Meridianimarinicoccus roseus gen. nov., sp. nov., a novel genus of the family Rhodobacteraceae isolated from seawater

Limibaculum sediminis sp. nov., isolated from mangrove sediment

A Gram-stain-negative, cream-coloured, aerobic, motile and ovoid- to rod-shaped bacterium, designated as FT325^T, was isolated from mangrove sediment collected in Shenzhen, PR China. The taxonomic position of strain FT325^T was established by phylogenetic, physiological, biochemical and chemotaxonomic analyses. Strain FT325^T grew optimally at 37-40 °C and pH 6.0 in the presence of 0 % (w/v) NaCl. Results of 16S rRNA gene sequence analysis showed that strain FT325^T was most similarly related to Limibaculum halophilum CAU 1123^T (96.2 %), Phaeovulum vinaykumarii DSM 18714^T (93.9%) and Amaricoccus solimangrovi HB 172011^T (93.7 %). The major fatty acids (>10 %) were C_18 : 1  ω7c (60.0 %) and 11-methyl C_18 : 1  ω7c (16.7 %). The sole respiratory quinone was Q-10. The polar lipids were phosphatidylglycerol, one unidentified glycolipid, three unidentified aminolipids and three unidentified phospholipids. Its estimated genome size was 4 318 768 bp and the genomic DNA G+C content was 69.6 mol%. Based on its distinct phenotypic, chemotaxonomic and phylogenetic characteristics, strain FT325^T represents a novel species of the genus Limibaculum, for which the name Limibaculum sediminis sp. nov. is proposed (=MCCC 1K07397^T=KCTC 92313^T).

Nocardioides malaquae sp. nov., a novel actinobacterium isolated from sewage sludge of a fisheries processing factory

A Gram-stain-positive, rod-shaped, strictly aerobic bacterial strain (Y6^T) was isolated from a sewage sludge sample collected from a fisheries processing factory in Zhoushan, Zhejiang Province, PR China. The growth range of NaCl concentration was 0-6.0 % (w/v), with an optimum at 3.0 % (w/v). The temperature range for growth was 10-42 °C, with an optimum at 37 °C. The pH range for growth was pH 7.0-10.0, with an optimum at pH 9.0. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain Y6^T belonged to the genus Nocardioides and showed the highest sequence similarity of 97.8 % to Nocardioides jishulii dk3136^T. The average nucleotide identity and in silico DNA-DNA hybridization values between strain Y6^T and the reference strains were 76.9-81.2 % and 20.6-23.6 %, respectively. Chemotaxonomic analysis indicated that the sole respiratory quinone was MK-8(H₄) and the predominant cellular fatty acids were iso-C_16 : 0, 10-methyl-C_17 : 0 and C_18 : 1  ω9c. The polar lipid profile was composed of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, four unidentified phospholipids, three unidentified aminolipids and five unidentified lipids. The peptidoglycan was ll-2,6-diaminopimelic acid. On the basis of the phenotypic, genotypic, phylogenetic and chemotaxonomic features, strain Y6^T is considered to represent a novel species, for which the name Nocardioides malaquae sp. nov. is proposed. The type strain is Y6^T (=KCTC 49504^T=MCCC 1K04765^T).

Qingshengfaniella alkalisoli gen. nov., sp. nov., a p-hydroxybenzoate-degrading strain isolated from saline soil

p-Hydroxybenzoate is an allelopathic compound commonly found in soil from long-term monoculture cropping systems. During the bacterial diversity analysis of saline soil, a Gram-negative, non-spore forming, non-motile, aerobic p-hydroxybenzoate-degrading bacterial strain, designated LN3S51^T, was isolated from saline soil which was sampled from Tumd Right Banner, Inner Mongolia, northern China. Strain LN3S51^T grew at 4-40 °C (optimum, 30 °C), pH 5.0-10.0 (optimum, pH 7.0) and 0-15 % NaCl (optimum 3.0 %). Though strain LN3S51^T has the highest 16S rRNA gene similarities to Litoreibacter ponti GJSW-31^T (96.0 %), the phylogenetic tree based on the 16S rRNA gene sequences showed that it clustered with Fluviibacterium aquatile SM1902^T (95.8 %), Meridianimarinicoccus roseus TG-679^T (93.9 %), and Phycocomes zhengii LMIT002^T (93.9 %). Strain LN3S51^T contained Q-10 as the major ubiquinone. Phosphatidylethanolamine (PE), phosphatidylglycerol (PG), phosphatidylcholine (PC), diphosphatidylglycerol (DPG), an unidentified aminolipid (AL), and two unidentified lipids (L) were the major polar lipids. The major fatty acids were sum feature 8 (C_18 : 1  ω7c and/or C_18 : 1  ω6c), C_16 : 0, C_18 : 0, and C_18 : 1  ω7c 11-methyl. The genome of strain LN3S51^T consisted of a 2 257 066 bp chromosome and four plasmids with a 59.1 mol% of genomic DNA G+C content. The average nucleotide identity (ANI) and digital DNA-DNA hybridization score (dDDH) values of strain LN3S51^T to F. aquatile SM1902^T, M. roseus TG-679^T, P. zhengii LMIT002^T, and L. ponti GJSW-31^T were 69.6, 70.9, 70.6, and 69.5 %, and 20.0, 19.5, 19.0, and 20.0 %, respectively. Based on the results of phylogenetic, chemtaxonomic and phenotypic characterization, strain LN3S51^T is considered to represent a novel species in a new genus within the family Rhodobacteraceae, for which Qingshengfaniella alkalisoli gen. nov., sp. nov. is proposed. The type strain is LN3S51^T (=CGMCC 1.17099^T=KCTC 72457^T).

Oceanomicrobium pacificus gen. nov., sp. nov., a member of the family Rhodobacteraceae isolated from seawater of tropical western Pacific

The Gram-stain-negative, aerobic, ovoid or rod-shaped bacterial strain, designated KN286^T, was isolated from seawater of tropical western Pacific. Growth occurred between 15 and 40 °C (optimally at 30-35 °C), pH 6-9 (optimally at 7.0) and in the presence of 0.5-5.0% (w/v) NaCl (optimally between 2.0 and 3.0%). Strain KN286^T contained Q-10 as the major respiratory quinone. The polar lipid profile contained phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, three phospholipids, three glycolipids, and three unidentified polar lipids. The predominant cellular fatty acid was summed feature 8 (composed of C_18:1ω7c and/or C_18:1ω6c). Phylogenetic analysis of the 16S rRNA gene sequence revealed that strain KN286^T was a member of the family Rhodobacteraceae and formed a distinct lineage. Strain KN286^T has a genome size of 3.25 Mbp and a G + C content of 65.0 mol%. It encoded with some genes for carbohydrate-active enzymes, such as GH20 (Glycoside Hydrolase Family 20) and PL1 (Polysaccharide Lyase Family 1) and did not encode with a set of genes for reduction of nitrate to nitrite (nitrate reductase gamma subunit, respiratory nitrate reductase alpha N-terminal and respiratory nitrate reductase beta C-terminal). Based on phylogenetic analyses with single-copy orthologous clusters, low isDDH value (19.6%), low ANI (72.4%) and low AAI (65.7%) results, differential chemotaxonomic and physiological properties, strain KN286^T represents a novel species of a novel genus of the family Rhodobacteraceae, for which the name Oceanomicrobium pacificus gen. nov., sp. nov. is proposed. The type strain of Oceanomicrobium pacificus is KN286^T (=CGMCC 1.17118^T = KCTC 72430^T).

Physiological and genomic features of Paraoceanicella profunda gen. nov., sp. nov., a novel piezophile isolated from deep seawater of the Mariana Trench

A novel piezophilic alphaproteobacterium, strain D4M1^T, was isolated from deep seawater of the Mariana Trench. 16S rRNA gene analysis showed that strain D4M1^T was most closely related to Oceanicella actignis PRQ‐67^T (94.2%), Oceanibium sediminis O448^T (94.2%), and Thioclava electrotropha ElOx9^T (94.1%). Phylogenetic analyses based on both 16S rRNA gene and genome sequences showed that strain D4M1^T formed an independent monophyletic branch paralleled with the genus Oceanicella in the family Rhodobacteraceae. Cells were Gram‐stain‐negative, aerobic short rods, and grew optimally at 37°C, pH 6.5, and 3.0% (w/v) NaCl. Strain D4M1^T was piezophilic with the optimum pressure of 10 MPa. The principal fatty acids were C_18:1ω7c/C_18:1ω6c and C_16:0, major respiratory quinone was ubiquinone‐10, and predominant polar lipids were phosphatidylglycerol, phosphatidylethanolamine, and an unidentified aminophospholipid. The complete genome contained 5,468,583‐bp with a G + C content of 70.2 mol% and contained 4,855 protein‐coding genes and 78 RNA genes. Genomic analysis revealed abundant clues on bacterial high‐pressure adaptation and piezophilic lifestyle. The combined evidence shows that strain D4M1^T represents a novel species of a novel genus in the family Rhodobacteraceae, for which the name Paraoceanicella profunda gen. nov., sp. nov. is proposed (type strain D4M1^T = MCCC 1K03820^T = KCTC 72285^T).