Complete genome sequence and potential pathogenic assessment of Flavobacterium plurextorum RSG-18 isolated from the gut of Schlegel's black rockfish, Sebastes schlegelii.

Flavobacterium plurextorum is a potential fish pathogen of interest, previously isolated from diseased rainbow trout (Oncorhynchus mykiss) and oomycete-infected chum salmon (Oncorhynchus keta) eggs. We report here the first complete genome sequence of F. plurextorum RSG-18 isolated from the gut of Schlegel's black rockfish (Sebastes schlegelii). The genome of RSG-18 consists of a circular chromosome of 5,610,911 bp with a 33.57% GC content, containing 4858 protein-coding genes, 18 rRNAs, 63 tRNAs and 1 tmRNA. A comparative analysis was conducted on 11 Flavobacterium species previously reported as pathogens or isolated from diseased fish to confirm the potential pathogenicity of RSG-18. In the SEED classification, RSG-18 was found to have 36 genes categorized in 'Virulence, Disease and Defense'. Across all Flavobacterium species, a total of 16 antibiotic resistance genes and 61 putative virulence factors were identified. All species had at least one phage region and type I, III and IX secretion systems. In pan-genomic analysis, core genes consist of genes linked to phages, integrases and matrix-tolerated elements associated with pathology. The complete genome sequence of F. plurextorum RSG-18 will serve as a foundation for future research, enhancing our understanding of Flavobacterium pathogenicity in fish and contributing to the development of effective prevention strategies.

Transcriptomic profiling and the first spatial expression analysis of candidate genes in the salivary gland of the East Asian medicinal leech, Hirudo nipponia.

Hirudo nipponia, a blood-sucking leech native to East Asia, possesses a rich repertoire of active ingredients in its saliva, showcasing significant medical potential due to its anticoagulant, anti-inflammatory, and antibacterial effects against human diseases. Despite previous studies on the transcriptomic and proteomic characteristics of leech saliva, which have identified medicinal compounds, our knowledge of tissue-specific transcriptomes and their spatial expression patterns remains incomplete. In this study, we conducted an extensive transcriptomic profiling of the salivary gland tissue in H. nipponia based on de novo assemblies of tissue-specific transcriptomes from the salivary gland, teeth, and general head region. Through gene ontology (GO) analysis and hierarchical clustering, we discovered a novel set of anti-coagulant factors-i.e., Hni-Antistasin, Hni-Ghilanten, Hni-Bdellin, Hni-Hirudin-as well as a previously unrecognized immune-related gene, Hni-GLIPR1 and uncharacterized salivary gland specific transcripts. By employing in situ hybridization, we provided the first visualization of gene expression sites within the salivary gland of H. nipponia. Our findings expand on our understanding of transcripts specifically expressed in the salivary gland of blood-sucking leeches, offering valuable resources for the exploration of previously unidentified substances with medicinal applications.

Paenibacillus caseinilyticus sp. nov., isolated forest soil.

A milky-white-coloured, aerobic, Gram-stain-positive, rod-shaped and motile bacterial strain (GW78T) was isolated from forest soil. GW78T was catalase-positive and oxidase-negative. The strain was able to grow optimally at 37 °C and at pH 7.0 in Reasoner's 2A media. The phylogenetic and 16S rRNA gene sequence analysis of GW78T showed its affiliation with the genus Paenibacillus. The 16S rRNA gene sequence of GW78T revealed 98.3 % similarity to its nearest neighbour Paenibacillus mucilaginosus VKPM B-7519T. Its chemotaxonomic properties included MK-7 as the sole menaquinone, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylmonomethylethanolamine and phosphatidylethanolamine as major polar lipids, and anteiso-C15 : 0, C16 : 1 ω11c and anteiso-C17 : 0 as predominant fatty acids. Digital DNA-DNA hybridization and average nucleotide identity results with its closest relatives were <74.0 % and <14.0 %, respectively. Overall, 16S rRNA gene sequence comparisons, phylogenetic and genomic evidence, and phenotypic and chemotaxonomic data allow the differentiation of GW78T from other members of the genus Paenibacillus. Thus, we propose that strain GW78T represents a novel species of the genus Paenibacillus, with the name Paenibacillus caseinilyticus sp. nov. The type strain is GW78T (=KCTC 43430T=NBRC 116023T).

Pangenome analysis provides insights into the genetic diversity, metabolic versatility, and evolution of the genus Flavobacterium.

Members of the genus Flavobacterium are widely distributed and produce various polysaccharide-degrading enzymes. Many species in the genus have been isolated and characterized. However, few studies have focused on marine isolates or fish pathogens, and in-depth genomic analyses, particularly comparative analyses of isolates from different habitat types, are lacking. Here, we isolated 20 strains of the genus from various environments in South Korea and sequenced their full-length genomes. Combined with published sequence data, we examined genomic traits, evolution, environmental adaptation, and putative metabolic functions in total 187 genomes of isolated species in Flavobacterium categorized as marine, host-associated, and terrestrial including freshwater. A pangenome analysis revealed a correlation between genome size and coding or noncoding density. Flavobacterium spp. had high levels of diversity, allowing for novel gene repertories via recombination events. Defense-related genes only accounted for approximately 3% of predicted genes in all Flavobacterium genomes. While genes involved in metabolic pathways did not differ with respect to isolation source, there was substantial variation in genomic traits; in particular, the abundances of tRNAs and rRNAs were higher in the host-associdated group than in other groups. One genome in the host-associated group contained a Microviridae prophage closely related to an enterobacteria phage. The proteorhodopsin gene was only identified in four terrestrial strains isolated for this study. Furthermore, recombination events clearly influenced genomic diversity and may contribute to the response to environmental stress. These findings shed light on the high genetic variation in Flavobacterium and functional roles in diverse ecosystems as a result of their metabolic versatility. IMPORTANCE The genus Flavobacterium is a diverse group of bacteria that are found in a variety of environments. While most species of this genus are harmless and utilize organic substrates such as proteins and polysaccharides, some members may play a significant role in the cycling for organic substances within their environments. Nevertheless, little is known about the genomic dynamics and/or metabolic capacity of Flavobacterium. Here, we found that Flavobacterium species may have an open pangenome, containing a variety of diverse and novel gene repertoires. Intriguingly, we discovered that one genome (classified into host-associated group) contained a Microviridae prophage closely related to that of enterobacteria. Proteorhodopsin may be expressed under conditions of light or oxygen pressure in some strains isolated for this study. Our findings significantly contribute to the understanding of the members of the genus Flavobacterium diversity exploration and will provide a framework for the way for future ecological characterizations.

Genomic insights and comparative analysis of Flavobacterium bizetiae HJ-32-4 isolated from soil.

In the late 1970s, Flavobacterium bizetiae was first isolated from diseased fish in Canada. After four decades of preservation, it was reported as a novel species in 2020. Here, we report the first complete genome sequence of HJ-32-4, a novel strain of F. bizetiae. Interestingly, HJ-32-4 was isolated from soil in Gangwon-do, Republic of Korea, unlike the other two previously reported F. bizetiae strains which were isolated from fish. We generated a single circular chromosome of HJ-32-4, comprising 5,745,280 bp with a GC content of 34.2%. The average nucleotide identity (ANI) value of 96.2% indicated that HJ-32-4 belongs to F. bizetiae CIP 105534T. The virulence factor was not detected in the genome. Comparative genomic analysis of F. bizetiae and major flavobacterial pathogens revealed that F. bizetiae had a larger genome size and the ratio of peptidases (PEP) and glycoside hydrolase (GH) genes of F. bizetiae were lower than those of the rest strains, implying that F. bizetiae exhibits similar characteristics with non-pathogenic strains from a genomic point of view. However, further experimental verification is required to ensure these in silico predictions. This study will provide insight into the overall characteristics of HJ-32-4 compared to other strains.

The Role of Flavobacterium enshiense R6S-5-6 in the Wetland Ecosystem Revealed by Whole-Genome Analysis.

The wetland is an important ecosystem for purifying pollutants and circulating nutrients. Numerous microorganisms contribute to maintaining this function. We obtained Flavobacterium enshiense R6S-5-6 which was isolated from Ungok (Ramsar) Wetland and conducted whole-genome sequencing to investigate what contribution R6S-5-6 could make to the wetland community. The complete genome sequence of R6S-5-6 has a size of 3,251,289 bp with 37.68% of GC content. Gene annotation revealed that R6S-5-6 has several pathways to break down pollutants, including denitrification, assimilatory sulfate reduction (ASR), and polyphosphate-accumulating process. Furthermore, R6S-5-6 has genes that can have a positive effect on plants living in wetlands, such as storing essential nutrients, promoting plant growth, and protecting plants against pathogens.

Isolation and Characterization of Thermophilic Bacteria from Hot Springs in Republic of Korea.

Thermophiles that produce extracellular hydrolases are of great importance due to their applications in various industries. Thermophilic enzymes are of interest for industrial applications due to their compatibility with industrial processes, and the availability of the organisms is essential to develop their full potential. In this study, a culture-dependent approach was used to identify thermophilic bacteria from five hot springs in Republic of Korea. Characterization, taxonomic identification, and extracellular hydrolase (amylase, lipase, and protease) activity of 29 thermophilic bacterial isolates from the Neungam carbonate, Mungang sulfur, Deokgu, Baegam, and Dongnae hot springs were investigated. Identification based on the full-length 16S rRNA gene sequence revealed that strains belonged to the phylum Bacillota and were classified as Aeribacillus, Bacillus, Caldibacillus, Geobacillus, and Thermoactinomyces genera. It was found that 22 isolates could produce at least one extracellular enzyme. Geobacillus, representing 41.4% of the isolates, was the most abundant. The highest amount of proteolytic and lipolytic enzymes was secreted by strains of the genus Geobacillus, whereas Caldibacillus species produced the highest amount of amylolytic enzyme. The Geobacillus species producing hydrolytic extracellular enzymes appeared to be the most promising.

Description of Microbacterium neungamense sp. nov. isolated from a hot spring.

The Gram-positive, nonmotile, rod-shaped bacterium EF45044T was isolated from a hot spring in Chungju, South Korea. The strain was able to grow at concentrations of 0‒5% (w/v) NaCl, at pH 6.0‒10.0 and in the temperature range of 18‒50 °C. Strain EF45044T showed the highest 16S rRNA gene sequence similarity (98.2%) with Microbacterium ketosireducens DSM 12510T, and the digital DNA‒DNA hybridization (dDDH), average amino acid identity (AAI), and average nucleotide identity (ANI) values were all lower than the accepted species threshold. Strain EF45044T contained MK‒12 and MK‒13 as the predominant respiratory quinones and anteiso‒C17:0, anteiso‒C15:0, and iso‒C16:0 as the major fatty acids. Diphosphatidylglycerol, phosphatidylglycerol, and glycolipid were detected as the major polar lipids. The cell-wall peptidoglycan contained ornithine. The DNA G + C content was 71.4 mol%. Based on the polyphasic data, strain EF45044T (= KCTC 49703T) presents a novel species of the genus Microbacterium, for which the name Microbacterium neungamense sp. nov. is proposed.

Characteristics and adaptability of Flavobacterium panici BSSL-CR3 in tidal flat revealed by comparative genomic and enzymatic analysis.

Tidal flat microbes play an important ecological role by removing organic pollutants and providing an energy source. However, bacteria isolated from tidal flats and their genomes have been scarcely reported, making it difficult to elucidate which genes and pathways are potentially involved in the above roles. In this study, strain BSSL-CR3, the third reported species among the tidal flat Flavobacterium was analyzed using whole-genome sequencing to investigate its adaptability and functionality in tidal flats. BSSL-CR3 is comprised of a circular chromosome of 5,972,859 bp with a GC content of 33.84%. Genome annotation and API ZYM results showed that BSSL-CR3 has a variety of secondary metabolic gene clusters and enzyme activities including α-galactosidase. BSSL-CR3 had more proteins with a low isoelectric point (pI) than terrestrial Flavobacterium strains, and several genes related to osmotic regulation were found in the genomic island (GI). Comparative genomic analysis with other tidal flat bacteria also revealed that BSSL-CR3 had the largest number of genes encoding Carbohydrate Active EnZymes (CAZymes) which are related to algae degradation. This study will provide insight into the adaptability of BSSL-CR3 to the tidal flats and contribute to facilitating future comparative analysis of bacteria in tidal flats.

Sulfitobacter albidus sp. nov., isolated from marine sediment of Jeju Island.

Strain JK7-1T isolated from marine sediment collected from Jeju Island of South Korea was strictly aerobic, Gram-stain-negative, catalase-positive, oxidase-positive, motile, and rod-shaped bacterium that is circular and convex with white pigment. Strain JK7-1T could grow at 10-30 °C and pH 6-9 with 1-6% (w/v) NaCl. Phylogenetic analysis based on its 16S rRNA gene sequence indicated that strain JK7-1T belonged to genus Sulfitobacter, sharing high sequence similarities with Sulfitobacter undariae W-BA2T (97.90%), Sulfitobacter donghicola KCTC 12864T (97.61%), and Sulfitobacter mediterraneus KCTC 32188T (97.47%). Strain JK7-1T possessed only ubiquinone-10 (Q-10) as a sole respiratory quinone and summed feature 8 as the major fatty acid (81.02%). A dominant polar lipid phosphatidylglycerol was identified in strain JK7-1T. Strain JK7-1T had a complete genome of 3,441,674 bp in length with a mean G + C content of 63.96%. Polyphasic and genomic analyses revealed that strain JK7-1T represented a novel species in the genus Sulfitobacter, for which a name of Sulfitobacter albidus sp. nov. was proposed. Its type strain is JK7-1T (= KCTC 72819T = NBRC 114632T = KMM 6821T).

Complete Genome Sequence of Flavobacterium sediminilitoris YSM-43T, Isolated from Tidal Sediment in Yeosu.

Here, we report the complete genome sequence of Flavobacterium sediminilitoris YSM-43T, isolated from a tidal flat in Yeosu, Republic of Korea. The whole genome consists of one circular chromosome of 3,913,692 bp. A total of 3,599 genes were predicted, comprising 3,537 coding DNA sequences (CDSs), 50 tRNAs, 9 rRNAs, and 3 noncoding RNAs (ncRNAs).

Fictibacillus marinisediminis sp. nov., a nitrate-reducing bacterium isolated from marine sediment in Hupo Basin, Republic of Korea.

An isolate, designated strain KIGAM418T was isolated from marine mud below 192 m depth in the Hupo Basin, Republic of Korea. Strain KIGAM418T was Gram-stain positive, spore-forming, rod-shaped, facultatively anaerobic, and grew at 10‒45 °C, in 0‒2% (w/v) NaCl at pH 4.0‒12.0. The strain tested positive for catalase, oxidase, and motility. Phylogenetic analysis of the 16S rRNA gene sequence indicated that strain KIGAM418T was related to the genus Fictibacillus. The strain showed the highest similarity to Fictibacillus rigui WPCB074T (98.0-98.1%) and Fictibacillus solisalsi YC1T (97.2-97.8%). The diagnostic diamino acid of the cell wall was meso-diaminopimelic acid. The major fatty acids were characterized as anteiso-C15:0 and iso-C15:0. Strain KIGAM418T possessed diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine as the major polar lipids and menaquinone-7 as the predominant menaquinone. The genome size and G + C content were 4.56 Mb and 43.2 mol%, respectively. According to predicted functional genes of the genome, the category of amino acid transport and metabolism was mainly distributed. Based on the polyphasic taxonomic data, strain KIGAM418T represents a novel species of the genus Fictibacillus, for which the name Fictibacillus marinisediminis sp. nov. is proposed. The type strain is KIGAM418T (= KCTC 43291 T = JCM 34437 T).

Complete genome sequence of marine photoheterotophic bacterium Erythrobacter sp. JK5.

Erythrobacter sp. JK5, a marine heterotrophic bacterium, was isolated from marine sediment in Jeju island, the Republic of Korea. Here, we report information on the complete genome of strain JK5, including a putative capability for photosynthesis. The genome of JK5 consisted of 3.34 Mbp with 64.2% G + C content, and contained 3210 protein-coding sequences and three rRNA genes. Genomic analysis revealed that strain JK5 might be grown under oxic, microoxic, or anoxic conditions using two types of terminal oxidase (high and low oxygen affinity) or nitrate reductase. The types IV and VI secretion systems presented in strain JK5 genome might reveal a survival advantage against their ecological competitors in the marine environment.

Genomic and Physiological Characterization of Metabacillus flavus sp. nov., a Novel Carotenoid-Producing Bacilli Isolated from Korean Marine Mud.

The newly isolated strain KIGAM252T was found to be facultatively anaerobic, Gram-stain-positive, spore-forming, and rod-shaped. They grew at 10-45 °C, pH 6.0-10.0, and were able to tolerate up to 6% NaCl in the growth medium. Phylogenetic analysis indicated that the KIGAM252T strain was related to the genus Metabacillus. The cell membrane fatty acid composition of strain KIGAM252T included C15:0 anteiso and C15:0 iso (25.6%) as the major fatty acids, and menaquinone 7 was the predominant isoprenoid quinone. The major polar lipids were diphosphatidylglycerol and phosphatidylglycerol. The size of the whole genome was 4.30 Mbp, and the G + C content of the DNA was 43.8%. Average nucleotide and amino acid identity and in silico DNA-DNA hybridization values were below the species delineation threshold. Pan-genomic analysis revealed that 15.8% of all genes present in strain KIGAM252T was unique to the strain. The analysis of the secondary biosynthetic pathway predicted the carotenoid synthetic gene cluster in the strain KIGAM252T. Based on these current polyphasic taxonomic data, strain KIGAM252T represents a novel species of the genus Metabacillus that produces carotenoids, for which we propose the name Metabacillus flavus sp. nov. The type of strain was KIGAM252T (=KCTC 43261T = JCM 34406T).

Haloferax litoreum sp. nov., Haloferax marinisediminis sp. nov., and Haloferax marinum sp. nov., low salt-tolerant haloarchaea isolated from seawater and sediment.

Three novel halophilic archaea were isolated from seawater and sediment near Yeoungheungdo Island, Republic of Korea. The genome size and G + C content of the isolates MBLA0076T, MBLA0077T, and MBLA0078T were 3.56, 3.48, and 3.48 Mb and 61.7, 60.8, and 61.1 mol%, respectively. The three strains shared 98.5-99.5 % sequence similarity of the 16 S rRNA gene, whereas their sequence similarity to the 16 S rRNA gene of type strains was below 98.5 %. Phylogenetic analysis based on sequences of the 16 S rRNA and RNA polymerase subunit beta genes indicated that the isolates belonged to the genus Haloferax. The orthologous average nucleotide identity, average amino-acid identity, and in silico DNA-DNA hybridization values were below species delineation thresholds. Pan-genomic analysis indicated that the three novel strains and 11 reference strains had 8981 pan-orthologous groups in total. Fourteen Haloferax strains shared 1766 core pan-genome orthologous groups, which were mainly related to amino acid transport and metabolism. Cells of the three isolates were gram-negative, motile, red-pink pigmented, and pleomorphic. The strains grew optimally at 30 °C (MBLA0076T) and 40 °C (MBLA0077T, MBLA0078T) in the presence of 1.28 M (MBLA0077T) and 1.7 M (MBLA0076T, MBLA0078T) NaCl and 0.1 M (MBLA0077T), 0.2 M (MBLA0076T), and 0.3 M (MBLA0078T) MgCl2·6H2O at pH 7.0-8.0. Cells of all isolates lysed in distilled water; the minimum NaCl concentration necessary to prevent lysis was 0.43 M. The major polar lipids of the three strains were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, and sulphated diglycosyl archaeol-1. Based on their phenotypic and genotypic properties, MBLA0076T, MBLA0077T, and MBLA0078T were described as novel species of Haloferax, for which we propose the names Haloferax litoreum sp. nov., Haloferax marinisediminis sp. nov., and Haloferax marinum sp. nov., respectively. The respective type strains of these species are MBLA0076T (= KCTC 4288T = JCM 34,169T), MBLA0077T (= KCTC 4289T = JCM 34,170T), and MBLA0078T (= KCTC 4290T = JCM 34,171T).

Hymenobacter guriensis sp. nov., and Hymenobacter duratus sp. nov., Radiation-Resistant Species Isolated from Soil in South Korea.

Two novel Gram-stain-negative, non-motile, aerobic, rod-shaped, circular, convex, red-colored and UV-tolerant strains BT594T and BT646T were isolated from soil collected in Guri city (37° 36' 0″ N, 127° 9' 0″ E) and Gwangju city (37° 22' 0″ N, 127° 17' 0″ E), respectively, South Korea. 16S rDNA sequence analysis indicated that strains BT594T and BT646T belong to a distinct lineage within the genus Hymenobacter (family Hymenobacteraceae, order Cytophagales, class Cytophagia, phylum Bacteroidetes, kingdom Bacteria). The 16S rDNA gene sequence similarity between the two strains BT594T and BT646T was 96.2%. The strain BT594T was closely related to Hymenobacter psychrotolerans Tibet-IIU11T (97.0% 16S rDNA gene similarity) and Hymenobacter tibetensis XTM003T (96.3%). The strain BT646T was closely related to Hymenobacter psychrotolerans Tibet-IIU11T (98.6%), Hymenobacter kanuolensis T-3 T (96.8%) and Hymenobacter perfusus LMG 26000 T (96.7%). The two strains were found to have the same quinone system, with MK-7 as the major respiratory quinone. The major polar lipids of strains BT594T and BT646T were phosphatidylethanolamine (PE) and aminophospholipids (APL). The major cellular fatty acids of strain BT594T were anteiso-C15:0 (17.9%), iso-C15:0 (16.1%) and summed feature 3 (C16:1 ω6c / C16:1 ω7c) (10.0%). The major cellular fatty acids of strain BT646T were summed feature 3 (C16:1 ω6c / C16:1 ω7c) (18.3%), C16:0 (17.2%) and summed feature 4 (iso-C17:1 I / anteiso-C17:1 B) (14.5%). Based on the polyphasic analysis, strains BT594T and BT646T can be suggested as two novel bacterial species within the genus Hymenobacter and the proposed names are Hymenobacter guriensis and Hymenobacter duratus, respectively. The type strain of Hymenobacter guriensis is BT594T (= KCTC 21863 T = NBRC 114853 T) and the type strain of Hymenobacter duratus is BT646T (= KCTC 21915 T = NBRC 114854 T).

Salinimonas marina sp. nov. Isolated from Jeju Island Marine Sediment.

A Gram-stain-negative, rod-shaped, and strictly aerobic bacterium designated strain G2-bT was isolated from the marine sediment around Jeju Island, South Korea. Strain G2-bT was found to be catalase- and oxidase-positive, white-pigmented, motile with polar flagellum, and to grow optimally at 25 °C, pH 7.0 in the presence of 4% (w/v) NaCl. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that strain G2-bT belongs to the genus Salinimonas and was closely related Salinimonas sediminis N102T (96.7% sequence similarity), Salinimonas iocasae KX18D6T (95.4%), Salinimonas lutimaris DPSR-4T (94.7%), and Salinimonas chungwhensis BH030046T (94.6%). Strain G2-bT possessed ubiquinone 8 as the sole respiratory quinone, summed feature 3 and summed feature 8 as the major fatty acids, and phosphatidylethanolamine and phosphatidylglycerol as the major polar lipids. The genome size and G + C content of the strain G2-bT were determined to be 3,765,169 bp, and 49.7%, respectively, as a complete circular genome. Based on the genomic analyses (e.g., average nucleotide identity and digital DNA-DNA hybridization), the strain G2-BT likely represents a new species in the genus Salinimonas, for which we propose to name this novel bacterium Salinimonas marina sp. nov., and the type strain is designated G2-BT (= KCTC 72817T = VTCC 910110T).

Parasphingorhabdus halotolerans sp. nov. isolated from marine sediment in Jeju Island.

A Gram-stain-negative, catalase- and oxidase-positive, rod-shaped bacterium, designated as JK6T was isolated from a coastal marine sediment in Jeju Island. Strain JK6T was characterized by polyphasic investigation including genome features. It grew at pH 5.0-9.0 (optimum 7.5), 18-30 °C (optimum 25 °C) and 1.0-7.0% (w/v) NaCl (optimum 2.0%). Strain JK6T utilized D-mannose, D-glucose, L-fucose, propionate and acetate as carbon and energy sources. The sole quinone was ubiquinone-10, and the major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, and sphingolipid. Strain JK6T was closely related to Parasphingorhabdus flavimaris SW-151T (98.2%), Parasphingorhabdus marina DSM 22363T (97.6%) and Parasphingorhabdus litoris FR1093T (97.6%) based on 16S rRNA gene sequence similarity. Genome length and GC content were 3.29 Mbp and 53.0%, respectively. Digital DNA-DNA relatedness, average nucleotide identity, and average amino acid identity between strain JK6T and P. flavimaris SW-151T were 16.6%, 73.9%, and 77.6%, respectively. These results showed that the strain can be recognized as a novel bacterium named Parasphingorhabdus halotolerans. The type strain of Parasphingorhabdus halotolerans sp. nov. is JK6T (= KCTC 72818T = VTCC 910111T).

Flavobacterium inviolabile sp. nov. isolated from stream water.

A Gram-stain-negative, rod-shaped, aerobic and non-motile bacterium, designated P2-65T, was isolated from Moonsan stream water in the Republic of Korea. The temperature, NaCl concentration and pH ranges for growth of strain P2-65T were 10-37 °C, 0.0-3.0% (w/v) and 6.5-8.5 with optimum growth at 25-30 °C, 0.0-1.0% and 7.0-7.5, respectively. Comparison of 16S rRNA gene sequence showed that strain P2-65T was closely related to Flavobacterium cauense (95.4%) and Flavobacterium cheniae (95.3%). The major fatty acids were iso-C15:0, iso C17:0 3-OH, summed feature 3 (C16:1ω7c and/or C16:1ω6c), summed feature 9 (iso-C17:1 ω9c and/or 10-methyl C16:0) and iso-C15:0 3-OH. The predominant respiratory quinone was menaquinone-6 (MK-6). The major polar lipids detected in the strain were phosphatidylethanolamine, one aminophospholipid, one unidentified aminolipid and one unidentified polar lipid. The G + C content of the genomic DNA was 39.7%. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values for strain P2-65T with closely related Flavobacterium species were below 74.8% and 20%, respectively. Based on polyphasic features, strain P2-65T is considered to represent a novel species of the genus Flavobacterium, for which the name Flavobacterium inviolabile sp. nov. is proposed. The type strain is P2-65T (= KCTC 62055T = NBRC 112953T).

Draconibacterium halophilum sp. nov., A Halophilic Bacterium Isolated from Marine Sediment.

A Gram-stain-negative, long-rod shaped, and facultatively anaerobic bacterium, designated as strain M1T, was isolated from the marine sediment of Jeju Island, South Korea. Strain M1T was found to be catalase- and oxidase-positive, light yellow-pigmented, non-motile, and non-flagellated, growing optimally at 30 °C, pH 7.0, and in the presence of 3% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain M1T belongs to the genus Draconibacterium and is closely related to Draconibacterium orientale FH5T (97.2%), Draconibacterium sediminis JN14CK-3 T (96.5%), "Draconibacterium filum" F2T (96.5%) and Draconibacterium mangrovi GM2-18 T (96.3% sequence similarity). The values for digital DNA-DNA hybridization ranged from 37.6 to 38.3% against D. orientale FH5T, D. sediminis KN14CK-3 T, and D. mangrovi GM2-18 T, clearly indicating that strain M1T represents a distinct species of the genus Draconibacterium. Strain M1T has a 40.0% G + C content estimated by genome sequence, menaquinone 7 as the sole respiratory quinone, C15:0 anteiso and C15:0 iso as the major fatty acids, and phosphatidylethanolamine, an unidentified phospholipid, and unidentified lipids as the polar lipids. Based on the polyphasic characteristics, it is suggested that strain M1T be assigned to the genus Draconibacterium as the type strain of a novel species, for which the name Draconibacterium halophilum sp. nov. is proposed. The type strain is M1T (= KCTC 72809 T = VTCC 910107 T).