Complete genome sequence of Algimonas porphyrae type strain LMG 26424, a prosthecate bacterium isolated from the red alga Porphyra yezoensis

Algimonas porphyrae is a dimorphic, prosthecate member of the family Robigintomaculaceae, order Caulobacterales, in the class Alphaproteobacteria, originally isolated from the red alga Porphyra yezoensis. Here we report the complete genome of type strain LMG 26424T (0 C-2-2T) obtained by sequencing with Oxford Nanopore technology.

Alkalicaulis satelles gen. nov., sp. nov., a novel haloalkaliphile isolated from a laboratory culture cyanobacterium Geitlerinema species and proposals of Maricaulaceae fam. nov., Robiginitomaculaceae fam. nov., Maricaulales ord. nov. and Hyphomonadales ord. nov

A prosthecate bacterial strain, designated G-192^T, was isolated from decaying biomass of a haloalkaliphilic cyanobacterium Geitlerinema sp. Z-T0701. The cells were aerobic, Gram-negative, non-endospore-forming and dimorphic, occurring either as sessile bacteria with a characteristic stalk or as motile flagellated cells. The strain utilized a limited range of substrates, mostly peptonaceous, but was able to degrade whole proteins. Growth occurred at 5-46 °C (optimum, 35-40 °C), pH 7.3-10.3 (optimum, pH 8.0-9.0), 0-14 % NaCl (v/w; optimum, 2.0-6.0 %, v/w). The G+C content of the genomic DNA of strain G-192^T was 66.8%. Phylogenetic analysis of the 16S rRNA gene sequence revealed that strain G-192^T formed a distinct evolutionary lineage within the family Hyphomonadaceae. Strain G-192^T showed the highest 16S rRNA sequence similarity to Glycocaulis profundi ZYF765^T (95.2%), Oceanicaulis stylophorae GISW-4^T (94.2%) and Marinicauda salina WD6-1^T (95.5%). The major cellular fatty acids (>5% of the total) were C_18:1 ω9c, C_18:0 and 11-methyl-C_18:1 ω7c. The major polar lipids were glycolipids and phospholipids. The only respiratory quinone was ubiquinone-10 (Q-10). Based on polyphasic results including phylogenomic data, the novel strain could be distinguished from other genera, which suggests that strain G-192^T represents a novel species of a new genus, for which the name Alkalicaulis satelles gen. nov., sp. nov. is proposed. The type strain is G-192^T (=VKM B-3306^T=KCTC 72746^T). The strain is the first representative of the stalked bacteria associated with a haloalkaliphilic cyanobacterium. Based on phylogenomic indices and phenotypic data, it is proposed to evolve two novel families Maricaulaceae fam. nov. and Robiginitomaculaceae fam. nov. out of the current family Hyphomonadaceae. In addition, it is proposed to place the first two families in the novel order Maricaulales ord. nov. and novel order Hyphomonadales ord. nov. is proposed to accommodate the family Hyphomonadaceae.

Bacterial Communities Show Algal Host (Fucus spp.)/Zone Differentiation Across the Stress Gradient of the Intertidal Zone

The intertidal zone often has varying levels of environmental stresses (desiccation, temperature, light) that result in highly stress-tolerant macrobiota occupying the upper zone while less tolerant species occupy the lower zone, but little comparative information is available for intertidal bacteria. Here we describe natural (unmanipulated) bacterial communities of three Fucus congeners (F. spiralis, high zone; F. vesiculosus, mid zone; F. distichus, low zone) as well as those of F. vesiculosus transplanted to the high zone (Dry and Watered treatments) and to the mid zone (Procedural Control) during summer in Maine (United States). We predicted that bacterial communities would be different among the differently zoned natural congeners, and that higher levels of desiccation stress in the high zone would cause bacterial communities of Dry transplants to become similar to F. spiralis, whereas relieving desiccation stress on Watered transplants would maintain the mid-zone F. vesiculosus bacterial community. Bacteria were identified as amplicon sequence variants (ASVs) after sequencing the V4 hypervariable region of the 16S rRNA gene. Microbiome composition and structure were significantly different between the differently zoned congeners at each tissue type (holdfasts, receptacles, vegetative tips). ASVs significantly associated with the mid-zone congener were frequently also present on the high-zone or low-zone congener, whereas overlap in ASVs between the high-zone and low-zone congeners was rare. Only 7 of 6,320 total ASVs were shared among tissues over all congeners and transplant treatments. Holdfast bacterial community composition of Dry transplants was not significantly different from that of F. spiralis, but Watered holdfast communities were significantly different from those of F. spiralis and not significantly different from those of procedural controls. Additional stressor(s) appeared important, because bacterial communities of Dry and Watered transplants were only marginally different from each other (p = 0.059). The relative abundance of Rhodobacteraceae associated with holdfasts generally correlated with environmental stress with highest abundance associated with F. spiralis and the two high-zone transplant treatments. These findings suggest that the abiotic stressors that shape distributional patterns of host species also affect their bacterial communities.

Analysis of 1,000+ Type-Strain Genomes Substantially Improves Taxonomic Classification of Alphaproteobacteria

The class Alphaproteobacteria is comprised of a diverse assemblage of Gram-negative bacteria that includes organisms of varying morphologies, physiologies and habitat preferences many of which are of clinical and ecological importance. Alphaproteobacteria classification has proved to be difficult, not least when taxonomic decisions rested heavily on a limited number of phenotypic features and interpretation of poorly resolved 16S rRNA gene trees. Despite progress in recent years regarding the classification of bacteria assigned to the class, there remains a need to further clarify taxonomic relationships. Here, draft genome sequences of a collection of genomes of more than 1000 Alphaproteobacteria and outgroup type strains were used to infer phylogenetic trees from genome-scale data using the principles drawn from phylogenetic systematics. The majority of taxa were found to be monophyletic but several orders, families and genera, including taxa recognized as problematic long ago but also quite recent taxa, as well as a few species were shown to be in need of revision. According proposals are made for the recognition of new orders, families and genera, as well as the transfer of a variety of species to other genera and of a variety of genera to other families. In addition, emended descriptions are given for many species mainly involving information on DNA G+C content and (approximate) genome size, both of which are confirmed as valuable taxonomic markers. Similarly, analysis of the gene content was shown to provide valuable taxonomic insights in the class. Significant incongruities between 16S rRNA gene and whole genome trees were not found in the class. The incongruities that became obvious when comparing the results of the present study with existing classifications appeared to be caused mainly by insufficiently resolved 16S rRNA gene trees or incomplete taxon sampling. Another probable cause of misclassifications in the past is the partially low overall fit of phenotypic characters to the sequence-based tree. Even though a significant degree of phylogenetic conservation was detected in all characters investigated, the overall fit to the tree varied considerably.

Vitreimonas flagellata gen. nov., sp. nov., a novel member of the family Hyphomonadaceae isolated from an activated sludge sample

A coccobacilli-shaped proteobacterium, designated strain SYSU XM001T, was isolated from an activated sludge sample collected from JiMei sewage treatment plant, Xiamen, PR China. Cells were Gram-stain-negative, catalase-positive and oxidase-negative. The 16S rRNA gene sequence of strain SYSU XM001T shared less than 92 % sequence identities with members of the class Alphaproteobacteria , with highest sequence similarity to Aquidulcibacter paucihalophilus TH1-2T (91.6 %; family Hyphomonadaceae , order Rhodobacterales ). The strain exhibited growth at 25–37 °C, pH 7.0–9.0 and in the presence of up to 1 % (w/v) NaCl. Its chemotaxonomic features included ubiquinone-10 as the respiratory isoprenologue, iso-C16 : 0, 10-methyl C16 : 0 TSBA and anteiso-C17 : 0 as major cellular fatty acids and monoglycosyldiglyceride, glucuronopyranosyldiglyceride and two unidentified glycolipids as the main polar lipids. The DNA G+C content was determined to be 62.9 % (draft genome). Analyses of the phylogenetic data and differences in the chemotaxonomic and biochemical features from related genera in the family Hyphomonadaceae indicated that strain SYSU XM001T merits representation of a novel species of a novel genus, for which the name Vitreimonas flagellata gen. nov., sp. nov. is proposed. The type strain of Vitreimonas flagellata is SYSU XM001T (=CGMCC 1.16661T=KCTC 62915T).

Proposal of Litorimonas haliclonae sp. nov., isolated from a marine sponge of the genus Haliclona

A bright-orange-pigmented, Gram-stain-negative, motile, and rod-shaped bacterium, strain MAA42^T, was isolated from a marine sponge of the genus Haliclona, which is in long-time culture in a marine aquarium system at the Justus Liebig University Giessen, Germany. The strain grew at 4-34 °C (optimum 28 °C), in the presence of 0.5-9.5 % (w/v) NaCl (optimum 3.5 %) and at pH 4.5-10.0 (optimum pH 7.5). Strain MAA42^T shared the highest 16S rRNA gene sequence similarity (98.1 %) with the type strain of Litorimonas taeanensis. Sequence similarities to all other closely related type strains were below 97 %. DNA-DNA hybridization of strain MAA42^T with L. taeanensis DSM 22008^T resulted in values of 4.7 % (reciprocal 17.7 %). Major cellular fatty acids of strain MAA42^T were C18 : 1ω7c (66.2 %), C18 : 1 2-OH (17.4 %), and C18 : 0 (14.1 %). Spermidine was predominant in the polyamine pattern, and ubiquinone Q-10 was the major respiratory quinone. The polar lipid profile contained the major compounds phosphatidylglycerol, monoglycosyldiglyceride, three unidentified phospholipids, and one unidentified glycolipid. Glucuronopyranosyldiglyceride was present as a minor compound. The diagnostic diamino acid of the peptidoglycan was meso-diaminopimelic acid. The genomic DNA G+C content was 52.8 mol%. Based on the genotypic, chemotaxonomic, and phenotypic analyses, strain MAA42^T represents a novel species of the genus Litorimonas, for which the name Litorimonas haliclonae is proposed. The type strain is MAA42^T (=CCM 8709^T=CIP 111178^T=LMG 29765^T).

Algimonas arctica sp. nov., isolated from intertidal sand, and emended description of the genus Algimonas

A novel Gram-reaction-negative, aerobic, pale-orange-pigmented bacterium, designated strain SM1216T, was isolated from Arctic intertidal sand. Cells of strain SM1216T were dimorphic rods with a single polar prostheca or flagellum. The strain grew at 4 − 30 °C (optimum at 25 °C) and with 0.5 − 6 % (w/v) NaCl (optimum with 2 − 3 %). It reduced nitrate to nitrite but did not hydrolyse gelatin, DNA or Tween 80. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain SM1216T was affiliated with the genus Algimonas in the family Hyphomonadaceae, sharing 97.5 and 96.3 % similarity with Algimonas ampicilliniresistens 14A-2-7T and Algimonas porphyrae 0C-2-2T, respectively, the two known species in the genus Algimonas. However, the level of DNA–DNA relatedness between strain SM1216T and the type strain of A. ampicilliniresistens, the nearest phylogenetic neighbour, was 57.9 %. The major cellular fatty acids of strain SM1216T were C18 : 1ω7c and C18 : 1 2-OH. The main polar lipids of strain SM1216T were monoglycosyldiglyceride (MGDG), glucuronopyranosyldiglyceride (GUDG), phosphatidylglycerol (PG) and three unidentified phospholipids (PL1–3). The major respiratory quinone was ubiquinone 10 (Q10). The genomic G+C content of strain SM1216T was 60.6 mol%. On the basis of the evidence from this polyphasic study, strain SM1216T represents a novel species in the genus Algimonas, for which the name Algimonas arctica sp. nov. is proposed. The type strain is SM1216T ( = MCCC 1K00233T = KCTC 32513T). An emended description of the genus Algimonas is also given.

Aestuariicella hydrocarbonica gen. nov., sp. nov., an aliphatic hydrocarbon-degrading bacterium isolated from a sea tidal flat

A Gram-staining-negative, strictly aerobic bacterial strain, designated SM-6T, was isolated from a sea tidal flat of the Dangjin bay, South Korea. Strain SM-6T was able to degrade a broad range of aliphatic hydrocarbons. Cells were catalase- and oxidase-positive and non-motile rods. Growth of strain SM-6T was observed at 10-37 °C (optimum, 20-25 °C), at pH 5.5-9.0 (optimum, pH 6.5-7.5) and in the presence of 0-10 % (w/v) NaCl (optimum, 2-3 %). The only isoprenoid quinone detected was ubiquinone-8 (Q-8). C17:1ω8c, C11:0 3-OH, summed feature 3 (comprising C16:1ω7c and/or C16:1ω6c), C9:0 3-OH and C10:0 3-OH were observed as the major cellular fatty acids and phosphatidylethanolamine, phosphatidylglycerol and four unidentified lipids were detected as polar lipids. The G+C content of the genomic DNA was 47.5 mol%. Strain SM-6T was most closely related to Pseudomaricurvus alkylphenolicus KU41GT (95.5 %), Maricurvus nonylphenolicus KU41ET (94.4 %) and Pseudoteredinibacter isoporae SW-11T (94.3 %), based on 16S rRNA gene sequences, and phylogenetic analyses showed that strain SM-6T formed a phyletic lineage distinct from the closely related genera. On the basis of phenotypic, chemotaxonomic and molecular features, strain SM-6T represents a novel genus and species of the order Alteromonadales in the class Gammaproteobacteria, for which name Aestuariicella hydrocarbonica gen. nov., sp. nov. is proposed. The type strain is SM-6T ( = KACC 18121T = JCM 30134T).

Zhongshania aliphaticivorans sp. nov., an aliphatic hydrocarbon-degrading bacterium isolated from marine sediment, and transfer of Spongiibacter borealis Jang et al. 2011 to the genus Zhongshania as Zhongshania borealis comb. nov

A Gram-staining-negative, facultatively aerobic bacterium, designated SM-2(T), was isolated from a sea-tidal flat of Yellow Sea, South Korea. Cells were catalase- and oxidase-positive motile rods with a single polar flagellum. Growth of strain SM-2(T) was observed at 10-37 °C (optimum, 25-30 °C), at pH 5.5-8.5 (optimum, pH 7.0-7.5) and in the presence of 0-11% (w/v) NaCl (optimum, 2%). Strain SM-2(T) contained ubiquinone-8 (Q-8) as the sole isoprenoid quinone and C(17:1)ω8c, summed feature 3 (comprising C(16:1)ω7c and/or iso-C(15:0) 2-OH), C(17:0) and C(18:1)ω7c as the major fatty acids. Phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and an unidentified lipid were identified as the major cellular polar lipids. The G+C content of the genomic DNA was 52.2 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain SM-2(T) formed a tight phyletic lineage with Zhongshania antarctica ZS5-23(T), Zhongshania guokunii ZS6-22(T) and Spongiibacter borealis CL-AS9(T), but that S. borealis CL-AS9(T) was distinct from other species of the genus Spongiibacter. Based on 16S rRNA gene sequence similarities, strain SM-2(T) was most closely related to S. borealis CL-AS9(T), Z. antarctica ZS5-23(T) and Z. guokunii ZS6-22(T), with similarities of 99.5%, 98.9% and 98.7%, respectively, but the DNA-DNA hybridization values among these species were clearly lower than 70%. On the basis of chemotaxonomic data and molecular properties, we propose strain SM-2(T) represents a novel species of the genus Zhongshania with the name Zhongshania aliphaticivorans sp. nov. (type strain SM-2(T) =KACC 18120(T) =JCM 30138(T)). We also propose the transfer of Spongiibacter borealis Jang et al. 2011 to the genus Zhongshania as Zhongshania borealis comb. nov. (type strain CL-AS9(T) =KCCM 90094(T) =JCM 17304(T)).

Fretibacter rubidus gen. nov., sp. nov., isolated from seawater

A brick-red-coloured, curved-rod-shaped, prostheca-bearing and non-motile bacterial strain, designated JC2236T, was isolated from a seawater sample of Jeju Island, Republic of Korea. 16S rRNA gene sequence analysis indicated that this strain belongs to the family Hyphomonadaceae and represents a distinct phyletic line that reflects a novel genus status within a clade containing the genera Litorimonas , Hellea , Robiginitomaculum and Algimonas . The predominant isoprenoid quinone (Q10) and polar lipid profile (phosphatidylglycerol, glucuronopyranosyl diglyceride and monoglycosyl diglyderide) were in line with those of most members of the family. However, the DNA G+C content (49.3 mol%), the abundance of C16 : 0, the requirement of sea salts for growth and absence of cell motility differentiated strain JC2236T from other closely related genera. Overall enzyme traits also demonstrated that the novel strain is not closely affiliated with any of the previously described genera. Thus, based on data from the present polyphasic taxonomic study, strain JC2236T is considered to represent a novel species of a new genus belonging to the family Hyphomonadaceae , for which the name Fretibacter rubidus gen. nov., sp. nov. is proposed. The type strain of Fretibacter rubidus is JC2236T ( = KACC 16935T = JCM 15585T).

Aquamicrobium aestuarii sp. nov., a marine bacterium isolated from a tidal flat

A Gram-negative, strictly aerobic, motile bacterium with flagella, designated strain G210T, was isolated from a crude-oil-contaminated tidal flat of the Taean coast in South Korea. Cells were non-spore-forming, ovoid rods showing catalase- and oxidase-positive reactions. Growth of strain G210T was observed between 15 and 45 °C (optimum, 30–35 °C) and between pH 5.5 and 9.0 (optimum, pH 6.5–7.5). Strain G210T contained Q-10 as the sole isoprenoid quinone and summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c) and C19 : 0 cyclo ω8c as the major fatty acids. Putrescine and spermidine were identified as the major polyamines. Strain G210T contained phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, phosphatidylmonomethylethanolamine, an unidentified phospholipid and an unidentified aminolipid as polar lipids. The G+C content of the genomic DNA was 56.9 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain G210T formed a phyletic lineage with members of the genus Aquamicrobium . Strain G210T was most closely related to Aquamicrobium ahrensii 905/1T (97.9 % similarity). The DNA–DNA relatedness between strain G210T and the type strain of A. ahrensii was 24±0.5 %. On the basis of phenotypic, chemotaxonomic and molecular properties, strain G210T represents a novel species within the genus Aquamicrobium , for which the name Aquamicrobium aestuarii sp. nov. is proposed. The type strain is G210T ( = KACC 14931T = JCM 16876T).

Maribacter aestuarii sp. nov., isolated from tidal flat sediment, and an emended description of the genus Maribacter

A Gram-staining-negative, strictly aerobic bacterial strain, motile by gliding, designated GY20T, was isolated from a tidal flat at Gwangyang Bay, South Korea. Cells were moderately halophilic, catalase- and oxidase-positive rods. Growth of strain GY20T was observed at 10–30 °C (optimum, 25 °C), at pH 6.5–11.0 (optimum, pH 7.0–8.0) and in the presence of 1–5 % (w/v) NaCl (optimum, 2–3 %). MK-6 was detected as the sole isoprenoid quinone, and iso-C15 : 0, iso-C15 : 1 G, summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c), summed feature 9 (iso-C17 : 1ω9c and/or 10-methyl C16 : 0), iso-C17 : 0 3-OH and iso-C15 : 0 3-OH as major fatty acids. Strain GY20T contained phosphatidylethanolamine, one unidentified glycolipid and one unidentified lipid as major polar lipids. The G+C content of the genomic DNA was 39.8 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain GY20T formed a tight phyletic lineage with members of the genus Maribacter . Strain GY20T was most closely related to Maribacter dokdonensis DSW-8T, with sequence similarity of 96.2 %. On the basis of phenotypic, chemotaxonomic and molecular properties, strain GY20T was shown to represent a novel species within the genus Maribacter , for which the name Maribacter aestuarii sp. nov. is proposed. The type strain is GY20T ( = KACC 16440T = JCM 18631T). An emended description of the genus Maribacter is also proposed.

Muricauda taeanensis sp. nov., isolated from a marine tidal flat

A novel Gram-stain-negative, heterotrophic, moderate halophilic and strictly aerobic bacterium, strain 105T, was isolated from a tidal flat of Taean in Korea. Cells were catalase- and oxidase-positive long rods that showed gliding motility. Optimum temperature, pH and salinity for the growth of strain 105T were observed at 30–37 °C, at pH 7.0–7.5, and in the presence of 2–4 % (w/v) NaCl, respectively. The major cellular fatty acids were iso-C15 : 1 G, iso-C15 : 0 and iso-C17 : 0 3-OH. Phosphatidylethanolamine and five unidentified lipids were identified as the major polar lipids. The genomic DNA G+C content of strain 105T was 42.4 mol% and MK-6 was detected as the predominant isoprenoid quinone. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain 105T formed a phyletic lineage with members of the genus Muricauda . Strain 105T was most closely related to Muricauda aquimarina SW-63T (97.6 %), Muricauda beolgyonensis BB-My12T (97.5 %), Muricauda lutimaris SMK-108T (97.5 %), Muricauda ruestringensis B1T (97.3 %), Muricauda flavescens CL-SS4T (97.2 %) and Muricauda olearia (96.2 %). The DNA–DNA relatedness values of strain 105T with M. aquimarina JCM 11811T, M. beolgyonensis KCTC 23501T, M. lutimaris KCTC 22173T, M. ruestringensis DSM 13258T and M. flavescens JCM 11812T were 17.2±6.0, 8.7±2.2, 3.7±0.5, 11.0±1.9 and 7.1±1.3 %, respectively. On the basis of phenotypic and molecular features, strain 105T represents a novel species of the genus Muricauda , for which the name Muricauda taeanensis sp. nov. is proposed. The type strain is 105T ( = KACC 16195T = JCM 17757T).

Marinicauda pacifica gen. nov., sp. nov., a prosthecate alphaproteobacterium of the family Hyphomonadaceae isolated from deep seawater

A marine prosthecate bacterium, designated strain P-1 km-3T, was isolated from deep seawater from the Pacific. Cells of strain P-1 km-3T were Gram-stain-negative, aerobic, catalase- and oxidase-positive, dimorphic rods with a single polar prostheca or flagellum. The strain hydrolysed gelatin and grew at 6–40 °C (optimum, 30 °C) and with 0.5–12 % (w/v) NaCl (optimum, 2 %). Phylogenetic analysis of the 16S rRNA gene sequences revealed that strain P-1 km-3T belonged to the family Hyphomonadaceae in the class Alphaproteobacteria and represented a separate lineage, located between the genera Oceanicaulis and Woodsholea . Sequence similarities of strain P-1 km-3T with type strains of species of the genera Oceanicaulis and Woodsholea were 93.2–93.9 %. The predominant cellular fatty acids in strain P-1 km-3T were C18 : 1ω7c, C18 : 0, 11-methyl C18 : 1ω7c, C17 : 0 and C19 : 0 cyclo ω8c. The major respiratory quinone of strain P-1 km-3T was Q-10. The polar lipids of strain P-1 km-3T comprised glucuronopyranosyldiglyceride (GUDG), monoglycosyldiglyceride (MGDG), sulfo-quinovosyl diacylglycerol (SQDG), phosphatidylglycerol (PG), an unidentified phospholipid (PL) and an unidentified lipid (L). The genomic DNA G+C content of strain P-1 km-3T was 66.0 mol%. On the basis of the polyphasic data presented in this study, strain P-1 km-3T is proposed to represent a novel species in a new genus, Marinicauda pacifica gen. nov., sp. nov., within the family Hyphomonadaceae . The type strain of the type species is P-1 km-3T ( = KACC 16526T = CGMCC 1.11031T).

Microbulbifer gwangyangensis sp. nov. and Microbulbifer pacificus sp. nov., isolated from marine environments

Two novel Gram-stain-negative, chemoheterotrophic and strictly aerobic bacteria, strains GY2T and SPO729T, were isolated from a tidal flat at Gwangyang Bay in Korea and a marine sponge sample from the Pacific Ocean, respectively. The two strains were halotolerant, catalase- and oxidase-positive, and non-motile rods. Optimum temperature and pH for growth of both strains were observed to be 35 °C and pH 7.0–7.5, but optimum salinity for strain SPO729T [2–3 % (w/v)] was slightly higher than that for strain GY2T (1–2 %). The major cellular fatty acids of both strains were C16 : 0, iso-C15 : 0, iso-C17 : 0, iso-C17 : 1ω9c, C18 : 1ω7c, iso-C11 : 0 and iso-C11 : 0 3-OH. The genomic DNA G+C contents of strains GY2T and SPO729T were 55.1 and 57.9 mol%, respectively, and ubiquinone 8 (Q-8) was detected as the sole respiratory quinone from the two strains. Phylogenetic analysis based on 16S rRNA gene sequences showed that strains GY2T and SPO729T formed tight phyletic lineages with members of the genus Microbulbifer . Strain GY2T was closely related to Microbulbifer okinawensis ABABA23T (98.2 %), strain SPO729T (98.0 %) and Microbulbifer donghaiensis CN85T (97.0 %); strain SPO729T was closely related to M. okinawensis ABABA23T (98.3 %) and M. donghaiensis CN85T (98.2 %). The DNA–DNA relatedness values of strain GY2T with M. okinawensis ABABA23T, strain SPO729T and M. donghaiensis CN85T were 40.0±2.1 %, 13.1±3.9 % and 16.2±5.8 %, respectively, whereas those of strain SPO729T with M. okinawensis ABABA23T and M. donghaiensis CN85T were 48.0±4.0 % and 34.6±9.3 %, respectively. On the basis of phenotypic and molecular features, it is concluded that the two strains GY2T and SPO729T represent two novel species of the genus Microbulbifer , for which the names Microbulbifer gwangyangensis sp. nov. and Microbulbifer pacificus are proposed; the type strains are GY2T ( = KACC 16189T = JCM 17800T) and SPO729T ( = KCCM 42667T = JCM 14507T), respectively.

Microbial succession and metabolite changes during fermentation of dongchimi, traditional Korean watery kimchi

Dongchimi, one of the most common types of watery kimchi in Korea, was prepared using radish and its pH values, microbial cell numbers, bacterial communities, and metabolites were monitored periodically to investigate the fermentation process of watery kimchi. The bacterial abundance increased quickly during the early fermentation period and the pH values concurrently decreased rapidly without any initial pH increase. After 15 days of fermentation, the bacterial abundance decreased rapidly with the increase of Saccharomyces abundance and then increased again with a decrease of Saccharomyces abundance after 40 days of fermentation, suggesting that bacteria and Saccharomyces have a direct antagonistic relationship. Finally, after 60 days of fermentation, a decrease in bacterial abundance and the growth of Candida were concurrently observed. Community analysis using pyrosequencing revealed that diverse genera such as Leuconostoc, Lactobacillus, Pseudomonas, Pantoea, and Weissella were present at initial fermentation (day 0), but Leuconostoc became predominant within only three days of fermentation and remained predominant until the end of fermentation (day 100). Metabolite analysis using (1)H NMR showed that the concentrations of free sugars (fructose and glucose) were very low during the early fermentation period, but their concentrations increased rapidly although lactate, mannitol, and acetate were produced. After 30 days of fermentation, quick consumption of free sugars and production of glycerol and ethanol were observed concurrently with the growth of Saccharomyces, levels of which might be considered for use as a potential indicator of dongchimi quality and fermentation time.

Litorimonas cladophorae sp. nov., a new alphaproteobacterium isolated from the Pacific green alga Cladophora stimpsoni, and emended descriptions of the genus Litorimonas and Litorimonas taeaensis

A strictly aerobic, Gram-stain-negative, rod-shaped and red-orange pigmented bacterium, designated strain KMM 6395(T), was isolated from the green alga Cladophora stimpsoni and subjected to a polyphasic taxonomic study. Phylogenetic analysis based on 16S rRNA gene sequencing revealed that the novel strain affiliated to the family Hyphomonadaceae of the class Alphaproteobacteria being most closely related to the type strain of the single species of the genus Litorimonas, Litorimonas taeanensis G5(T), with 16S rRNA gene sequence similarity of 96.8 %. Strain KMM 6395(T) grew with 1-5 % NaCl and at 4-35 °C, hydrolysed starch and Tween 80. The DNA G+C content was 48.7 mol%. The prevalent fatty acids were C18:1 ω7c, C19:1 ω8c and C18:1 ω7c 10-methyl. The polar lipid profile was characterized by the presence of phosphatidylglycerol, monoglycosyldiglyceride, glucuronopyranosyldiglyceride and an unidentified glycolipid. The major respiratory quinone was Q-10. The significant molecular distinctiveness between the novel isolate and its nearest neighbour, L. taeanensis G5(T), were strongly supported by the differences in physiological and biochemical tests. Therefore, strain KMM 6395(T) represents a novel species of the genus Litorimonas, for which the name Litorimonas cladophorae sp. nov. is proposed. The type strain is KMM 6395(T) (=KCTC 23968(T) = LMG 26985(T)). The emended descriptions of the genus Litorimonas and L. taeaensis are also provided.

Altererythrobacter gangjinensis sp. nov., a marine bacterium isolated from a tidal flat

A Gram-stain-negative, ochre-pigmented, strictly aerobic bacterium, designated strain KJ7T, was isolated from a tidal flat of the Gangjin bay in South Korea. Cells were halotolerant, non-motile, catalase- and oxidase-positive rods. Growth of strain KJ7T was observed at 5–35 °C (optimum, 25 °C), at pH 6.0–9.5 (optimum, pH 6.5–7.0) and in the presence of 0–9 % (w/v) NaCl (optimum, 2 %). The major cellular fatty acids were C18 : 1ω7c, C17 : 1ω6c, summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c) and C16 : 0. The polar lipid pattern indicated the presence of phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, a sphingoglycolipid, an unidentified phospholipid and two unidentified lipids. The G+C content of the genomic DNA was 60.2±0.9 mol% and the predominant respiratory quinone was Q-10. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain KJ7T formed a phyletic lineage distinct from other members of the genus Altererythrobacter and was most closely related to Altererythrobacter luteolus SW-109T and Altererythrobacter namhicola KYW48T (95.6 and 95.0 % 16S rRNA gene sequence similarity, respectively). On the basis of phenotypic, chemotaxonomic and molecular features, strain KJ7T represents a novel species of the genus Altererythrobacter , for which the name Altererythrobacter gangjinensis sp. nov. is proposed. The type strain is KJ7T ( = KACC 16190T = JCM 17802T).

Arenibacter hampyeongensis sp. nov., a marine bacterium isolated from a tidal flat

A Gram-staining-negative, dark orange, strictly aerobic bacterium, designated strain HP12T, was isolated from a tidal flat at Hampyeong in South Korea. Cells were moderately halotolerant, catalase- and oxidase-positive, non-motile rods. Growth was observed at 5–35 °C (optimum, 25 °C), at pH 6.0–8.5 (optimum, pH 7.0–7.5), and in the presence of 1–6 % (w/v) NaCl (optimum, 1–2 %). The major cellular fatty acids were summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH), iso-C17 : 0 3-OH, C15 : 0, iso-C15 : 1 G and iso-C15 : 0. The polar lipid pattern indicated the presence of phosphatidylethanolamine and two unidentified lipids. The G+C content of the genomic DNA was 37.1 mol% and the predominant respiratory quinone was menaquinone-6. Phylogenetic analysis based on 16S rRNA gene sequences showed that the novel strain formed a tight phyletic lineage with members of the genus Arenibacter and was most closely related to Arenibacter palladensis KMM 3961T, Arenibacter troitsensis KMM 3674T and Arenibacter echinorum KMM 6032T, with 16S rRNA gene sequence similarities of 98.1 %, 98.0 % and 97.8 %, respectively. However, the DNA–DNA relatedness values between strain HP12T and A. palladensis JCM 13509T, A. troitsensis KCTC 12362T and A. echinorum KCTC 22013T were only 20.2±0.3 %, 22.6±0.6 % and 9.1±2.6 %, respectively. On the basis of phenotypic and molecular features, strain HP12T represents a novel species of the genus Arenibacter , for which the name Arenibacter hampyeongensis sp. nov. is proposed. The type strain is HP12T ( = KACC 16193T = JCM 17788T).

Defluviimonas aestuarii sp. nov., a marine bacterium isolated from a tidal flat, and emended description of the genus Defluviimonas Foesel et al. 2011

A novel Gram-staining-negative, strictly aerobic bacterium, designated BS14(T), was isolated from a marine tidal flat of the South Sea in Korea. Colonies were opaque, white, smooth and circular on marine agar. Cells were moderately halophilic, non-motile rods showing catalase- and oxidase-positive reactions. Growth of strain BS14(T) was observed at 5-40 °C (optimum: 30 °C), pH 6.5-9.5 (optimum: 7.0-7.5) and 0-10 % (w/v) NaCl (optimum: 1-1.5 %). The G+C content of the genomic DNA was 61.6 mol%. Strain BS14(T) contained ubiquinone-10 (Q-10) as the sole respiratory quinone and summed feature 8 (comprising C18 : 1ω7c and/or C18 : 1ω6c), C18 : 0 3-OH, C10 : 0 3-OH and C18 : 0 as the major fatty acids. The polar lipid pattern comprised phosphatidylethanolamine, diphosphatidylglycerol, an unidentified aminolipid, an unidentified phospholipid and an unidentified polar lipid. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain BS14(T) formed a tight phylogenetic lineage with Defluviimonas denitrificans D9-3(T) with a bootstrap value of 100 %. The 16S rRNA gene sequence similarity between strain BS14(T) and D. denitrificans D9-3(T) was 97.4 % and their DNA-DNA relatedness was 19.1 ± 3.6 %. Based on the phenotypic and genotypic studies, strain BS14(T) represents a novel species of the genus Defluviimonas, for which the name Defluviimonas aestuarii sp. nov. is proposed. The type strain is BS14(T) (= KACC 16442(T) = JCM 18630(T)). An emended description of the genus Defluviimonas Foesel et al. 2011 is also proposed.

Aestuariibaculum suncheonense gen. nov., sp. nov., a marine bacterium of the family Flavobacteriaceae isolated from a tidal flat and emended descriptions of the genera Gaetbulibacter and Tamlana

A Gram-staining-negative, yellow-pigmented, strictly aerobic bacterium, designated strain SC17T, was isolated from sediment of a tidal flat of Suncheon bay in South Korea. Cells were halotolerant, catalase- and oxidase-positive and non-motile rods. Growth of strain SC17T was observed at 5–40 °C (optimum, 25–30 °C), at pH 6.0–8.5 (optimum, pH 7.0) and in the presence of 1–8 % (w/v) NaCl (optimum, 1–2 %). The major cellular fatty acids were iso-C15 : 0, summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c and/or iso-C15 : 0 2-OH), iso-C17 : 0 3-OH, iso-C15 : 1 G and anteiso-C15 : 0. The polar lipid content consisted of phosphatidylethanolamine and unidentified amino lipids and lipids. The G+C content of the genomic DNA was 46.4 mol% and the only respiratory quinone detected was menaquinone-6 (MK-6). Phylogenetic inference based on 16S rRNA gene sequences showed that strain SC17T formed a distinct phyletic lineage within the family Flavobacteriaceae and was most closely related to members of the genera Gaetbulibacter and Tamlana with 95.0–95.8 % sequence similarity. On the basis of phenotypic and molecular features, strain SC17T represents a novel genus of the family Flavobacteriaceae , for which the name Aestuariibaculum suncheonense gen. nov., sp. nov. is proposed. The type strain is SC17T ( = KACC 16186T = JCM 17789T). Emended descriptions of the genera Gaetbulibacter and Tamlana are also proposed.

Kordiimonas aestuarii sp. nov., a marine bacterium isolated from a tidal flat

A Gram-staining negative, strictly aerobic bacterium, designated 101-1T, was isolated from a sea tidal flat, Taean, Korea. The strain formed small light-yellow, smooth, and circular colonies on marine agar. Cells were weakly halophilic, motile rods showing catalase- and oxidase-positive reactions. Growth of strain 101-1T was observed at 15–40 °C (optimum, 30 °C), pH 5.0–8.0 (optimum, pH 6.5–7.0) and 1.0–9.0 % (w/v) NaCl (optimum, 2.0–3.5 %). The G+C content of the genomic DNA was 53.3 mol%. Strain 101-1T contained ubiquinone-10 (Q-10) as the respiratory quinone and iso-C17 : 1ω9c, iso-C15 : 0 and iso-C17 : 0 as major fatty acids. Phylogenetic analyses based on 16S rRNA gene sequences showed that strain 101-1T formed a tight phylogenetic lineage with members of the genus Kordiimonas and was most closely related to Kordiimonas gwangyangensis GW14-5T and Kordiimonas lacus S3-22T with 97.3 % and 96.3 % 16S rRNA gene sequence similarities, respectively. The DNA–DNA relatedness values between strain 101-1T and K. gwangyangensis GW14-5T and K. lacus S3-22T were 24.8±4.4 % and 32.2±3.6 %, respectively. Based on the data from the phenotypic and genotypic studies, strain 101-1T represents a novel species of the genus Kordiimonas , for which the name Kordiimonas aestuarii sp. nov. is proposed. The type strain is 101-1T ( = KACC 16184T = JCM 17742T).

Halomonas cibimaris sp. nov., isolated from jeotgal, a traditional Korean fermented seafood

Two moderately halophilic, facultatively aerobic, motile bacteria with flagella, designated strains 10-C-3(T) and 30-C-3, were isolated from jeotgal, a traditional Korean fermented seafood. Cells of the strains were observed to be ovoid-rods showing catalase- and oxidase-positive reactions and production of creamy-pink pigments. Growth of strain 10-C-3(T) was observed at 15-35 °C (optimum, 25-30 °C), at pH 5.5-9.0 (optimum, pH 7.0-7.5), and in the presence of 3-15 % (w/v) salts (optimum: 5-10 %). The two strains were found to contain C(18:1) ω7c, C(16:0), summed feature 3 (as defined by the MIDI system, comprising C(16:1) ω7c and/or C(16:1) ω6c), and C(12:0) 3-OH as the major cellular fatty acids. The G+C contents of the genomic DNA of strains 10-C-3(T) and 30-C-3 were determined to be 63.2 and 63.1 mol%, respectively and the respiratory quinone detected was ubiquinone 9 (Q-9) only. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strains 10-C-3(T)and 30-C-3 formed a distinct phyletic lineage within the genus Halomonas and are most closely related to Halomonas fontilapidosi 5CR(T) with 95.2 % of 16S rRNA sequence similarity. Strains 10-C-3(T)and 30-C-3 shared 99.2 % of 16S rRNA gene sequence similarity and their DNA-DNA relatedness value was 96.6 ± 0.9 %. On the basis of phenotypic, chemotaxonomic and molecular features, strains 10-C-3(T)and 30-C-3 represent a novel species of the genus Halomonas, for which the name Halomonas cibimaris sp. nov. is proposed. The type strain is 10-C-3(T) (= KACC 14932(T) = JCM 16914(T)).

Algimonas porphyrae gen. nov., sp. nov., a member of the family Hyphomonadaceae, isolated from the red alga Porphyra yezoensis

Three Gram-negative, stalked, motile bacteria, designated 0C-2-2(T), 0C-17 and LNM-3, were isolated from the red alga Porphyra yezoensis. 16S rRNA gene sequence analysis revealed that the three novel strains belonged to the family Hyphomonadaceae, and were closely related to Litorimonas taeanensis G5(T) (96.5 % 16S rRNA gene sequence similarity) and Hellea balneolensis 26III/A02/215(T) (94.3 %). The DNA G+C contents of the novel isolates (58.5-60.2 mol%) were clearly distinguished from those of L. taeanensis G5(T) (47.1 mol%) and H. balneolensis DSM 19091(T) (47.9 mol%). The G+C content of L. taeanensis G5(T) obtained in this study was quite different from a previous report (63.6 mol%). DNA-DNA hybridization experiments showed that the novel strains constituted a single species. Eleven phenotypic features of the three isolates differed from those of both related genera. The predominant respiratory quinone was ubiquinone-10 and the major fatty acid was C(18 : 1)ω7c. On the basis of this polyphasic taxonomic analysis, the novel strains represent a novel genus and species, for which the name Algimonas porphyrae gen. nov., sp. nov. is proposed. The type strain of Algimonas porphyrae is 0C-2-2(T) (= LMG 26424(T) = NBRC 108216(T)).

Pusillimonas harenae sp. nov., isolated from a sandy beach, and emended description of the genus Pusillimonas

A Gram-stain-negative, motile bacterium with two lateral flagella, designated strain B201T, was isolated from beach sand from the Taean coast in South Korea. Cells were ovoid rods and positive for catalase and oxidase. Growth of strain B201T was observed between 15 and 45 °C (optimum, 30 °C) and between pH 5.0 and 9.0 (optimum, pH 6.0–7.5). Strain B201T contained ubiquinone Q-8 as the major isoprenoid quinone, but MK-6 was also present as a minor quinone. The major fatty acids of strain B201T were C17 : 0 cyclo, C16 : 0, summed feature 2 (iso-C16 : 1 I/C14 : 0 3-OH and/or C12 : 0 ALDE), C12 : 0 and C19 : 0 cyclo ω8c. The major cellular polar lipids were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, an unidentified phospholipid and three aminolipids. The genomic DNA G+C content was 53.1 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that the strain formed a phyletic lineage with Pusillimonas ginsengisoli DCY25T within the genus Pusillimonas. Strain B201T was most closely related to P. ginsengisoli DCY25T and Pusillimonas soli MJ07T with similarities of 98.6 and 97.5 %, respectively. However, DNA–DNA relatedness values of strain B201T with P. ginsengisoli DCY25T and P. soli MJ07T were 30.2±5.4 and 4.9±1.8 %, respectively. On the basis of chemotaxonomic data and molecular properties, strain B201T represents a novel species of the genus Pusillimonas, for which the name Pusillimonas harenae sp. nov. is proposed; the type strain is B201T ( = KACC 14927T = JCM 16917T). An emended description of the genus Pusillimonas is given.

Citreicella aestuarii sp. nov., isolated from a tidal flat

A Gram-negative bacterium, designated AD8T, was isolated from a tidal flat of the Taean coast in South Korea. Cells were strictly aerobic, motile, ovoid rods or rods, with two lateral flagella on one side. Strain AD8T was catalase- and oxidase-positive and able to oxidize thiosulfate and reduce nitrate to nitrite. Growth of strain AD8T was observed at 15–40 °C (optimum 25–30 °C), at pH 5.0–9.5 (optimum pH 6.0–7.5) and with 1.0–11.0 % (w/v) NaCl (optimum 2.0–4.0 %). The predominant fatty acids were C18 : 1ω7c and C19 : 0 cyclo ω8c. The G+C content of the genomic DNA was 67.5 mol% and the major quinone was Q-10. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain AD8T belonged to the genus Citreicella and was most closely related to Citreicella marina CK-I3-6T within the class Alphaproteobacteria (96.9 % 16S rRNA gene sequence similarity). On the basis of phenotypic, chemotaxonomic and phylogenetic analysis, strain AD8T represents a novel species within the genus Citreicella, for which the name Citreicella aestuarii sp. nov. is proposed. The type strain is AD8T ( = KACC 13699T  = DSM 22011T).