Zong-Jun Du

Draconibacterium orientale gen. nov., sp. nov., isolated from two distinct marine environments, and proposal of Draconibacteriaceae fam. nov.

The taxonomic characteristics of two bacterial strains, FH5T and SS4, isolated from enrichment cultures obtained from two distinct marine environments, were determined. These bacteria were Gram-stain-negative, facultatively anaerobic rods. Growth occurred at 20-40 °C (optimum, 28-32 °C), pH 5.5-9.0 (optimum, pH 7.0-7.5) and in the presence of 1-7% NaCl (optimum, 2-4%). The major cellular fatty acids were anteiso-C15:0 and iso-C15:0. Menaquinone 7 (MK-7) was the sole respiratory quinone. The major polar lipids were phosphatidylethanolamine, an unkown phospholipid and an unknown lipid. The DNA G+C contents of strains FH5T and SS4 were both determined to be 42.0 mol%. The results of DNA-DNA hybridization studies indicated that the FH5T and SS4 genomes share greater than 95% relatedness. The strains formed a distinct phyletic line within the class Bacteroidia, with less than 89.4% sequence similarity to their closest relatives with validly published names. On the basis of physiological and biochemical characteristics, 16S rRNA gene sequences and chemical properties, a novel genus and species, Draconibacterium orientale gen. nov., sp. nov., within the class Bacteroidia, are proposed, with strain FH5T (=DSM 25947T=CICC 10585T) as the type strain. In addition, a new family, Draconibacteriaceae fam. nov., is proposed to accommodate Draconibacterium gen. nov.

Saccharicrinis carchari sp. nov., isolated from a shark, and emended descriptions of the genus Saccharicrinis and Saccharicrinis fermentans.

A Gram-stain-negative, facultatively anaerobic, gliding, yellow-pigmented bacterium, designated SS12(T), was isolated from shark gill homogenate and characterized using a polyphasic approach. The strain was catalase-positive and oxidase-negative. Optimal growth occurred at 28-30 °C, pH 7.0-7.5 and in the presence of 2-4% (w/v) NaCl. The DNA G+C content was 40.0 mol%. The strain contained MK-7 as the prevailing menaquinone; iso-C15 : 0 and anteiso-C15 : 0 as the major cellular fatty acids; and phosphatidylethanolamine and an unknown lipid as the predominant polar lipids. Comparative analysis of 16S rRNA gene sequences demonstrated that the novel isolate showed the highest sequence similarity (94.68%) to Saccharicrinis fermentans DSM 9555(T) and the sequence similarities among the type strains of all other species studied were less than 92%. A phylogenetic tree, based on 16S rRNA gene sequences, showed that strain SS12(T) and Saccharicrinis fermentans DSM 9555(T) formed a distinct cluster within the family Marinilabiliaceae. On the basis of its phylogenetic position and phenotypic traits, strain SS12(T) represents a novel species of genus Saccharicrinis, for which the name Saccharicrinis carchari sp. nov. is proposed. The type strain is SS12(T) ( = CICC 10590(T) = DSM 27040(T)). Emended descriptions of the genus Saccharicrinis and Saccharicrinis fermentans are also provided.

Agarivorans gilvus sp. nov. isolated from seaweed.

A novel agarase-producing, non-endospore-forming marine bacterium, WH0801(T), was isolated from a fresh seaweed sample collected from the coast of Weihai, China. Preliminary characterization based on 16S rRNA gene sequence analysis showed that WH0801(T) shared 96.1  % similarity with Agarivorans albus MKT 106(T), the type species of the genus Agarivorans. A polyphasic taxonomic study was conducted and confirmed the phylogenetic affiliation of strain WH0801(T) to the genus Agarivorans. Isolate WH0801(T) produces light-yellow-pigmented colonies; cells are Gram-stain-negative, straight or curved rods, which are motile with a single polar flagellum. Strain WH0801(T) grew in 0.5-5  % NaCl, with optimum growth at 3  % NaCl, and its optimal pH and cultivation temperature were 8.4-8.6 and 28-32 °C, respectively. Data from biochemical tests, whole-cell fatty acid profiling, 16S rRNA gene sequence studies and DNA-DNA hybridization clearly indicated that isolate WH0801(T) represented a novel species within the genus Agarivorans, for which the name Agarivorans gilvus sp. nov. is proposed. The type strain of Agarivorans gilvus sp. nov. is WH0801(T) (=NRRL B-59247(T) =CGMCC 1.10131(T)).

Tangfeifania diversioriginum gen. nov., sp. nov., a representative of the family Draconibacteriaceae.

A novel Gram-stain-negative, facultatively anaerobic, catalase- and oxidase-positive, non-motile and pink-pigmented bacterium, designated G22(T), was isolated from Gahai, a saltwater lake in Qinghai province, China. Optimal growth occurred at 33-35 °C, pH 7.0-7.5, and in the presence of 2-4% (w/v) NaCl. The DNA G+C content was 40.0 mol%. The major polar lipids were phosphatidylethanolamine and three unknown lipids. The predominant cellular fatty acids were iso-C15:0, anteiso-C15:0, iso-C17:0 3-OH and iso-C15:0 3-OH, and MK-7 was the main respiratory quinone. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain G22(T) fell within the class Bacteroidia. Its closest phylogenetic neighbour was the recently described species Draconibacterium orientale, the sole member of the family Draconibacteriaceae, with merely 90.04% sequence similarity. On the basis of phenotypic, chemotaxonomic and phylogenetic evidence observed, a novel species in a new genus, Tangfeifania diversioriginum gen. nov., sp. nov., is proposed within the family Draconibacteriaceae. The type strain is G22(T) ( = CICC 10587(T) =DSM 27063(T)).

Aquimarina agarivorans sp. nov., a genome-sequenced member of the class Flavobacteriia isolated from Gelidium amansii.

A novel Gram-stain-negative, facultatively anaerobic, rod-shaped, agar-digesting bacterial strain, designated HQM9T, was isolated from the surface of the marine red alga Gelidium amansii collected from the intertidal zone of Weihai, China. Cells of HQM9T were 3.0-4.0 μm long and 0.2-0.3 μm wide and lacked flagella. The new isolate grew optimally at 28-30 °C, at pH 7.0-7.5, and in the presence of 2.5-3.0% NaCl. The predominant cellular fatty acids were iso-C15 : 0 and iso-C17 : 0 3-OH. The sole menaquinone was MK-6. The DNA G+C content was 33 mol%. The major polar lipids were comprised of phosphatidylethanolamine and four unknown polar lipids. Based on the 16S rRNA gene sequence, the closest relative was Aquimarina agarilytica ZC1T with 97.16% sequence similarity, with which strain HQM9T formed a distinct cluster belonging to the genus Aquimarina in a phylogenetic tree. Moreover, average nucleotide identity and estimated DNA-DNA hybridization values between strains HQM9T and ZC1T were 78.7% and 12.50 ± 2.95%, respectively. On the basis of phenotypic, chemotaxonomic and phylogenetic analysis, strain HQM9T represents the type strain of a novel species within the genus Aquimarina in the family Flavobacteriaceae, phylum Bacteroidetes, for which the name Aquimarina agarivorans sp. nov. is proposed. The type strain is HQM9T ( = ATCC BAA-2612T = CICC 10835T).

Woeseia oceani gen. nov., sp. nov., a chemoheterotrophic member of the order Chromatiales, and proposal of Woeseiaceae fam. nov.

A novel Gram-stain-negative, rods or bent rods, facultatively anaerobic, oxidase-negative and catalase-positive bacterium, designated XK5T, was isolated from coastal sediment from Xiaoshi Island, Weihai, China. Optimal growth occurred at 28-35 °C (range 8-42 °C) and pH 7.0-8.0 (range pH 6.0-9.0) with 1-3 % (w/v) NaCl (range 0.5-8 %). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain XK5T was 92.1 % similar to the type strain of Thioalkalivibrio thiocyanodenitrificans, 91.9 % to the type strain of Thioalkalivibrio sulfidiphilus and 91.8 % to the type strain of Thioalkalivibrio denitrificans; similarity to other species was less than 91 %. The isolate and closely related environmental clones formed a novel family level clade in the order Chromatiales. The polar lipid profile of the novel isolate consisted of phosphatidylethanolamine, phosphatidylglycerol and some other unknown phospholipids, aminolipids and lipids. Major cellular fatty acids were iso-C17 : 1ω9c and iso-C15 : 0 and the main respiratory lipoquinone was Q-8. The DNA G+C content of strain XK5T was 59.3 mol%. Comparative analysis of 16S rRNA gene sequences and characterization indicated that strain XK5T represents a novel species of a new genus within a novel family of the order Chromatiales, for which the name Woeseia oceani gen. nov., sp. nov. is proposed. The type strain of Woeseia oceani is XK5T ( = ATCC BAA-2615T = CICC 10905T). In addition, a novel family name, Woeseiaceae fam. nov., is proposed to accommodate the genus Woeseia.

Description of Ancylomarina subtilis gen. nov., sp. nov., isolated from coastal sediment, proposal of Marinilabiliales ord. nov. and transfer of Marinilabiliaceae, Prolixibacteraceae and Marinifilaceae to the order Marinilabiliales.

A Gram-stain-negative, facultatively anaerobic, moderately halophilic, filamentous, non-motile bacterium, designated FA102T, was isolated from marine sediment from the coast of Weihai, PR China. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain FA102T formed a distinct evolutionary lineage within the family Marinifilaceae and its closest relative was Marinifilum fragile JCM 15579T (93.2 % sequence similarity). The DNA G+C content of the novel strain was 36.5 mol%. The predominant cellular fatty acids and respiratory quinone were iso-C15 : 0 and iso-C15 : 0 3-OH, and MK-7, respectively. On the basis of the phylogenetic, phenotypic and physiological data, strain FA102T represents a novel genus and species, for which the name Ancylomarina subtilis gen. nov., sp. nov. is proposed. The type strain of Ancylomarina subtilis is FA102T (=KCTC 42257T=DSM 28825T=CICC 10902T). Furthermore, a new order named Marinilabiliales is proposed to accommodate three families previously classified in the order Bacteroidales. Marinilabiliales ord. nov. encompasses the families Marinilabiliaceae, Prolixibacteraceae and Marinifilaceae.

Longimonas halophila gen. nov., sp. nov., isolated from a marine solar saltern.

A bacterial strain, designated SYD6(T), was isolated from a marine solar saltern on the coast of Weihai, Shandong Province, PR China. Cells of strain SYD6(T) were rod-shaped, red, and approximately 5.0-9.0 μm in length and 0.4-0.6 μm in width. The strain was Gram-stain-negative, facultatively anaerobic, heterotrophic, catalase-positive and oxidase-negative. Growth occurred in 4-25% (w/v) NaCl [with 2-15% (w/v) MgCl2.6H2O also present], at 20-50 °C and pH 6.5-8.5. Optimal growth was observed at 37-42 °C, pH 7.5-8.0, with 6-8% (w/v) NaCl [with 2-4% (w/v) MgCl2.6H2O]. Nitrate was not reduced. Glucose, sucrose, maltose, fructose and ribose stimulated growth, but not glycerol, xylose or mannitol. The G+C content of the genomic DNA was 61.5 mol% (HPLC). The sole methyl naphthoquinone was MK-7 and the predominant cellular fatty acids (>10%) were iso-C15 : 0 2-OH/C16 : 1ω7c, iso-C16 : 0, C18 : 1ω7c/C18 : 1ω6c and C18 : 1ω7c. The predominant polar lipids were phosphatidylethanolamine, phosphatidylcholine, diphosphatidylglycerol and an unknown lipid. Phylogenetic analysis, based on 16S rRNA gene sequences, demonstrated that strain SYD6(T) was affiliated with the phylum Bacteroidetes. The most closely related neighbours were species of the genus Salisaeta and strain SYD6(T) had a 16S rRNA gene sequence similarity of 91.97% with Salisaeta longa DSM 21114(T). On the basis of these phenotypic and phylogenetic data, strain SYD6(T) represents a novel species of a new genus of the family Rhodothermaceae, for which the name Longimonas halophila gen. nov., sp. nov. is proposed. The type strain of the type species is SYD6(T) ( = CICC 10838(T) = KCTC 42399(T)).

Marinifilum albidiflavum sp. nov., isolated from coastal sediment

A novel Gram-stain-negative, facultatively anaerobic, filamentous, and yellowish-white-pigmented marine bacterium, designated strain FB208T, was isolated from marine sediment obtained off the coastal area of Weihai, China. Cells of strain FB208T were filamentous during exponential growth, fragmented to rods in the stationary growth phase and became spherical in aged cultures. It grew optimally at 33 °C, at pH 7.0-7.5 and in the presence of 2.0-3.0 % (w/v) NaCl. Based on the 16S rRNA gene sequence, strain FB208T was found to be closely related to Marinifilum flexuosum DSM 21950T (96.9 % similarity) and Marinifilum fragile JCM 15579T (96.4 %), with less than 90.0 % sequence similarity to other genera of the class Bacteroidia. Phylogenetic analysis, also based on 16S rRNA gene sequences, placed strain FB208T in the genus Marinifilum, family Marinifilaceae. The predominant isoprenoid quinone of strain FB208T was identified as menaquinone MK-7. The main cellular fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH and iso-C17 : 1ω9c, and the major polar lipids were an unidentified lipid and aminophospholipid. The G+C content of the genomic DNA was 43.8 mol%. Based on these phylogenetic and phenotypic data, strain FB208T represents a novel species of the genus Marinifilum, for which the name Marinifilum albidiflavum sp. nov. is proposed. The type strain is FB208T (=KCTC 42591T=MCCC 1H00113T).

Draft Genome Sequence of the Novel Agar-Digesting Marine Bacterium HQM9

Strain HQM9, an aerobic, rod-shaped marine bacterium from red algae, can produce agarases and liquefy solid plating media efficiently when agar is used as a coagulant. Here we report the draft genome sequence and the initial findings from a preliminary analysis of strain HQM9, which should be a novel species of Flavobacteriaceae.