- Volume 74, Issue 1, 2024

A spherical, pink, aerobic, Gram-stain-positive bacterial strain (MIMF12T) was isolated from rhizosphere soil collected in the Inner Mongolia Autonomous Region, PR China. Cellular growth of the strain was observed at pH 6.0–8.0 (optimum, pH 7.0), at 20–37 °C (optimum, 28 °C) and with 0–1 % (w/v) NaCl (optimum, 0 %). Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain MIMF12T was most closely related to Deinococcus terrestris SDU3-2T with a similarity value of 96.0 %. The respiratory quinone was menaquinone 8, the major fatty acids were C15 : 1  ω6c and C17 : 1  ω8c, and the major polar lipids were composed of two aminophospholipids, one phospholipid and four unidentified lipids. The G+C content of the genomic DNA was 70.1 mol%. The average nucleotide identity and digital DNA–DNA hybridization values between strain MIMF12T and the closest related type strain SDU3-2T were 88.1 and 52.1 %, respectively. The discovery that MIMF12T differs not only from validly named species in the genus Deinococcus , but also from currently unnamed species in the GDTB, gives us new insights into the genus. Based on phenotypic, chemotaxonomic and phylogenetic characteristics, strain MIMF12T represents a novel species of the genus Deinococcus , for which the name Deinococcus rhizophilus sp. nov. is proposed. The type strain is MIMF12T (=CGMCC 1.61579T=KCTC 43572T).

Identified as a newly described species from a biocrust in Svalbard, Norway (78° 54′ 8.27″ N 12° 01′ 20.34″ E), isolate PAP01T has different characteristics from any known predatory bacteria. The isolate was vibrio-shaped strain that employed flagellar motility. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the isolate clustered within the genus Bdellovibrio in the family Bdellovibrionaceae . 16S rRNA gene sequence similarities between strain PAP01T and the type strain ( Bdellovibrio bacteriovorus HD100) was 95.7 %. The PAP01T genome has a size of 3.898 Mbp and possesses 3732 genes and a G+C content of 45.7 mol%. The results of genetic and physiological tests indicated the phenotypic differentiation of strain PAP01T from the two other Bdellovibrio species with validly published names. Based on the physiological and phylogenetic data, as well as the prey range spectrum and osmolality sensitivities, isolate PAP01T represents a novel species within the genus Bdellovibrio , for which the name Bdellovibrio svalbardensis sp. nov. is proposed. The type strain is PAP01T (=KCTC 92583T=DSM 115080T).

Two Gram-stain-negative, facultative anaerobic, rod-shaped bacterial strains, S171T and S2-9, were isolated from seleniferous soil in China. Comprehensive phylogenetic analyses based on 16S rRNA genes, multilocus sequences and whole genome sequences indicated that the two strains belonged to the genus Citrobacter . The average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) values of strains S171T and S2-9 with the closest relative Citrobacter koseri NCTC 10786T were 83.6–83.7% and 27.7–27.8 %, respectively, which were below the species cutoff values. The ANI and dDDH values between the two strains were 97.9% and 84.8 %, respectively. The biochemical characteristics revealed that selenite tolerance, H2S and indole production, arginine dihydrolase, ornithine decarboxylase, as well as acid production from carbon sources such as d-sorbitol and arbutin are distinctive features of the two strains. Based on these results, strain S171T and strain S2-9 represent a novel species of the genus Citrobacter , for which the name Citrobacter enshiensis sp. nov. is proposed, with strain S171T (=GDMCC 1.3637T=JCM 35851T) as the type strain. The genome size of strain S171T was 4.92 Mb with a G+C content of 52.6 mol%. The genome size of strain S2-9 was 4.89 Mb with a G+C content of 52.6 mol%.

A Gram-negative, non-motile, strictly aerobic, rod-shaped bacterium, designated as H12T, was isolated from the sediments of mangrove plant Bruguiera sexangula taken from Dapeng district, Shenzhen, PR China. The pairwise 16S rRNA gene sequence analysis showed that strain H12T shared high identity levels with species of the genus Microbulbifer , with the highest similarity level of 98.5 % to M. pacificus SPO729T, followed by 98.1 % to M. donghaiensis CN85T. Phylogenetic analysis using core-genome sequences showed that strain H12T formed a cluster with type species of M. pacificus SPO729T and M. harenosus HB161719T. The complete genome of strain H12T was 4 481 396 bp in size and its DNA G+C content was 56.7 mol%. The average nucleotide identity and digital DNA–DNA hybridization values among strain H12T and type species of genus Microbulbifer were below the cut-off levels of 95–96 and 70 %, respectively. The predominant cellular fatty acids of strain H12T were iso-C15 : 0 (22.5 %) and C18 : 1  ω7c (13.9 %). Ubiquinone-8 was detected as the major respiratory quinone. The polar lipids of strain H12T comprised one phosphatidylglycerol, one phosphatidylethanolamine, one unidentified aminoglycophospholipid, one unidentified glycophospholipid, three unidentified glycolipids, two unidentified aminolipids, and one unidentified lipid. Based on polyphasic evidence, strain H12T represents a novel species of the genus Microbulbifer , for which the name Microbulbifer bruguierae sp. nov. is proposed. The type strain is H12T (=KCTC 92859T=MCCC 1K08451T). Comparative genomic analyses of strain H12T with strains of the genus Microbulbifer reveal its potential in degradation of pectin.

A novel Gram-stain-negative, facultatively anaerobic and rod-shaped bacterial strain, designated as DAU312T, was isolated from the sea water of the eastern coast of the Republic of Korea. Optimal growth was observed at 25 °C, pH 7.0–8.0 and with NaCl concentrations of 2.0 % (w/v). Catalase and oxidase activities were detected. On the basis of 16S rRNA gene sequences, strain DAU312T showed the highest similarity (99.2 %) to the type strain Shewanella electrodiphila MAR441T. The complete genome sequence of strain DAU312T contains 4 893 483 bp and 40.5 mol% G+C. Phylogenetic analyses based on 16S rRNA gene sequences and the up-to-date bacterial core genes showed that strain DAU312T, S. electrodiphila MAR441T and S. olleyana were all part of the same monophyletic clade. Their average nucleotide identity, digital DNA–DNA hybridization and two-way average amino acid identity values with each other and type strains of close Shewanella species were 83.4–77.5 %, 27.3–22.0 % and 89.8–81.2 %, respectively. The major cellular fatty acids (>10 %) were iso-C15 : 0, summed feature 3 (C16 : 1 ω7с and/or C16 : 1 ω6с) and C16 : 0. Phosphatidylethanolamine and phosphatidylglycerol were the main polar lipids. The respiratory quinones were Q-7, Q-8, MK-7 and MMK-7. Based on these polyphasic taxonomic findings, the name Shewanella goraebulensis sp. nov. is suggested for strain DAU312T, which is considered to represent a novel species of the genus Shewanella . The type strain is DAU312T (=KCTC 72427 T=JCM 35744T=KCCM 43478T).

Two novel indole acetic acid-producing strains, 5MLIRT and D4N7, were isolated from Indosasa shibataeoides in Yongzhou, Hunan province, and Phyllostachys edulis in Hangzhou, Zhejiang province, respectively. Based on their 16S rRNA sequences, strains 5MLIRT and D4N7 were closely related to Comamonas antarcticus 16-35-5T (98.4 % sequence similarity), and the results of 92-core gene phylogenetic trees showed that strains 5MLIRT and D4N7 formed a phylogenetic lineage within the clade comprising Comamonas species. The complete genome size of strain 5MLIRT was 4.49 Mb including two plasmids, and the DNA G+C content was 66.5 mol%. The draft genome of strain D4N7 was 4.26 Mb with 66.7 mol% G+C content. The average nucleotide identity and digital DNA–DNA hybridization values among strain 5MLIRT and species in the genus Comamonas were all below the species delineation threshold. The colonies of strain 5MLIRT and D4N7 were circular with regular margins, convex, pale yellow and 1.0–2.0 mm in diameter when incubated at 30 °C for 3 days. Strains 5MLIRT and D4N7 grew optimally at 30 °C, pH 7.0 and 1.0 % NaCl. The respiratory isoprenoid quinone was ubiquinone-8. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. Polyphasic analyses indicated that strains 5MLIRT and D4N7 could be distinguished from related validly named Comamonas species and represent a novel species of the genus Comamonas , for which the name Comamonas endophytica sp. nov. is proposed. The type strain is 5MLIRT (=ACCC 62069T=GDMCC 1.2958T=JCM 35331T).

A Gram-negative and rod-shaped bacterium, designated C340-1T, was isolated and screened from paddy soil in Zhongshan County, Guangxi Province, PR China. This strain grew at 20–42 °C (optimum, 37 °C), pH 5.0–9.0 (optimum, pH 7.0) and 0–4 % (w/v) NaCl (optimum, 0–1 %) on Reasoner's 2A medium. The strain could fix atmospheric nitrogen and acetylene reduction activity was recorded up to 120.26 nmol ethylene h–1 (mg protein)–1. Q-10 was the only isoprenoid quinone component; phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, an unidentified aminolipid and an unidentified polar lipid were the major polar lipids. Summed feature 8 (C18 : 1  ω7c and/or C18 : 1  ω6c) and summed feature 3 (C16 : 1  ω7c and/or C16 : 1  ω6c) were the primary cellular fatty acids. The genome of strain C340-1T was 6.18 Mb, and the G+C content was 69.0 mol%. Phylogenetic tree analysis based on 16S rRNA gene and 92 core genes showed that strain C340-1T was closely related to and clustered with the type strains Azospirillum brasilense JCM 1224T, Azospirillum argentinense Az39T, Azospirillum baldaniorum Sp245T and Azospirillum formosense JCM 17639T. The average nucleotide identity (ANI), average amino acid identity (AAI) and digital DNA–DNA hybridization (dDDH) values between strain C340-1T and the closely related type strains mentioned above were significantly lower than the threshold values for species classification (95–96 %, 95–96 % and 70 %, respectively). Based on phylogenetic, genomic, phenotypic, physiological and biochemical data, we have reason to believe that C340-1T represents a new species of the genus Azospirillum , for which the name Azospirillum isscasi sp. nov. is proposed. The type strain is C340-1T(=CCTCC AB 2023105T=KCTC 8126T).

A Gram-stain-negative strain, designated as D2M1T was isolated from xylene-degrading enrichment culture and characterized using a polyphasic approach to determine its taxonomic position. The 16S rRNA gene sequence analysis revealed that strain D2M1T belongs to the genus Acidovorax , with the highest 16S rRNA gene similarity to Acidovorax delafieldii DSM 64T (99.93 %), followed by Acidovorax radicis DSM 23535T (98.77 %) and Acidovorax kalamii MTCC 12652T (98.76 %). The draft genome sequence of strain D2M1T is 5.49 Mb long, and the G+C content of the genome is 64.2 mol%. Orthologous average nucleotide identity and digital DNA–DNA hybridization relatedness values between strain D2M1T and its closest relatives were below the threshold values for species demarcation confirming that strain D2M1T is distinctly separated from its closest relatives. The whole genome analysis of the strain revealed a phenol degradation gene cluster, encoding a multicomponent phenol hydroxylase (mPH) together with a complete meta-cleavage pathway including an I.2.C-type catechol 2,3-dioxygenase (C23O) gene. The strain was able to degrade benzene and ethylbenzene as sole sources of carbon and energy under aerobic and microaerobic conditions. Cells were facultatively aerobic rods and motile with a single polar flagellum. The predominant fatty acids (>10 % of the total) of strain D2M1T were summed feature 3 (C16 : 1  ω7c/C16 : 1  ω6c), C16 : 0 and summed feature 8 (C18 : 1  ω7c/C18 : 1  ω6c). The major ubiquinone of strain D2M1T was Q8, while the major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. Based on polyphasic data, it is concluded that strain D2M1T represents a novel species of the genus Acidovorax , for which the name of Acidovorax benzenivorans sp. nov. is proposed. The type strain of the species is strain D2M1T (=DSM 115238T=NCAIM B.02679T).

Five strains of two novel species were isolated from the wastewater treatment systems of a pharmaceutical factory located in Zhejiang province, PR China. Strains ZM22T and Y6 were identified as belonging to a potential novel species of the genus Comamonas , whereas strains ZM23T, ZM24 and ZM25 were identified as belonging to a novel species of the genus Pseudomonas . These strains were characterized by polyphasic approaches including 16S rRNA gene analysis, multi-locus sequence analysis, average nucleotide identity (ANI), in silico DNA–DNA hybridization (isDDH), physiological and biochemical tests, as well as chemotaxonomic analysis. Genome-based phylogenetic analysis further confirmed that strains ZM22T and Y6 form a distinct clade closely related to Comamonas testosteroni ATCC 11996T and Comamonas thiooxydans DSM 17888T. Strains ZM23T, ZM24 and ZM25 were grouped as a separate clade closely related to Pseudomonas nitroreducens DSM 14399T and Pseudomonas nicosulfuronedens LAM1902T. The orthoANI and isDDH results indicated that strains ZM22T and Y6 belong to the same species. In addition, genomic DNA fingerprinting demonstrated that these strains do not originate from a single clone. The same results were observed for strains ZM23T, ZM24 and ZM25. Strains ZM22T and Y6 were resistant to multiple antibiotics, whereas strains ZM23T, ZM24 and ZM25 were able to degrade an emerging pollutant, triclosan. The phylogenetic, physiological and biochemical characteristics, as well as chemotaxonomy, allowed these strains to be distinguished from their genus, and we therefore propose the names Comamonas resistens sp. nov. (type strain ZM22=MCCC 1K08496T=KCTC 82561T) and Pseudomonas triclosanedens sp. nov. (type strain ZM23T=MCCC 1K08497T=JCM 36056T), respectively.

Two Gram-stain-negative, obligately aerobic, motile rod bacteria, designated as G2-5T and G20-9T, exhibiting catalase- and oxidase-positive activities, were isolated from the phycosphere of a Chondrus species, a marine red alga. Strain G2-5T exhibited optimal growth at 30 °C and pH 5.0–6.0 and in the presence of 0.5–1.0% NaCl. In contrast, strain G20-9T demonstrated optimal growth at 25 °C and pH 6.0 and in the presence of 0.5–1.5% NaCl. Both strains contained ubiquinone-10, summed feature 8 (C18 : 1  ω7c and/or C18 : 1  ω6c), C18 : 0 and 11-methyl-C18 : 1  ω7c, and diphosphatidylglycerol and phosphatidylglycerol as the major respiratory isoprenoid quinone, cellular fatty acids and polar lipids, respectively. The genomic DNA G+C contents were 57.2 mol% for strain G2-5T and 57.5 mol% for strain G20-9T. Strains G2-5T and G20-9T exhibited 98.2 % 16S rRNA gene sequence similarity, along with 82.3 % average nucleotide identity (ANI) and 25.0 % digital DNA–DNA hybridization (dDDH) values, indicating that they represent different species. Phylogenetic analyses based on both 16S rRNA gene and genome sequences revealed that strains G2-5T and G20-9T formed distinct phylogenic lineages within the genus Devosia . Strains G2-5T and G20-9T were most closely related to Devosia limi DSM 17137T and Devosia beringensis S02T with 97.7 and 96.9 % 16S rRNA gene sequence similarities, respectively. The ANI and dDDH values between strains G2-5T and G20-9T and other Devosia species were lower than 73.9 and 19.2 %, respectively, suggesting that they constitute novel species within the genus Devosia . Based on their distinct phenotypic, chemotaxonomic, and molecular characteristics, strains G2-5T and G20-9T represent two novel species of the genus Devosia , for which the names Devosia rhodophyticola sp. nov. (G2-5T=KACC 22601T=JCM 35404T) and Devosia algicola sp. nov. (G20-9T=KACC 22650T=JCM 35405T) are proposed, respectively.

Eight Gram-stain-negative bacterial strains were isolated from cheese rinds sampled in France. On the basis of 16S rRNA gene sequence analysis, all isolates were assigned to the genus Halomona s. Phylogenetic investigations, including 16S rRNA gene studies, multilocus sequence analysis, reconstruction of a pan-genome phylogenetic tree with the concatenated core-genome content and average nucleotide identity (ANI) calculations, revealed that they constituted three novel and well-supported clusters. The closest relative species, determined using the whole-genome sequences of the strains, were Halomonas zhanjiangensis for two groups of cheese strains, sharing 82.4 and 93.1 % ANI, and another cluster sharing 92.2 % ANI with the Halomonas profundi type strain. The strains isolated herein differed from the previously described species by ANI values <95 % and several biochemical, enzymatic and colony characteristics. The results of phenotypic, phylogenetic and chemotaxonomic analyses indicated that the isolates belonged to three novel Halomonas species, for which the names Halomonas citrativorans sp. nov., Halomonas casei sp. nov. and Halomonas colorata sp. nov. are proposed, with isolates FME63T (=DSM 113315T=CIRM-BIA2430T=CIP 111880T=LMG 32013T), FME64T (=DSM 113316T=CIRM-BIA2431T=CIP 111877T=LMG 32015T) and FME66T (=DSM 113318T=CIRM-BIA2433T=CIP 111876T=LMG 32014T) as type strains, respectively.

A previously undescribed, heavy-metal-tolerant, motile, Gram-negative bacterium, designated strain SK50-23T, was characterized using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain SK50-23T was closely related to Tardiphaga robiniae LMG 26467T and the non-phototrophic ‘Rhodopseudomonas boonkerdii’ NS23T (98.1 and 97.3 % 16S rRNA gene sequence similarity, respectively). Strain SK50-23T possessed a circular genome of 5.86 Mb, with a DNA G+C content of 61.9 mol%. Digital DNA–DNA hybridization showed 20.8–21.6 % similarity between strain SK50-23T and related species. In addition, the whole-genome average nucleotide identity values between strain SK50-23T and related species ranged from 75.1 to 83.5 %. The major cellular fatty acid identified in strain SK50-23T was C18 : 1ω7c, and the main isoprenoid quinone present was ubiquinone Q-10. Strain SK50-23T could be assigned to the genus Tardiphaga with the species name Tardiphaga alba sp. nov. based on morphological, chemotaxonomic and genome-based taxonomic characteristics, and 16S rRNA gene-based phylogenetic characteristics. The type strain of the proposed novel species is SK50-23T (=NBRC 108825T=CGMCC No. 1.12037T).

A bacterial strain, designated NLS-7T, was isolated through enrichment of landfill cover soil in methane-oxidizing conditions. Strain NLS-7T is a Gram-stain negative, non-motile rod, approximately 0.8 µm wide by 1.3 µm long. Phylogenetic analysis based on 16S rRNA gene sequencing places it within the genus Methylocystis , with its closest relatives being M. hirsuta , M. silviterrae and M. rosea , with 99.9, 99.7 and 99.6 % sequence similarity respectively. However, average nucleotide identity and average amino acid identity values below the 95 % threshold compared to all the close relatives and digital DNA–DNA hybridization values between 20.9 and 54.1 % demonstrate that strain NLS-7T represents a novel species. Genome sequencing generated 4.31 million reads and genome assembly resulted in the generation of 244 contigs with a total assembly length of 3 820 957 bp (N50, 37 735 bp; L50, 34). Genome completeness is 99.5 % with 3.98 % contamination. It is capable of growth on methane and methanol. It grows optimally at 30 °C between pH 6.5 and 7.0. Strain NLS-7T is capable of atmospheric dinitrogen fixation and can use ammonium (as NH4Cl), l-aspartate, l-arginine, yeast extract, nitrate, l-leucine, l-proline, l-methionine, l-lysine and l-alanine as nitrogen sources. The major fatty acids are C18:1 ω8c and C18:1 ω7c. Based upon this polyphasic taxonomic study, strain NLS-7T represents a novel species of the genus Methylocystis , for which the name Methylocystis suflitae sp. nov. is proposed. The type strain is NLS-7T (=ATCC TSD-256T=DSM 112294T). The 16S rRNA gene and genome sequences of strain NLS-7T have been deposited in GenBank under accession numbers ON715489 and GCA_024448135.1, respectively.

A Gram-stain-negative, catalase-positive and oxidase-positive, nonmotile, aerobic, light yellow, spherical-shaped bacterial strain with no flagella, designated strain YIM 152171T, was isolated from sediment of the South China Sea. Colonies were smooth and convex, light yellow and circular, and 1.0–1.5×1.0–1.5 µm in cell diameter after 7 days of incubation at 28°C on YIM38 media supplemented with sea salt. Colonies could grow at 20–45°C (optimum 28–35°C) and pH 6.0–11.0 (optimum, pH 7.0–9.0), and they could proliferate in the salinity range of 0–6.0 % (w/v) NaCl. The major cellular fatty acids were summed feature 8 (C18 : 1  ω7c/C18 : 1 ω6c), C18 : 1 ω7c 11-methyl, C16 : 0, C16 : 1 ω11c, C16 : 1 ω5c, C17 : 1 ω6c and C18 : 1 ω5c. The respiratory quinone was ubiquinone 10, and the polar lipid profile included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, phosphatidylinositol mannoside, one unidentified phospholipid and one unidentified aminolipid. Phylogenetic analyses based on the 16S rRNA gene sequences placed strain YIM 152171T within the order Rhodospirillales in a distinct lineage that also included the genus Geminicoccus . The 16S rRNA gene sequence similarities of YIM 152171T to those of Arboricoccus pini , Geminicoccus roseus and Constrictibacter antarcticus were 92.17, 89.25 and 88.91 %, respectively. The assembled draft genome of strain YIM 152171T had 136 contigs with an N50 value of 134704 nt, a total length of 3 001 346 bp and a G+C content of 70.27 mol%. The phylogenetic, phenotypic and chemotaxonomic data showed that strain YIM 152171T (=MCCC 1K08488T=KCTC 92884T) represents a type of novel species and genus for which we propose the name Marinimicrococcus gen. nov., sp. nov.

A Gram-stain-negative, strictly aerobic and filamentous bacterial strain, designated as DQS-5T, was isolated from the activated sludge of a municipal sewage treatment plant in Shenzhen, PR China. Optimal growth was observed at 28 °C and pH 7.5. Catalase and oxidase activities were detected. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain DQS-5T was most closely related to the genera Chitinimonas and Chitinivorax (91.0–93.4 % and 92.5 % 16S rRNA gene sequence similarity, respectively) and was close to the member of the family Burkholderiaceae . The complete genome sequence of strain DQS-5T contains 5 653 844 bp and 57.3 mol% G+C. The average nucleotide identity, digital DNA–DNA hybridization and average amino acid identity values between the genome of strain DQS-5T and those of its close relatives were 75.9–77.2, 19.0–20.3 and 57.2–61.8 %, respectively. Chemotaxonomic analysis of strain DQS-5T indicated that the sole respiratory quinone was ubiquinone-8, the predominant cellular fatty acids were C16 : 0 and summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c), and the major polar lipids consisted of phosphatidylethanolamine, phosphatidylglycerol, aminophospholipid and aminolipid. The phylogenetic, genotypic, phenotypic and chemotaxonomic data demonstrate that strain DQS-5T represents a novel species in a novel genus within the family Burkholderiaceae , for which the name Parachitinimonas caeni gen. nov., sp. nov., is proposed. Strain DQS-5T (=KCTC 92788T=CCTCC AB 2022320T) is the type and only strain of P. caeni.

Three bacterial strains, namely LPB0304T, LPB0319T and LPB0142T, were isolated from coastal environments. The 16S rRNA gene sequences of the three isolates were found to show the highest sequence similarities to Massilia litorea (98.44 %), Marinobacter salinisoli (97.55 %) and Rhodobacter lacus (97.60 %), respectively. The low (<98.7 %) sequence similarities and tree topologies implied the novelty of the three isolates, representing novel genomic species of the genus Massilia , Marinobacter and Rhodobacter . Numerous biochemical and physiological features also supported the distinctiveness of the isolates from previously known species. Based on the phenotypic and phylogenetic data presented in this study, three novel species are suggested with the following names: Massilia litorea sp. nov. (LPB0304T=KACC 21523T=ATCC TSD-216T), Marinobacter salinisoli sp. nov. (LPB0319T=KACC 21522T=ATCC TSD-218T) and Rhodobacter xanthinilyticus sp. nov. (LPB0142T=KACC 18892T=JCM 31567T).

In this study, we report a Gram-stain-negative, rod-shaped, atrichous and aerobic bacterial strain named CSW1921T, which was isolated from the deep-sea water of a cold seep in South China Sea. Growth of strain CSW1921T occurred at 10.0–35.0 °C (optimum, 30 °C), pH 5.0–10.0 (optimum, pH 8.0–9.0) and with 0–9.0 % (w/v) NaCl (optimum, 1.0–2.0 %). Phylogenetic tree analysis based on 16S rRNA gene sequence or the genomic sequence indicated that strain CSW1921T belonged to the family Rhodobacteraceae and was closely related to Rhodophyticola porphyridii MA-7-27T (97.5 % sequence similarity). Genomic analysis indicated that strain CSW1921T contains a circular chromosome of 3 592 879 bp with G+C content of 60.5 mol%. The predominant respiratory quinone of CSW1921T was ubiquinone-10. The polar lipids of CSW1921T contained phosphatidylglycerol, three unidentified aminolipids, two unidentified phospholipids and two unidentified lipids. The major fatty acids of strain CSW1921T contained C16 : 0, C18 : 1 ω7c 11-methyl and summed feature 8 (C18 : 1 ω7c). The average nucleotide identity, DNA–DNA hybridization and average amino acid identity values between strain CSW1921T and members of its related species were 68.02–69.08 %, 12.7–12.9 % and 46.87–48.08 %, respectively, which were lower than the recommended threshold values for bacterial species or genus delineation. Phylogenetic, physiological, biochemical and morphological analyses suggested that strain CSW1921T represents a novel genus and a novel species of the family Rhodobacteraceae , and the name Fontisubflavum oceani gen. nov., sp. nov. is proposed with the type strain CSW1921T (=MCCC 1K08371T=KCTC 92834T).

Three Gram-stain-negative, aerobic and rod-shaped bacterial strains, designated RD2P54T, M1R5S18T and M1R5S59T, were isolated from a root and rhizosphere soil of Kalidium cuspidatum, in Baotou, PR China. The three strains showed 94.1–98.7 % 16S rRNA gene sequence similarities to   Luteimonas   strains, indicating they belonged to the genus   Luteimonas  . The phylogenomic tree based on core genomes showed that strain RD2P54T tightly clustered with   Luteimonas salinisoli   SJ-92T, while strains M1R5S18T and M1R5S59T clustered with each other and with Luteimonas viscosa XBU10T and   Luteimonas saliphila   SJ-9T. Though strains M1R5S18T and M1R5S59T showed high 16S rRNA similarity (99.4 %) to each other, the low average nucleotide identity based on blast (ANIb; 88.6 %) and digital DNA–DNA hybridization (dDDH; 31.6 %) values between them indicated that they belonged to two different species. The ANIb and dDDH values of strains RD2P54T, M1R5S18T and M1R5S59T with their closely neighbours are well below the delineation threshold values for identifying strains as representing different species. All three strains take iso-C15 : 0 and summed feature 9 (C16 : 0 10-methyl and/or iso-C17 : 1  ω9c) as major fatty acids, and ubiquinone-8 as the sole respiratory quinone. The major polar lipids of all three strains are diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. Based on phenotypic and phylogenetic data, these three strains should be considered to represent three novel species of the genus   Luteimonas  , for which the names Luteimonas endophytica sp. nov. (type strain RD2P54T=CGMCC 1.61535T =KCTC 92470T), Luteimonas rhizosphaericola sp. nov. (type strain M1R5S18T=CGMCC 1.61537T =KCTC 92469T) and Luteimonas kalidii sp. nov. (type strain M1R5S59T=CGMCC 1.61536T =KCTC 92471T) are proposed.

Five isolates of a xerophilic Talaromyces species were obtained from honey in Japan. Molecular phylogenetic analysis based on a combined dataset for four regions (rRNA internal transcribed spacer, β-tubulin, calmodulin and RNA polymerase II second largest subunit) revealed that the strains formed an independent clade in section Trachyspermi, which is sister to Talaromyces affinitatimellis, Talaromyces basipetosporus and Talaromyces speluncarum. The strains and their relatives have different growth on creatine agar, yeast extract sucrose agar and dichloran 18 % glycerol agar, different branching patterns (mostly monoverticillate or biverticillate, less frequently divaricate or terverticillate), and different sizes and surface structures of conidia. Xerotolerance tests were also conducted using media adjusted to five different sucrose concentrations (0, 20, 40, 60 and 80 %). The colony diameters of the strains were larger than those of T. affinitatimellis, T. basipetosporus and T. speluncarum at each sucrose concentration. Altogether, the obtained morphological, molecular and physiological data allowed the proposal of Talaromyces mellisjaponici sp. nov. for this novel species, with NBRC 116048T as the type strain.