis of the polyphasic evidence presented here, strain B093034T represents a novel species of the genus Sphingomonas, for which the name Sphingomonasaeria sp. nov. is proposed. The type strain is B093034T (=CFCC 13949T=LMG 30133T).

Brenneria populi subsp. brevivirga subsp. nov. isolated from symptomatic bark of Populus × euramericana canker, and description of Brenneria populi subsp. populi subsp. nov.

Two Gram-stain-negative, facultatively anaerobic, motile bacterial strains isolated from symptomatic bark of Populus × euramericana canker in China were investigated using a polyphasic approach, including 16S rRNA gene sequencing, multilocus sequence analysis, and biochemical and physiological assays. 16S rRNA gene sequencing indicated that these strains belonged to the genus Brenneria, family Pectobacteriaceae, and had the highest sequence similarity with Brenneria populi CFCC 11963T (98 %). DNA-DNA hybridization experiments revealed DNA-DNA relatedness values of 72.1-78.2 % between the new isolates and strains of B. populi, revealing that these strains belonged to the same species. The 16S rRNA gene sequencing and multilocus sequence analysis suggested that the two novel strains and those of B. populi are phylogenetically closely related but form two clearly separated subgroups. Based on the data, the two novel isolates represent a subspecies of B. populi for which the name B. populi subsp. brevivirga subsp. nov. is proposed with D8-10-4-5T (=CFCC 11935T=KCTC 42841T) as the type strain, with the automatic creation of B. populi subsp. populi subsp. nov. (type strain D9-5T=CFCC 11963T=KCTC 42088T).

Paracoccus aerius sp. nov., isolated from air.

Strain 011410T, isolated from air at the foot of Xiangshan Mountain, Beijing, China, was Gram-reaction-negative, facultatively anaerobic, oval-shaped, motile with two flagella and catalase- and oxidase-positive. Growth of strain 011410T was observed at 4-41 °C (optimum, 30 °C), at pH 4.5-10.0 (optimum, pH 8.0) and at salinities of 0-10 % (w/v) NaCl (optimum, 0-2 %). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain 011410T was a member of the genus Paracoccus and was related most closely to Paracoccus aestuarii B7T (96.62 % similarity) and Paracoccus sediminis CMB17T (96.48 % similarity). The major fatty acid was identified as C18 : 1ω7c, with smaller amounts of C18 : 0, C10 : 0 3-OH and summed feature 2 (C14 : 0 3-OH and/or iso-C16 : 1 I). The predominant respiratory quinone was ubiquinone-10 (Q-10), with Q-9 as a minor component. Polar lipid analysis indicated the presence of diphosphatidylglycerol, phosphatidylglycerol, one unknown phosphoglycolipid, five unknown phospholipids, one unknown aminolipid, one unknown glycolipid and two unknown polar lipids. The DNA G+C content of the strain was 63.5 mol%. On the basis of the data from this polyphasic characterization, strain 011410T represents a novel species, for which the name Paracoccus aerius sp. nov. is proposed. The type strain is 011410T (=CFCC 14285T=KCTC 42845T).

Sphingobacterium corticis sp. nov., isolated from bark of Populus × euramericana.

A Gram-stain negative, aerobic, non-motile bacterial strain, 23D10-4-9T, was isolated from symptomatic canker bark tissue of Populus × euramericana. The isolate grew between 4 and 35 °C, with optimal growth occurring at 25 °C. The species was positive for catalase and negative for oxidase activity. Nitrate was not reduced to nitrite. It showed activities toward ß-galactosidase and ß-glucosidase. Citrate was not utilized. Acid was produced from d-glucose. The major fatty acids were iso-C15 : 0, C16 : 1ω7c and iso-C17 : 0 3-OH. The main polar lipid profiles of the novel isolate included phosphatidylethanolamine, phospholipids and seven unknown lipids. The predominant menaquinone of the novel isolate was MK-7. The DNA G+C content was 40.6 mol%. 16S rRNA gene data revealed that the novel isolate shares the greatest sequence similarity with Sphingobacterium populi 7Y-4T (96.1 %). Based on phenotypic and genotypic characteristics, the isolate represents a novel species within the genus Sphingobacterium, for which the name Sphingobacteriumcorticis sp. nov. is proposed. The type strain is 23D10-4-9T (=CFCC 12640T=KCTC 42248T).

Leucobacter populi sp. nov. isolated from a symptomatic bark of Populus × euramericana canker.

A Gram-stain positive, aerobic, non-motile, rod-shaped, oxidase-negative and catalase-positive bacterial strain, designated 06C10-3-11T, was isolated from the symptomatic bark of a Populus × euramericana canker. Growth occurred at 10-45 °C (optimum, 30 °C), pH 6-11 (optimum, pH 7.0-8.0), 0-7 % (w/v) NaCl (optimum, 0-1 %) and in the presence of 20 mM Cr (VI). The major fatty acids (≥10 %) of the novel strain were identified as anteiso-C15:0, anteiso-C17:0 and iso-C16:0. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phospholipid, glycolipid and two unknown lipids. The strain contained the respiratory quinone MK-10 (71 %) as a major component and MK-11 (29 %) in lesser amounts. The cell wall amino acids were 2,4-diaminobutyric acid, alanine, glutamic acid and glycine. The genomic DNA G+C content of the type strain was 69.8 mol%. Phylogenetic analysis, based on 16S rRNA gene sequences, indicated that strain 06C10-3-11T belongs to the genus Leucobacter, showing the highest 16S rRNA gene sequence similarities with Leucobacter celer NAL101T (96.19 %), 'Leucobacter kyeonggiensis' F3-P9T (96.18 %), Leucobacter denitrificans M1T8B10T (96.10 %) and Leucobacter aridicollis CIP 108388T (96.06 %). The DNA G+C content of strain 06C10-3-11T was 69.8 mol%. Based on the molecular data and physiological and biochemical characteristics, strain 06C10-3-11T is considered to represent a novel species of the genus Leucobacter, for which the name Leucobacterpopuli sp. nov. is proposed. The type strain is 06C10-3-11T (= CFCC 12199T = KCTC 39685T).

Corticibacteriumpopuli gen. nov., sp. nov., a member of the family Phyllobacteriaceae, isolated from bark of Populus×euramericana.

Two Gram-staining-negative, aerobic, motile, slimy, glossy bacterial strains were isolated from bark tissue of Populus×euramericana. The bacteria grew at 10-37 °C, pH 5-10, with optimal growth at 28-30 °C, pH 6.0-8.0. Both strains grew with 0-3 % (w/v) NaCl. In the maximum-likelihood phylogenetic tree, the two isolates formed a distinct branch within the family Phyllobacteriaceae, and they were not closely related to any of the genera within the family Phyllobacteriaceae. The two novel isolates werepositive for oxidase andcatalase activity. The polar lipids profile revealed diphosphatidylglycerol, phosphatidylcholine, phospholipid, phosphatidylethanolamine, phosphatidylglycerol and five unknown lipids. The major fatty acids were C18 : 1ω7c and C16 : 0. The DNA G+C content was 56.4 mol%. On the basis of phylogenetic, chemotaxonomic and phenotypic data, the two strains represent a novel species belonging to a novel genus of the family Phyllobacteriaceae, for which the name Corticibacterium populi gen. nov., sp. nov. is proposed. The type strain of the type species is 16B10-2-7T (=CFCC 12884T=KCTC 42249T).

Description of Altererythrobacter aerius sp. nov., isolated from air, and emended description of the genus Altererythrobacter.

A Gram-stain-negative, yellow-pigmented, ovoid to rod-shaped, strictly aerobic bacterial strain, designated 100921-2T, was isolated from air at the foot of Xiangshan Mountain. Phylogenetic and phenotypic analysis of the organism revealed that the isolate belongs to the genus Altererythrobacter. Strain 100921-2T showed high 16S rRNA gene sequence similarity (96.01-94.70 %) to other type strains of the genus Altererythrobacter, with the highest similarity to Altererythrobactermarensis MSW-14T. Growth of strain 100921-2T was observed at 4-50 °C (optimum, 30 °C), at pH 4.5-10.0 (optimum, pH 7.0) and at salinities of 0-10 % (w/v) NaCl (optimum 0-0.5 %). The major fatty acids were C18 : 1ω7c (27.8 %), C17 : 1ω6c (23.1 %), 11-methyl C18 : 1ω7c(11.9 %), summed feature 3 (9.1 %) and C15 : 0 2-OH (7.9 %). The predominant respiratory quinone was ubiquinone-10 (Q-10). Polar lipid analysis indicated the presence of diphosphatidylglycerol, sphingoglycolipid, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, two unknown phospholipids, five unknown polar lipids and two unknown glycolipids. The DNA G+C content of the type strain was 67.5 mol%. On the basis of the data from the polyphasic characterization, strain 100921-2T represents a novel species, for which the name Altererythrobacter aerius sp. nov. is proposed. The type strain is 100921-2T (=CFCC 14287T=KCTC 42844T).

Description of Acinetobacter populi sp. nov. isolated from symptomatic bark of Populus x euramericana canker.

Five Gram-negative, non-motile, rod-shaped bacterial strains were isolated from cankers of Populus x euramericana collected from different locations in Puyang city, Henan Province, China. The five strains were characterized by nutritional and physiological testing and DNA sequence analysis. Haemolysis was not observed on agar media supplemented with sheep erythrocytes. The strains could be distinguished from members of most species of the genus Acinetobacter by their inability to assimilate L-arginine and benzoate. The five strains formed a single branch in phylogenetic trees based on 16S rRNA, gyrB and rpoB individual gene sequence analysis,indicating that they all belonged to a single taxon within the genus Acinetobacter. DNA-DNA hybridization results indicated that the five isolates represented to a single species that was separate from Acinetobacter puyangensis. On the basis of the phenotypic, genotypic and phylogenetic characteristics, the five strains are considered to represent a novel species of the genus Acinetobacter, for which the name Acinetobacter populi sp. nov. is proposed. The typestrain of A. populi sp. nov. is PBJ7T (CFCC 11170T=KCTC 42272T).

Corticibacter populi gen. nov., sp. nov., a new member of the family Comamonadaceae, from the bark of Populus euramericana.

Three novel endophytic strains, designated 17B10-2-12T, 26C10-4-4 and D13-10-4-9, were isolated from the bark of Populus euramericana in Heze, Shandong Province, China. They were Gram-reaction-negative, aerobic, non-motile, short-rod-shaped, oxidase-positive and catalase-negative. A phylogenetic analysis of the 16S rRNA gene showed that the three novel strains clustered with members of the family Comamonadaceae and formed a distinct branch. The isolates shared 100 % similarities among themselves and had the highest sequence similarity with Xenophilus azovorans DSM 13620T (95.2 %) and Xenophilus arseniciresistens YW8T (95.0 %), and less than 95.0 % sequence similarities with members of other species. Their major fatty acids were C16 : 0, C17 : 0 cyclo, C18 : 1ω7c and C16 : 1ω7c/C16 : 1ω6c. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and three unknown aminophospholipids. The predominant quinone was ubiquinone-8 (Q-8). The DNA G+C content was 69.5­70.0 mol%. Based on data from a polyphasic taxonomy study, the three strains represent a novel species of a novel genus of the family Comamonadaceae, for which the name Corticibacter populi gen. nov., sp. nov. is proposed. The type strain is 17B10-2-12T ( = CFCC 12099T = KCTC 42091T).

Microbacterium populi sp. nov., isolated from Populus×euramericana bark.

Five non-spore-forming, aerobic and Gram-stain-positive bacterial strains, 10-107-8(T), 1C-4, NHI3_6, 4107_1_2, and 3D-3, were isolated from Populus × euramericana bark collected in Puyang City, Henan Province, PR China. The isolates grew at 15-40 °C and pH 5-10. The optimum temperature and pH for growth were 30 °C and pH 8.0, respectively. Chemotaxonomic features included MK-10 and MK-11 as major menaquinones (type strain); predominating iso- and anteiso-branched cellular fatty acids; diphosphatidylglycerol and phosphatidylglycerol as major polar lipids (type strain); ornithine as the principal diamino acid of the cell-wall peptidoglycan (type strain); glycolyl type as cell-wall acyl type; and DNA G+C content of 66.8-67.6 mol%. These features were consistent with classification in the genus Microbacterium . Analysis of 16S rRNA gene sequence data indicated that the five isolates belonged to the genus Microbacterium and were closely related to Microbacterium halotolerans . A high 16S rRNA gene sequence similarity of 96.97% to M. halotolerans YIM 70130(T) was observed. The five isolates showed less than 96.20% 16S rRNA gene sequence similarity to the other species of the genus Microbacterium with validly published names. DNA-DNA relatedness of the five isolates with M. halotolerans JCM 13013(T) ranged from 35.62% to 44.36%. Considering the results of 16S rRNA gene sequence analysis and the physiological and biochemical characteristics, we propose that the five strains should be assigned to a novel species of the genus Microbacterium . The name proposed for the five strains is Microbacterium populi sp. nov., and the type strain is 10-107-8(T) ( =CFCC 11275(T) =KCTC 29152(T)).

Multilocus sequence analysis of the genus Kurthia, and a description of Kurthia populi sp. nov.

Four novel bacterial strains belonging to the genus Kurthia were isolated from the surface of a weevil of the family Curculionidae (strain 10y-14T), and from bark samples of hybrid poplar, Populus × euramericana (strains 6-3, 2-5 and 06C10-3-14), in Puyang, Henan Province, China. Phylogenetic analyses of the 16S rRNA gene and multilocus sequence analysis (MLSA) data showed that the four strains form a distinct cluster in the genus Kurthia, indicating that they all belong to a single taxon within the genus. DNA-DNA hybridization levels between strain 10y-4T and Kurthia huakuii LAM0618T and Kurthia massiliensis DSM 24639T were 58.31 and 53.92 %, respectively. This indicates that the four novel strains represent a species distinct from these two closely related species. The DNA G+C content of the novel strains was 42.1-42.6 %. The major fatty acids were iso-C15 : 0 and anteiso-C15 : 0.The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unknown phospholipid and unidentified aminophospholipids. The predominant menaquinones were MK-7 (90 %) and MK-6 (10 %). The major cell-wall amino acids were lysine, alanine, glutamic acid and glycine. On the basis of the MLSA and 16S rRNA gene sequence phylogenetic analyses, DNA-DNA reassociation values, DNA base composition, and biochemical and phenotypic characteristics, the four strains are considered to represent a novel species within the genus Kurthia, for which the name Kurthia populi sp. nov. is proposed. The type strain is 10y-14T ( = CFCC 11600T = KCTC 33522T).