Marinobacter changyiensis, sp. nov., isolated from offshore sediment

An aerobic, Gram-stain-negative bacterium, designated CLL7-20^T, was isolated from a marine sediment sample from offshore of Changyi, Shandong Province, China. Cells of strain CLL7-20^T were rod-shaped, motile with one or more polar flagella, and grew optimally at pH 7.0, at 28 °C and with 3 % (w/v) NaCl. The principal fatty acids of strain CLL7-20^T were C_16 : 0 and summed feature 3 (C_16 : 1 ω7c/C_16 : 1 ω6c). The main polar lipids of strain CLL7-20^T were phosphatidylethanolamine (PE), phosphatidylglycerol (PG), diphosphatidylglycerol (DPG) and an unidentified aminolipid (AL). Strain CLL7-20^T contained Q-9 as the major respiratory quinone. The G+C content of its genomic DNA was 56.2 mol%. Phylogenetically, strain CLL7-20^T branched within the genus Marinobacter, with M. daqiaonensis YCSA40^T being its closest phylogenetic relative (96.7 % 16S rRNA gene sequence similarity), followed by M. sediminum R65^T (96.6 %). Average nucleotide identity and in silico DNA-DNA hybridization values between strain CLL7-20^T and the closest related reference strains were 73.2% and 19.8 %, respectively. On the basis of its phenotypic, phylogenetic and chemotaxonomic characteristics, we suggest that strain CLL7-20^T (=MCCC 1A14855^T=KCTC 72664^T) is the type strain of a novel species in the genus Marinobacter, for which the name Marinobacter changyiensis sp. nov. is proposed. Based on the genomic analysis, siderophore genes were found from strain CLL7-20^T, which indicate its potential as a promising alternative to chemical fertilizers in iron-limitated environments such as saline soils.

Marinobacter profundi sp. nov., a slightly halophilic bacterium isolated from a deep-sea sediment sample of the New Britain Trench

A piezotolerant, cold-adapted, slightly halophilic bacterium, designated strain PWS21^T, was isolated from a deep-sea sediment sample collected from the New Britain Trench. Cells were observed to be Gram-stain negative, rod-shaped, oxidase- and catalase-positive. Growth of the strain was observed at 4-45 °C (optimum 37 °C), at pH 5.0-9.0 (optimum 7.0) and in 0.5-20% (w/v) NaCl (optimum 3-4%). The optimum pressure for growth was 0.1 MPa (megapascal) with tolerance up to 70 MPa. 16S rRNA gene sequence analysis showed that strain PWS21^T is closely related to Marinobacter guineae M3B^T (98.4%) and Marinobacter lipolyticus SM19^T (98.2%). Multilocus sequence analysis (MLSA) based on sequences of housekeeping genes gyrB, recA, atpD, rpoB and rpoD indicates that strain PWS21^T represents a distinct evolutionary lineage within the genus Marinobacter. Furthermore, strain PWS21^T showed low ANI and diDDH values to the closely related species. The principal fatty acids were identified as C_12:0, C_12:0 3-OH, C_16:1ω9c, C_16:0 and C_18:1ω9c. Ubiquinone-9 was identified as the major respiratory quinone. The polar lipids were identified as phosphatidylethanolamine (PE), phosphatidylglycerol (PG), diphosphatidylglycerol (DPG), aminophospholipid (APL), two unidentified lipids and an unidentified phospholipid (PL). The G + C content of the genomic DNA was determined to be 60.3 mol%. On the basis of phenotypic, chemotaxonomic and molecular data, we conclude that strain PWS21^T represents a novel species of the genus Marinobacter, for which the name Marinobacter profundi sp. nov. is proposed (type strain PWS21^T = KCTC 52990^T = MCCC 1K03345^T).

Polyphasic taxonomic characterisation of a novel strain as Pararhizobium haloflavum sp. nov., isolated from soil samples near a sewage treatment tank

A Gram-stain negative, aerobic, motile and ovoid- to rod-shaped bacteria strain, designated XC0140^T, was isolated from soil samples near the sewage treatment tank of a chemical factory in Zhejiang Province, China, and subjected to polyphasic taxonomic investigation. Strain XC0140^T grew at 10-37 °C and pH 6.0-9.0 (optimum, 35 °C and pH 7.5) and with 0-17% (w/v) NaCl (optimum, 1%). According to phylogenetic analysis based on 16S rRNA gene sequences, strain XC0140^T was assigned to the genus Pararhizobium with high 16S rRNA gene sequence similarity of 95.97% to "Pararhizobium helanshanense CCNWQTX14^T", followed by Pararhizobium sphaerophysae CCNWGS0238^T (95.95%). Chemotaxonomic analysis showed that strain XC0140^T contains ubiquinone-10 as the predominant respiratory quinone and possessed summed feature 8 (comprising C_{18: 1} ω7c and/or ω6c), 11-methyl C_18:1 ω7c, C_{18: 0} and C_{16: 0} as predominant forms of fatty acids. The polar lipids of strain XC0140^T consisted of seven phospholipids (PL), two aminolipids (AL), one glycolipid (GL) and three unidentified lipids (L1, L2 and L3). The DNA G+C content was 62.7 mol%. Based on the polyphasic taxonomic characterization, strain XC0140^T is considered to represent a novel species of the genus Pararhizobium, for which the name Pararhizobium haloflavum sp. nov. is proposed. (type strain XC0140^T = MCCC 1K03228^T = KCTC 52582^T).

Marinobacter nitratireducens sp. nov., a halophilic and lipolytic bacterium isolated from coastal surface sea water

A novel Gram-stain-negative, rod-shaped, motile bacterium, designated strain AK21T, was isolated from coastal surface sea water at Visakhapatnam, India. The strain was positive for oxidase, catalase, lipase, l-proline arylamidase and tyrosine arylamidase activities. The predominant fatty acids were C12:0, C12:0 3-OH, C16:0, C16:1ω9c, C18:1ω9c and summed feature 3 (C16:1ω7c and/or iso-C15:0 2-OH). The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, one unidentified aminophospholipid, two unidentified phospholipids and one unidentified lipid. Q-10 was the predominant respiratory quinone. The DNA G+C content of the strain was 54.6 mol%. 16S rRNA gene sequence analysis indicated that strain AK21T was a member of the genus Marinobacter and was closely related to Marinobacter xestospongiae, with pairwise sequence similarity of 97.2 % to the type strain, with similarity to other members of the genus of 94.0–96.8 %. The mean DNA–DNA relatedness of strain AK21T with M. xestospongiae JCM 17469T was 34.5 %, and relatedness with Marinobacter mobilis JCM 15154T was 40.5 %. Phylogenetic analysis showed that strain AK21T clustered with the type strains of M. xestospongiae and M. mobilis at distances of 2.9 and 2.8 % (97.1 and 97.2 % similarity), respectively. Based on the phenotypic characteristics and on phylogenetic inference, it appears that strain AK21T represents a novel species of the genus Marinobacter, for which the name Marinobacter nitratireducens sp. nov. is proposed. The type strain of Marinobacter nitratireducens is AK21T ( = MTCC 11704T = JCM 18428T).

Marinobacter halophilus sp. nov., a halophilic bacterium isolated from a salt lake

A Gram-staining-negative bacterium, strain XCD-X12(T), was isolated from Xiaochaidan Lake, a salt lake (salinity 9.9%, w/w) in Qaidam basin, Qinghai Province, China. Its taxonomic position was determined by using a polyphasic approach. Cells of strain XCD-X12(T) were non-spore-forming rods, 0.4-0.7 μm wide, 2.1-3.2 μm long and motile with a single polar flagellum. Strain XCD-X12(T) was strictly aerobic and catalase- and oxidase-positive. Growth was observed in the presence of 0-20.0% (w/v) NaCl (optimum, 4.0-8.0%), at 4-35 °C (optimum, 30 °C) and at pH 6.5-10.5 (optimum, pH 8.5). It contained Q-9 as the predominant respiratory quinone. The major fatty acids (>10.0%) were C16 : 0, C16 : 1ω9c and C18 : 1ω9c. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, two unknown phospholipids and an uncharacterized aminophospholipid. The DNA G+C content was 55.6 mol% (Tm). Phylogenetic trees based on 16S rRNA gene sequences showed that strain XCD-X12(T) was associated with the genus Marinobacter, and showed the highest 16S rRNA gene sequence similarity to Marinobacter hydrocarbonoclasticus ATCC 49840(T) (97.4%), M. vinifirmus FB1(T) (96.8%), M. excellens KMM 3809(T) (96.8%) and M. antarcticus ZS2-30(T) (96.7%). DNA-DNA relatedness of strain XCD-X12(T) to M. hydrocarbonoclasticus CGMCC 1.7683(T) was 34 ± 5%. Based on these data, it is concluded that strain XCD-X12(T) represents a novel species of the genus Marinobacter, for which the name Marinobacter halophilus sp. nov. is proposed. The type strain is XCD-X12(T) ( = CGMCC 1.12481(T)= JCM 30472(T)).

Marinobacter shengliensis sp. nov., a moderately halophilic bacterium isolated from oil-contaminated saline soil

Two moderately halophilic strains, designated SL013A34A2(T) and SL013A24A, were isolated from oil-contaminated saline soil from Shengli Oilfield, eastern China. Cells were found to be Gram-staining negative, aerobic, rod-shaped with a single polar flagellum. The isolates were found to grow at 10-40 °C (optimum 35 °C), pH 6.0-9.0 (optimum pH 8.0), and NaCl concentrations of 0.5-18.0 % (w/v) (optimum 3.0-6.0 NaCl). The 16S rRNA gene sequence analysis indicated that the isolates belong to the genus Marinobacter. Strain SL013A34A2(T) shares the highest 16S rRNA gene sequence similarities with strain SL013A24A (99.3 %), followed by M. hydrocarbonoclasticus CGMCC 1.7683(T) (97.8 %), M. vinifirmus CGMCC 1.7265(T) (97.8 %), and M. excellens KMM 3809(T) (97.4 %), respectively, but low similarities (93.8-96.4 %) with type strains of the other numbers of genus Marinobacter. DNA-DNA relatedness values of strain SL013A34A2(T) with strains SL013A24A, M. hydrocarbonoclasticus CGMCC 1.7683(T), M. vinifirmus CGMCC 1.7265(T) and M. excellens KMM 3809(T) were 88.7, 29.2, 33.4 and 29.4 %, respectively. The major fatty acids of strain SL013A34A2(T) were identified as C18:1 ω9c, C16:0, C12:03-OH, C12:0, C16:1 ω9c and 10-methyl C18:0. The major respiratory quinone of strain SL013A34A2(T) was found to be ubiquinone-9, and its predominant polar lipids were identified as diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol and unidentified glycolipid. The genomic DNA G + C content was found to be 56.1 mol %. Based on the phenotypic, genetic and chemotaxonomic characteristics, these two isolates are representatives of a novel species of the genus Marinobacter, for which the name Marinobacter shengliensis sp. nov. is proposed. The type strain is SL013A34A2(T)(=LMG 27740(T) = CGMCC 1.12758(T)).

Diversity of halophilic bacteria isolated from Rambla Salada, Murcia (Spain)

In this study we analyzed the diversity of the halophilic bacteria community from Rambla Salada during the years 2006 and 2007. We collected a total of 364 strains, which were then identified by means of phenotypic tests and by the hypervariable V1–V3 region of the 16S rRNA sequences (around 500 bp). The ribosomal data showed that the isolates belonged to Proteobacteria (72.5%), Firmicutes (25.8%), Actinobacteria (1.4%), and Bacteroidetes (0.3%) phyla, with Gammaproteobacteria the predominant class. Halomonas was the most abundant genus (41.2% isolates) followed by Marinobacter (12.9% isolates) and Bacillus (12.6% isolates). In addition, 9 strains showed <97% sequence identity with validly described species and may well represent new taxa. The diversity of the bacterial community analyzed with the DOTUR package determined 139 operational taxonomic units at 3% genetic distance level. Rarefaction curves and diversity indexes demonstrated that our collection of isolates adequately represented all the bacterial community at Rambla Salada that can be grown under the conditions used in this work. We found that the sampling season influenced the composition of the bacterial community, and bacterial diversity was higher in 2007; this fact could be related to lower salinity at this sampling time.

Characterization of microbial communities in heavy crude oil from Saudi Arabia

The complete mineralization of crude oil into carbon dioxide, water, inorganic compounds and cellular constituents can be carried out as part of a bioremediation strategy. This involves the transformation of complex organic contaminants into simpler organic compounds by microbial communities, mainly bacteria. A crude oil sample and an oil sludge sample were obtained from Saudi ARAMCO Oil Company and investigated to identify the microbial communities present using PCR-based culture-independent techniques. In total, analysis of 177 clones yielded 30 distinct bacterial sequences. Clone library analysis of the oil sample was found to contain Bacillus, Clostridia and Gammaproteobacteria species while the sludge sample revealed the presence of members of the Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Clostridia, Spingobacteria and Flavobacteria. The dominant bacterial class identified in oil and sludge samples was found to be Bacilli and Flavobacteria, respectively. Phylogenetic analysis showed that the dominant bacterium in the oil sample has the closest sequence identity to Enterococcus aquimarinus and the dominant bacterium in the sludge sample is most closely related to the uncultured Bacteroidetes bacterium designated AH.KK.

Halomonas zincidurans sp. nov., a heavy-metal-tolerant bacterium isolated from the deep-sea environment

A Gram-stain-negative, aerobic, rod-like, motile by peritrichous flagella and moderately halophilic bacterium, designated strain B6(T), was isolated a deep-sea sediment collected from the South Atlantic Ocean. The isolate grew with 0.5-15 % (w/v) NaCl, at 4-37 °C and pH 5.0-8.5 and showed a high tolerance to zinc, manganese, cobalt and copper ions. The major fatty acids were C16 : 0, C19 : 0 cyclo ω8c, C12 : 0 3-OH and C12 : 0. The predominant ubiquinone was Q-9. The genomic DNA G+C content was 61.1 mol%. Phylogenetic analysis based on 16S rRNA gene comparisons indicated that strain B6(T) belonged to the genus Halomonas, and the closest relative was Halomonas xinjiangensis TRM 0175(T) (96.1 %). Based upon the phenotypic, chemotaxonomic and genetic data, strain B6(T) represents a novel species from the genus Halomonas, for which the name Halomonas zincidurans sp. nov. is proposed. The type strain is B6(T) ( = CGMCC 1.12450(T) = JCM 18472(T)).

Biogeochemical implications of the ubiquitous colonization of marine habitats and redox gradients by Marinobacter species

The Marinobacter genus comprises widespread marine bacteria, found in localities as diverse as the deep ocean, coastal seawater and sediment, hydrothermal settings, oceanic basalt, sea-ice, sand, solar salterns, and oil fields. Terrestrial sources include saline soil and wine-barrel-decalcification wastewater. The genus was designated in 1992 for the Gram-negative, hydrocarbon-degrading bacterium Marinobacter hydrocarbonoclasticus. Since then, a further 31 type strains have been designated. Nonetheless, the metabolic range of many Marinobacter species remains largely unexplored. Most species have been classified as aerobic heterotrophs, and assessed for limited anaerobic pathways (fermentation or nitrate reduction), whereas studies of low-temperature hydrothermal sediments, basalt at oceanic spreading centers, and phytoplankton have identified species that possess a respiratory repertoire with significant biogeochemical implications. Notable physiological traits include nitrate-dependent Fe(II)-oxidation, arsenic and fumarate redox cycling, and Mn(II) oxidation. There is also evidence for Fe(III) reduction, and metal(loid) detoxification. Considering the ubiquity and metabolic capabilities of the genus, Marinobacter species may perform an important and underestimated role in the biogeochemical cycling of organics and metals in varied marine habitats, and spanning aerobic-to-anoxic redox gradients.

Microbulbifer marinus sp. nov. and Microbulbifer yueqingensis sp. nov., isolated from marine sediment

Two Gram-negative, aerobic strains, Y215T and Y226T, were isolated from sediment from Yueqing Bay, Zhejiang Province, China. The two novel strains were both positive for oxidase activity, nitrate reduction, and aesculin and casein decomposition, but negative for gelatin and tyrosine decomposition. Catalase activity, and starch and Tween 80 decomposition differed between the two strains. Cells of both novel strains were rod-shaped in young cultures and ovoid in older cultures. Optimum NaCl concentration and pH range for growth of both strains were 2.0–3.0 % (w/v) and 7.0–8.0, respectively, whereas the optimum growth temperature for strain Y215T (25–30 °C) was lower than that for strain Y226T (30–37 °C). The genomic DNA G+C contents of strains Y215T and Y226T were 54.0 and 56.7 mol%, respectively. The major fatty acids in both isolates were iso-C15 : 0 and iso-C17 : 1ω9c, which was also the case in the reference strains apart from Microbulbifer salipaludis, which possessed C18 : 1ω7c as the predominant fatty acid. The predominant isoprenoid quinone was Q-8 and the major polar lipids of both strains were phosphatidylethanolamine, phosphatidylglycerol and an unknown glycolipid. Both strains had highest 16S rRNA gene sequence similarity to members of the genus Microbulbifer. Strain Y215T was closely related to the type strains of Microbulbifer maritimus (97.6 %) and Microbulbifer donghaiensis (97.5 %), whereas strain Y226T was closely related to the type strain of M. salipaludis (97.6 %). Phylogenetic analysis based on 16S rRNA gene sequences showed that strains Y215T and Y226T fell into two separate clusters. The DNA–DNA relatedness values of strain Y215T with M. maritimus TF-17T and M. donghaiensis CN85T were 34.1 and 32.8 %, respectively, whereas that between strain Y226T and M. salipaludis SM-1T was 38.0 %; these values are significantly lower than the threshold value for the delineation of bacterial species. On the basis of their distinct taxonomic characteristics, the two isolates represent two novel species of the genus Microbulbifer, for which the names Microbulbifer marinus sp. nov. and Microbulbifer yueqingensis sp. nov. are proposed; the type strains are Y215T ( = CGMCC 1.10657T = JCM 17211T) and Y226T ( = CGMCC 1.10658T = JCM 17212T), respectively.

Marinobacter xestospongiae sp. nov., isolated from the marine sponge Xestospongia testudinaria collected from the Red Sea

A Gram-negative, catalase- and oxidase-positive, non-sporulating, rod-shaped and slightly halophilic bacterial strain, designated UST090418-1611(T), was isolated from the marine sponge Xestospongia testudinaria collected from the Red Sea coast of Saudi Arabia. Phylogenetic trees based on the 16S rRNA gene sequence placed strain UST090418-1611(T) in the family Alteromonadaceae with the closest relationship to the genus Marinobacter. The 16S rRNA gene sequence similarity between the strain and the type strains of recognized Marinobacter species ranged from 92.9 to 98.3%. Although strain UST090418-1611(T) shared high 16S rRNA gene sequence similarity with Marinobacter mobilis CN46(T), M. zhejiangensis CN74(T) and M. sediminum R65(T) (98.3, 97.4 and 97.3%, respectively), the relatedness of the strain to these three strains in DNA-DNA hybridization was only 58, 56 and 33%, respectively, supporting the novelty of the strain. In contrast to most strains in the genus Marinobacter, strain UST090418-1611(T) tolerated only 6% (w/v) NaCl, and optimal growth occurred at 2.0% (w/v) NaCl, pH 7.0-8.0 and 28-36 °C. The predominant cellular fatty acids were C(12:0) 3-OH, C(16:0), C(12:0) and summed feature 3 (C(16:1)ω6c and/or C(16:1)ω7c). The genomic DNA G+C content was 57.1 mol%. Based on the physiological, phylogenetic and chemotaxonomic characteristics presented in this study, we suggest that the strain represents a novel species in the genus Marinobacter, for which the name Marinobacter xestospongiae sp. nov. is proposed, with UST090418-1611(T) ( = JCM 17469(T)  = NRRL B-59512(T)) as the type strain.

Marinobacter antarcticus sp. nov., a halotolerant bacterium isolated from Antarctic intertidal sandy sediment

A Gram-staining-negative, aerobic, motile, oxidase- and catalase-positive, rod-shaped strain, designated ZS2-30(T), was isolated from Antarctic intertidal sandy sediment. The strain grew at 4-35 °C (optimum, 25 °C) and in 0-25% (w/v) NaCl (optimum, 3.0-4.0%). It could reduce nitrate to nitrite and hydrolyse Tween 80. The predominant cellular fatty acids of strain ZS2-30(T) were summed feature 3 (C(16:1)ω7c and/or C(16:1)ω6c), C(16:0), C(18:1)ω9c, C(16:1)ω9c, C(12:0) 3-OH and C(12:0). The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and an unidentified aminophospholipid. The genomic DNA G+C content of strain ZS2-30(T) was 55.8 mol%. Analyses of 16S rRNA gene sequences revealed that strain ZS2-30(T) was affiliated with the genus Marinobacter. It showed highest 16S rRNA gene sequence similarities to the type strains of three species of the genus Marinobacter, namely Marinobacter maritimus (98.3%), Marinobacter psychrophilus (98.1%) and Marinobacter goseongensis (97.1%), but the DNA-DNA relatedness values between strain ZS2-30(T) and the above three species were all lower than 45%. Moreover, strain ZS2-30(T) could be distinguished from closely related species of the genus Marinobacter by various phenotypic properties. Based on this taxonomic study using a polyphasic approach, strain ZS2-30(T) is considered to represent a novel species in the genus Marinobacter, for which the name Marinobacter antarcticus sp. nov. is proposed. The type strain of Marinobacter antarcticus is ZS2-30(T) ( = CGMCC 1.10835(T) = KCTC 23684(T)).

Pelagibacterium halotolerans gen. nov., sp. nov. and Pelagibacterium luteolum sp. nov., novel members of the family Hyphomicrobiaceae

Two Gram-negative, motile, aerobic bacterial strains, designated B2T and 1_C16_27T, were respectively isolated from a seawater sample collected from the East China Sea and a semi-coke sample from north-eastern Estonia. Their genetic, phenotypic and chemotaxonomic properties were studied. The isolates were short rods with polar flagella and were positive for catalase and oxidase activities. Q-10 was the predominant respiratory ubiquinone. The major polar lipids were phosphatidylglycerol, diphosphatidylglycerol and two unidentified glycolipids. The major fatty acids were nonadecanoic (C19 : 0 cyclo), octadecanoic (C18 : 0 and C18 : 0 3-OH), octadecenoic (C18 : 1) and hexadecanoic (C16 : 0) acids. The G+C content of the genomic DNA was 58.1–59.3 mol%. 16S rRNA gene sequence analysis revealed that the two isolates represent a distinct lineage within the family Hyphomicrobiaceae. The phylogenetically closest relatives were Cucumibacter (92.7–93.7 % 16S rRNA gene sequence similarity), Devosia (92.9–94.4 %) and Zhangella (91.7–92.1 %). Differential phenotypic properties, together with phylogenetic and genetic distinctiveness, revealed that strains B2T and 1_C16_27T could be differentiated from each other and from members of the genera Cucumibacter, Devosia and Zhangella. Therefore, it is proposed that strains B2T and 1_C16_27T represent two novel species in a new genus, for which the names Pelagibacterium halotolerans gen. nov., sp. nov. (the type species; type strain B2T  = CGMCC 1.7692T  = JCM 15775T) and Pelagibacterium luteolum sp. nov. (type strain 1_C16_27T  = CGMCC 1.10267T  = JCM 16552T  = CELMS EEUT 1C1627T) are proposed.

Marinobacter daqiaonensis sp. nov., a moderate halophile isolated from a Yellow Sea salt pond

A Gram-negative, oxidase- and catalase-positive, moderately halophilic strain, designated YCSA40(T), was isolated from sediment of Daqiao saltern in Qingdao, on the east coast of China. Growth occurred at 10-45 °C, at pH 5-9 and with 1-15% NaCl. Strain YCSA40(T) showed the highest 16S rRNA gene sequence similarity to Marinobacter segnicrescens SS011B1-4(T) (97%) and M. gudaonensis SL014B61A(T) (96.9%) and 16S rRNA gene sequence phylogenetic analysis assigned the isolate to the genus Marinobacter. Strain YCSA40(T) contained C(18:1)ω9c (34.8%), C(16:0) (11.6%), C(19:0) cyclo ω10c/C(19:1)ω6c (10.5%), C(16:1)ω9c (8.4%), C(17:0) (6.3%) and C(12:0) 3-OH (5.8%) as the predominant fatty acids. The DNA G+C content was 60.8 mol% and the major ubiquinone was Q-9. These chemotaxonomic characters were all consistent with membership of the genus Marinobacter. DNA-DNA relatedness between the isolate and M. segnicrescens CGMCC 1.6489(T), M. gudaonensis CGMCC 1.6294(T) and other type strains of species of the genus Marinobacter was ≤30%. On the basis of the aforementioned data, it was concluded that strain YCSA40(T) represents a novel species of the genus Marinobacter, for which the name Marinobacter daqiaonensis sp. nov. is proposed. The type strain is YCSA40(T) (=CGMCC 1.9167(T) =NCCB 100308(T) =LMG 25365(T)).

Kordiimonas lacus sp. nov., isolated from a ballast water tank, and emended description of the genus Kordiimonas

A Gram-negative, motile, rod-shaped bacterial strain, designated S3-22T, was isolated from a sediment sample collected from a ballast water tank of a commercial ship and subjected to a polyphasic taxonomic characterization. The isolate formed small, light-yellow, semi-translucent and circular colonies on solid complex media. The strain was oxidase- and catalase-positive and metabolized a large number of carbon sources. Chemotaxonomic analysis showed ubiquinone Q-10 as predominant respiratory quinone, phosphatidylglycerol and an unidentified glycolipid as major polar lipids and iso-C17 : 1 ω9c, iso-C15 : 0, C16 : 1 ω7c and/or iso-C15 : 0 2-OH, C16 : 0, iso-C17 : 0 and C18 : 1 ω7c as major fatty acids and the hydroxy fatty acids iso-C17 : 0 3-OH and C16 : 0 3-OH. The genomic DNA G+C content was 54.9 mol%. 16S rRNA gene sequence analysis revealed that the isolate has 96.1 % similarity to the type strain of Kordiimonas gwangyangensis, the sole described species within the order Kordiimonadales, and less than 91.0 % similarity to other recognized species. On the basis of phenotypic and genotypic data, strain S3-22T represents a novel species of the genus Kordiimonas, for which the name Kordiimonas lacus sp. nov. is proposed, with the type strain S3-22T (=CGMCC 1.9109T =JCM 16261T). An emended description of the genus Kordiimonas is also presented.

Oceanobacillus neutriphilus sp. nov., isolated from activated sludge in a bioreactor

A Gram-stain-positive, neutrophilic, rod-shaped bacterium, strain A1g(T), was isolated from activated sludge of a bioreactor and was subjected to a polyphasic taxonomic characterization. The isolate grew in the presence of 0-17.0 % (w/v) NaCl and at pH 6.0-9.0; optimum growth was observed in the presence of 3.0-5.0 % (w/v) NaCl and at pH 7.0. Strain A1g(T) was motile, formed cream-coloured colonies, was catalase- and oxidase-positive and was able to hydrolyse aesculin, Tween 40 and Tween 60. Chemotaxonomic analysis revealed menaquinone-7 as the predominant respiratory quinone and anteiso-C₁₅:₀, anteiso-C₁₇:₀, iso-C₁₆:₀ and iso-C₁₅:₀ as major fatty acids. The genomic DNA G+C content of strain A1g(T) was 36.3 mol%. Comparative 16S rRNA gene sequence analysis revealed that the new isolate belonged to the genus Oceanobacillus and exhibited closest phylogenetic affinity to the type strains of Oceanobacillus oncorhynchi subsp. incaldanensis (97.9 % similarity) and O. oncorhynchi subsp. oncorhynchi (97.5 %), but less than 97 % sequence similarity with respect to the type strains of other recognized Oceanobacillus species. Levels of DNA-DNA relatedness between strain A1g(T) and reference strains O. oncorhynchi subsp. incaldanensis DSM 16557(T), O. oncorhynchi subsp. oncorhynchi JCM 12661(T) and Oceanobacillus iheyensis DSM 14371(T) were 29, 45 and 38 %, respectively. On the basis of phenotypic and genotypic data, strain A1g(T) is considered to represent a novel species of the genus Oceanobacillus, for which the name Oceanobacillus neutriphilus sp. nov. is proposed. The type strain is A1g(T) (=CGMCC 1.7693(T) =JCM 15776(T)).

Microbulbifer donghaiensis sp. nov., isolated from marine sediment of the East China Sea

A Gram-negative, aerobic, neutrophilic, rod-shaped bacterium, designated strain CN85(T), was isolated from a sediment sample collected from the East China Sea and was subjected to a polyphasic taxonomic characterization. This isolate grew in the presence of 0.5-6.0 % (w/v) NaCl and at 20-40 degrees C; optimum growth was observed with 3 % (w/v) NaCl and at 35 degrees C. Chemotaxonomic analysis showed that Q-8 was the predominant respiratory quinone and that iso-C(15 : 0), iso-C(11 : 0) 3-OH, iso-C(17 : 1)omega9c, iso-C(17 : 0), iso-C(11 : 0) and C(16 : 0) were the major fatty acids. The G+C content of the genomic DNA was 57.8 mol%. On the basis of 16S rRNA gene sequence analysis, the isolate was affiliated to the genus Microbulbifer. Strain CN85(T) exhibited most phylogenetic affinity with respect to the type strain of Microbulbifer maritimus (97.0 % sequence similarity) and showed less than 97 % sequence similarity with respect to other described Microbulbifer species with known 16S rRNA gene sequences. The DNA-DNA hybridization between strain CN85(T) and M. maritimus JCM 12187(T) was 44 %. On the basis of phenotypic and genotypic data, strain CN85(T) represents a novel species of the genus Microbulbifer, for which the name Microbulbifer donghaiensis sp. nov. is proposed. The type strain is CN85(T) (=CGMCC 1.7063(T) =JCM 15145(T)).

Marinobacter zhanjiangensis sp. nov., a marine bacterium isolated from sea water of a tidal flat of the South China Sea

A novel Gram-negative, catalase- and oxidase-positive, non-sporulating, rod-shaped, aerobic bacterium, designated strain JSM 078120(T), was isolated from sea water collected from a tidal flat of Naozhou Island, South China Sea. Growth occurred with 1-15% (w/v) total salts (optimum, 2-4%), at pH 6.0-10.0 (optimum, pH 7.5) and at 4-35 degrees C (optimum, 25-30 degrees C). The major cellular fatty acids were C(18:1) omega9c, C(16:0), C(12:0) 3-OH and C(16:1) omega7c. The predominant respiratory quinone was ubiquinone Q-9, and the genomic DNA G + C content was 60.6 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain JSM 078120(T) should be assigned to the genus Marinobacter, being related most closely to the type strains of Marinobacter segnicrescens (sequence similarity 98.2%), Marinobacter bryozoorum (97.9%) and Marinobacter gudaonensis (97.6%). The sequence similarities between the novel isolate and the type strains of other recognized Marinobacter species ranged from 96.7 (with Marinobacter salsuginis) to 93.3% (with Marinobacter litoralis). The levels of DNA-DNA relatedness between strain JSM 078120(T) and the type strains of M. segnicrescens, M. bryozoorum and M. gudaonensis were 25.3, 20.6 and 18.8%, respectively. The combination of phylogenetic analysis, DNA-DNA relatedness, phenotypic characteristics and chemotaxonomic data supported the view that strain JSM 078120(T) represents a novel species of the genus Marinobacter, for which the name Marinobacter zhanjiangensis sp. nov. is proposed. The type strain is JSM 078120(T) (= CCTCC AB 208029(T) = DSM 21077(T) = KCTC 22280(T)).