Atopomonas sediminilitoris sp. nov., isolated from beach sediment of Zhairuo Island, China.

A novel bacterium designated A3.4T was isolated from the beach sediment of Zhairuo Island, which is located in the East China Sea. Strain A3.4T was found to be Gram-stain negative, cream coloured, rod-shaped, aerobic and motile via a single monopolar flagellum. The isolate grows at 20-37 °C (optimum 25-30 °C), at pH 6.0-8.0 (optimum pH 7.0-8.0), and in the presence of 0-5.0% (w/v) NaCl (optimum 0.5-1%). A3.4T has catalase and oxidase activity. The predominant fatty acids (≥ 10%) of the strain were identified as C16:0, summed feature 3 (C16:1 ω7c /C16:1 ω6c) and summed feature 8 (C18:1 ω7c /C18:1 ω6c). Q-9 was identified as the major isoprenoid quinone, with trace levels of Q-8 present. The major polar lipids were identified as diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The draft genome size is 3.55 Mb, with a DNA G + C content of 57.7 mol%. Analysis of the 16S rRNA gene sequence of strain A3.4T indicates that it belongs to the genus Atopomonas and shares high sequence similarity with Atopomonas hussainii JCM 19513T (97.60%). This classification was also supported by phylogenetic analysis using rpoB and several core genes. The genome of strain A3.4T shows an average nucleotide identity of 82.3%, an amino acid identity of 83.0%, and a digital DNA-DNA hybridization value of 22.1% with A. hussainii. In addition, 20 conserved signature indels (CSIs) were identified to be specific for A3.4T and A. hussainii, demonstrating that the strain A3.4T is closely related to A. hussainii rather than other species of family Pseudomonadaceae. Hundreds of unique genes were identified in the genomes of A3.4T and A. hussainii, which may underly multiple phenotypic differences between these strains. Based on phenotypic, chemotaxonomic, phylogenetic, and genomic investigations, strain A3.4T is concluded to represent a novel species of the genus Atopomonas, for which the name Atopomonas sediminilitoris sp. nov. is proposed. The type strain is A3.4T (= LMG 32563T = MCCC 1K07166T).

Ancylobacter gelatini sp. nov., isolated from beach sediment of Zhairuo Island, China.

A Gram-negative, aerobic, non-motile, oxidase-positive, catalase-positive, methyl red-positive, and lipase-negative bacterium, designated A5.8T, was isolated from beach sediment of Zhairuo Island located in the East China Sea. Growth occurred at 10-40 °C (optimum, 30 °C), pH 5.5-9.5 (optimum, 7.5), and 0-2% NaCl (optimum, 1.5%). Based on 16S rRNA gene sequence analysis, strain A5.8T belongs to the genus Ancylobacter, sharing the highest similarity with Ancylobacter aquaticus JCM 20518T (98.0%). Its polar lipids mainly consist of phosphatidylethanolamine (PE) and phosphatidylcholine (PC). The predominant fatty acids are summed feature 8 (C18:1ω7c and/or C18:1ω6c, 91.0%), and the major respiratory quinone is Q-10. The DNA G + C content is 67.2 mol%. Based on above analysis, as well as digital DNA-DNA hybridization (22.5-22.9%) and average nucleotide identity (83.0-83.6%) of strain A5.8T with reference type strains of the genus Ancylobacter, strain A5.8T was suggested to represent a novel species of the genus Ancylobacter, for which the name Ancylobacter gelatini sp. nov. is proposed. The type strain is A5.8T (= MCCC 1K07167T = LMG 32566T).

Acinetobacter sedimenti sp. nov., isolated from beach sediment.

A Gram-stain-negative, aerobic, non-motile, non-haemolytic, oxidase-negative, catalase-positive bacillus strain (A3.8T) was isolated from beach sediment from Zhairuo Island, PR China. The strain grew at pH 6.0-9.0 (optimum, 7.0), with 0-4.5 % NaCl (optimum, 2 %) and at 10-35 °C (optimum, 30 °C). Its whole-genome sequence was 2.5 Mb in size, with a DNA G+C content of 41.6 mol%. On the basis of the results of core genome phylogenetic analysis, A3.8T represents a separate branch within the clade formed by five species of the genus Acinetobacter with 'Acinetobacter marinus' as the most closely related species. The average nucleotide identity compared with the closely related species of the genus Acinetobacter was below 83.66 % and digital DNA-DNA hybridization values were less than 28.80 %. The predominant fatty acids included C18 : 1ω9c, C16 : 0 and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c). Q-9 was the major respiratory quinone. The polar lipids are mainly composed of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, two phospholipids, an aminolipid and four unknown lipids. A3.8T cannot assimilate dl-lactate and weakly utilizes l-glutamate, l-leucine, l-phenylalanine and l-tartrate, which distinguishes it from other species of the genus Acinetobacter. On the basis of the genotype, phenotype and biochemical data, strain A3.8T represents a novel species of the genus Acinetobacter, for which the name Acinetobacter sedimenti sp. nov. is proposed. The type strain is A3.8T (=MCCC 1K07161T=LMG 32568T).

Flavobacterium salilacus sp. nov., isolated from surface water of a hypersaline lake, and descriptions of Flavobacterium salilacus subsp. altitudinum subsp. nov. and Flavobacterium salilacus subsp. salilacus subsp. nov.

Two yellow-pigmented, Gram-stain-negative, aerobic, rod-shaped bacteria were isolated from the water of the hypersaline Chaka Salt Lake (strain SaA2.12T) and sediment of Qinghai Lake (strain LaA7.5T), PR China. According to the 16S rRNA phylogeny, the isolates belong to the genus Flavobacterium, showing the highest 16S rRNA sequence similarities to Flavobacterium arcticum SM1502T(97.6-97.7 %) and Flavobacterium suzhouense XIN-1T(96.5-96.6 %). Moreover, strains SaA2.12T and LaA7.5T showed 99.73 % 16S rRNA sequence similarity to each other. Major fatty acids, respiratory quinones and polar lipids detected in these isolates were iso-C15 : 0, menaquinone-6 and phosphatidylethanolamine, respectively. Strains SaA2.12T and LaA7.5T showed significant unique characteristics between them as well as between the closest phylogenetic members. The highest digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) values between SaA2.12T and its closest neighbours were 25.3 and 82.8 %, respectively; whereas these values (highest) between LaA7.5T and its closest members were 25.2 and 82.8 %, respectively. The dDDH and ANI values between strains SaA2.12T and LaA7.5T were calculated as 75.9 and 97.2 %, respectively. Therefore, based on polyphasic data, we propose that strain SaA2.12T represents a novel species with the name Flavobacterium salilacus sp. nov., with the type strain SaA2.12T (=KCTC 72220T=MCCC 1K03618T) and strain LaA7.5T as a subspecies within novel Flavobacterium salilacus with the name Flavobacterium salilacus subsp. altitudinum subsp. nov., with the type strain LaA7.5T (=KCTC 72806T=MCCC 1K04372T). These propositions automatically create Flavobacterium salilacus subsp. salilacus subsp. nov. with SaA2.12T (=KCTC 72220T=MCCC 1K03618T) as the type strain.

Flavobacterium zhairuonensis sp. nov., a gliding bacterium isolated from marine sediment of the East China Sea.

A yellow pigmented, Gram-stain-negative, aerobic bacterium designated A5.7T was studied to evaluate the taxonomic position following the modern polyphasic approach. The strain was isolated from sediments near Zhairuo Island, which is situated in the East China Sea. Cells were non-spore forming rods without flagella but showed motility by gliding. Growth was observed at 15-35°C (optimum 28°C), pH 6.0-9.0 (optimum pH 6.5) and 0-2% (w/v) NaCl (optimum 0-0.5%) in LB broth. The major respiratory quinone of A5.7T was menaquinone 6. The major polar lipid of A5.7T was phosphatidylethanolamine and the predominant fatty acids (> 5%) were iso-C15:0, iso-C17:0 3-OH, C15:1ω6c, iso-C15:0 3-OH, iso-C15:1 G, summed feature 3 (C16:1ω7c and/or C16:1ω6c) and summed feature 9 (iso-C17:1ω9c and/or C16:010-methyl). Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolate belongs to the genus Flavobacterium and shares the highest sequence similarities with Flavobacterium sharifuzzamanii A7.6T (98.5%), Flavobacterium tistrianum GB 56.1T (98.3%), Flavobacterium nitrogenifigens NXU-44T (97.8%), Flavobacterium anhuiense D3T (97.6%), Flavobacterium ginsenosidimutans THG 01T (97.6%), and Flavobacterium foetidum CJ42T (97.6%). Digital DNA-DNA hybridization and average nucleotide identity values between the strain and its closest phylogenetic neighbors showed the ranges from 19.6 to 34.1% and 73.7 to 87.9%, respectively. Therefore, based on polyphasic characteristics, strain A5.7T represents a novel species of the genus Flavobacterium for which the name Flavobacterium zhairuonensis sp. nov. is proposed. The type strain is A5.7T (= KCTC 62406T = MCCC 1K03494T).