Description of Pseudomarimonas salicorniae sp. nov., Isolated from Salicornia herbacea L. in the Tidal Flat of the Yellow Sea.

A Gram-stain-negative, strictly aerobic, non-motile, rod-shaped, designated strain CAU 1642 T, was isolated from a Salicornia herbacea collected from a tidal flat in the Yellow Sea. Strain CAU 1642 T grew optimally at pH 8.0 and 30 °C. The highest 16S rRNA gene sequence similarity was 97.25%, with Pseudomarinomonas arenosa CAU 1598 T, and phylogenetic analysis indicated that strain CAU 1642 T belongs to the genus Pseudomarinomonas. The major cellular fatty acids were iso-C15:0, iso-C16:0, and summed feature 9 (iso-C17:1ω9c and/or 10-methyl C16:0). Ubiquinone-8 was the major respiratory quinone. The draft genome of strain CAU 1642 T was 4.5 Mb, with 68.7 mol% of G + C content. The phylogenetic, phenotypic, and chemotaxonomic analysis data reveal strain CAU 1642 T to be of a novel genus in the family Lysobacteraceae, with the proposed name Pseudomarinomonas salicorniae sp. nov. with type strain CAU 1642 T (= KCTC 92084 T = MCCC 1K07085T).

Aquibaculum arenosum gen. nov., sp. nov., a novel member of the family Rhodovibrionaceae, isolated from sea sand.

A Gram-negative, non-motile, and creamy-white coloured bacterium, designated CAU 1616T, was isolated from sea sand collected at Ayajin Beach, Goseong-gun, Republic of Korea. The bacterium was found to grow optimally at 37 °C, pH 8.0-8.5, and with 1-5 % (w/v) NaCl. Phylogenetic analyses based on the 16S rRNA gene sequences placed strain CAU 1616T within the order Rhodospirillales. The highest 16S rRNA gene sequence similarity was to Fodinicurvata fenggangensis YIM D812T (94.1 %), Fodinicurvata sediminis YIM D82T (93.7 %), Fodinicurvata halophila BA45ALT (93.6 %) and Algihabitans albus HHTR 118T (92.3 %). Comparing strain CAU 1616T with closely related species (Fodinicurvata fenggangensis YIM D812T and Fodinicurvata sediminis YIM D82T), the average nucleotide identity based on blast+ values were 69.7-69.8 %, the average amino acid identity values were 61.3-61.4 %, and the digital DNA-DNA hybridization values were 18.4-18.5 %. The assembled draft genome of strain CAU 1616T had 29 contigs with an N50 value of 385.8 kbp, a total length of 3 490 371 bp, and a DNA G+C content of 65.1 mol%. The predominant cellular fatty acids were C18 : 1 2-OH, C19 : 0 cyclo ω8c, and summed feature 8 (C18 : 1 ω6c and/or C18 : 1 ω7c). The major respiratory quinone was Q-10. Based on phenotypic, phylogenetic, and chemotaxonomic evidence, strain CAU 1616T represents a novel genus in the family Rhodovibrionaceae, for which the name Aquibaculum arenosum gen. nov., sp. nov. is proposed. The type strain is CAU 1616T (=KCTC 82428T=MCCC 1K06089T).

Description of Roseibium sediminicola sp. nov. Isolated from Sediment of a Tidal Flat on the Yellow Sea Coast.

A Gram-stain-negative, aerobic, rod-shaped, motile, flagellated bacterial strain, designated as CAU 1639T, was isolated from the tidal flat sediment on the Yellow Sea in the Republic of Korea. Growth of the isolate was observed at 20-37 °C, at pH 5.0-10.5 and with 0-7% (w/v) NaCl. The genomic DNA G + C content was 60.8%. Phylogenetic analysis, grounded on 16S rRNA gene sequencing, revealed that strain CAU 1639T was closely related to species within the genus Roseibium. It shared the highest similarity with Roseibium album CECT 5095T, followed by Roseibium aggregatum IAM 12614T and Roseibium salinum Cs25T, with 16S rRNA gene sequence similarity ranging from 98.0-98.4%. It was observed that the average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values ranged between 72.5-79.5 and 20.0-22.9%, respectively. The polyphasic taxonomic analysis reveals that strain CAU 1639T represents a novel species in the genus Roseibium with the proposed name Roseibium sediminicola sp. nov. The type strain is CAU 1639T (= KCTC 82430T = MCCC 1K06081T).

Description of Mycolicibacterium arenosum sp. nov. Isolated from Coastal Sand on the Yellow Sea Coast.

A Gram-staining-positive, aerobic, non-spore-forming bacterium was isolated from coastal sand samples from Incheon in the Republic of Korea and designated as strain CAU 1645T. The optimum conditions for growth were observed at 30 °C in growth media containing 1% (w/v) NaCl at pH 9.0. The predominant respiratory quinone was MK-9 and the major fatty acids were C16:0, C17:1 w7c, and summed feature 7. Similarly, the 16S rRNA gene sequence exhibited the highest similarity with Mycolicibacterium bacteremicum DSM 45578T and Mycolicibacterium neoaurum JCM 6365T, both of which exhibited similarity rates of 97.2%. The genomic DNA G+C content was 68.2%. The whole genome of strain CAU 1645T was obtained and annotated with annotation using RAST server. The pan-genome analysis was determined using Prokka, Roary, and Phandango. In the pan-genome analysis, the strain CAU 1645T shared 40 core genes with closely related Mycolicibacterium species, including the AcpM gene, the meromycolate extension acyl carrier protein involved in forming impermeable cell walls in mycobacteria. Therefore, our findings demonstrated that the isolate represents a novel species of the genus Mycolicibacterium, for which we propose the name Mycolicibacterium arenosum sp. nov. The type strain is CAU 1645T (= KCTC 49724T = MCCC 1K07087T).

Genomic insight into Algoriphagus limi sp. nov. isolated from a mudflat on the Yellow Sea coast.

A Gram-negative, non-motile, and reddish-orange colored bacterium, designated CAU 1643T, was isolated from a mudflat collected in Ganghwa Island, Republic of Korea. The bacterium was found to grow optimally at 30°C, pH 9.0-9.5, and with 0%-1% (w/v) NaCl. The highest 16S rRNA gene sequence similarities to the bacterium were Algoriphagus kandeliae XY-J91T (97.9%), A. aquimaris F21T (97.1%), A. formosus XAY3209T (97.0%), and A. marincola DSM 16067T (96.2%). The DNA G + C content of the type strain was 40.35 mol%. The average nucleotide identity and digital DNA-DNA hybridization values between strain CAU 1643T and the reference strains were below the threshold value for species demarcation. The predominant cellular fatty acids were iso-C15:0, iso-C17:0 3-OH, and Summed Feature 9. The major respiratory quinone was menaquinone-7. The genome showed three putative biosynthetic gene clusters that are responsible for different secondary metabolites. Moreover, CAU 1643T contains 72 genes that encode carbohydrate-active enzymes. Based on phenotypic, phylogenetic, and chemotaxonomic evidence, strain CAU 1643T represents novel species in the genus Algoriphagus, for which the name A. limi sp. nov. is proposed. The type strain is CAU 1643T ( = KCTC 92080T, = MCCC 1K07150T).

Gracilimonas sediminicola sp. nov., a moderately halotolerant bacterium isolated from seaweed sediment collected in the East Sea, Republic of Korea.

A Gram-stain-negative, aerobic, rod-shaped bacterium, designated as strain CAU 1638T, was isolated from seaweed sediment collected in the Republic of Korea. The cells of strain CAU 1638T grew at 25-37 °C (optimum, 30 °C), at pH 6.0-7.0 (optimum, pH 6.5) and in the presence of 0-10% NaCl (optimum, 2 %). The cells were positive for catalase and oxidase and did not hydrolyse starch and casein. Strain CAU 1638T was most closely related to Gracilimonas amylolytica KCTC 52885T (97.7 %), followed by Gracilimonas halophila KCTC 52042T (97.4 %), Gracilimonas rosea KCCM 90206T (97.2 %), Gracilimonas tropica KCCM 90063T and Gracilimonas mengyeensis DSM 21985T (97.1 %), as revealed by 16S rRNA gene sequencing. MK-7 was the major isoprenoid quinone, and iso-C15  : 0 and C15  : 1 ω6c were the major fatty acids. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, two unidentified lipids, two unidentified glycolipids and three unidentified phospholipids. The G+C content of the genome was 44.2 mol%. The average nucleotide identity and digital DNA-DNA hybridization values between strain CAU 1638T and the reference strains were 73.1-73.9 % and 18.9-21.5  %, respectively. Based on its phylogenetic, phenotypic and chemotaxonomic features, strain CAU 1638T represents a novel species of the genus Gracilimonas, for which the name Gracilimonas sediminicola sp. nov. is proposed. The type strain is CAU 1638T (=KCTC 82454T=MCCC 1K06087T).

Description of Defluviimonas salinarum sp. nov. with the potential of benzene-degradation isolated from saltern in the Yellow Seacoast.

Strain CAU 1641T was isolated from saltern collected in Ganghwa Island, Republic of Korea. The bacterium was an aerobic, Gram-negative, catalase-positive, oxidase-positive, motile, and rod-shaped bacterium. Cell of strain CAU 1641T could grow at 20-40°C and pH 6.0-9.0 with 1.0-3.0% (w/v) NaCl. Stain CAU 1641T shared high 16S rRNA gene sequence similarities with Defluviimonas aquaemixtae KCTC 42108T (98.0%), Defluviimonas denitrificans DSM 18921T (97.6%), and Defluviimonas aestuarii KACC 16442T (97.5%). Phylogenetic trees based on the 16S rRNA gene and the core-genome sequences indicated that strain CAU 1641T belonged to genus Defluviimonas. Strain CAU 1641T contained ubiquinone-10 (Q-10) as the sole respiratory quinone and and summed feature 8 (C18:1ω6c and/or C18:1ω7c) as the predominant fatty acid (86.1%). The pan-genome analysis indicated that the genomes of the strain CAU 1641T and 15 reference strains contain a small core genome. The Average Nucleotide Identity and digital DNA-DNA hybridization values among strain CAU 1641T and reference strains of the genus Defluviimonas were in the range of 77.6%-78.8% and 21.1-22.1%, respectively. The genome of strain CAU 1641T has several genes of benzene degradation. The genomic G + C content was 66.6%. Based on polyphasic and genomic analyses, strain CAU 1641T represents a novel species of the genus Defluviimonas, for which the name Defluviimonas salinarum sp. nov., is proposed. The type strain is CAU 1641T ( = KCTC 92081T = MCCC 1K07180T).

Characterization of a Potential Probiotic Lactiplantibacillus plantarum LRCC5310 by Comparative Genomic Analysis and its Vitamin B6 Production Ability.

Safety assessment and functional analysis of probiotic candidates are important for their industrial applications. Lactiplantibacillus plantarum is one of the most widely recognized probiotic strains. In this study we aimed to determine the functional genes of L. plantarum LRCC5310, isolated from kimchi, using next-generation, whole-genome sequencing analysis. Genes were annotated using the Rapid Annotations using Subsystems Technology (RAST) server and the National Center for Biotechnology Information (NCBI) pipelines to establish the strain's probiotic potential. Phylogenetic analysis of L. plantarum LRCC5310 and related strains showed that LRCC5310 belonged to L. plantarum. However, comparative analysis revealed genetic differences between L. plantarum strains. Carbon metabolic pathway analysis based on the Kyoto Encyclopedia of Genes and Genomes database showed that L. plantarum LRCC5310 is a homofermentative bacterium. Furthermore, gene annotation results indicated that the L. plantarum LRCC5310 genome encodes an almost complete vitamin B6 biosynthetic pathway. Among five L. plantarum strains, including L. plantarum ATCC 14917T, L. plantarum LRCC5310 detected the highest concentration of pyridoxal 5'-phosphate with 88.08 ± 0.67 nM in MRS broth. These results indicated that L. plantarum LRCC5310 could be used as a functional probiotic for vitamin B6 supplementation.

Exopolymeric substance from Bacillus velezensis P1 as an antifungal additive in chitosan coating to prolong the shelf life of mangoes.

Bacillus velezensis P1 inhibits various phytopathogenic fungi. Its exopolymeric substance (EPS) was active against Colletotrichum sp. at a minimum inhibitory concentration (MIC) of 6.25 mg/ml. EPS was added to chitosan from squid pen to produce an antifungal film coating. The addition of EPS at its MIC had no effect on the color of the chitosan film. Two components showed good compatibility and the tensile strength of the film was higher than that of neat chitosan film. Mangoes were treated with six different coatings, including the two films. Fruits coated with the films showed the lowest weight loss and prolonged shelf life of mangoes to three times the shelf life of controls (water and 2 % citric acid, w/v) and completely inhibited fungal infection. Film coatings of chitosan, alone or combined with the EPS from B. velezensis P1, showed potential to prolong the shelf life of ripe mangoes and decrease postharvest losses.

Zhongshania aquimaris sp. nov., isolated from seawater.

A Gram-negative, motile, rod-shaped, aerobic bacterial strain CAU 1632T was isolated from a seawater sample collected in the Republic of Korea. The cells of strain CAU 1632T grew optimally at 30 °C and pH 7.0 in 0% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain CAU 1632T formed a tight phyletic lineage with Zhongshania antarctica ZS-23T, Zhongshania borealis CL-AS9T, Zhongshania marina DSW25-10T, Zhongshania guokunii ZS6-22T, 'Zhongshania ponticola GM-8T', Zhongshania aliphaticivorans SM-2T and shared a high similarity between 97.2% and 97.7%. The whole genome of strain CAU 1632T was 4.3-Mb with 3,780 protein-coding genes, 12 contigs, and a DNA G+C content of 49.4 mol%. The major fatty acids of strain CAU 1632T were C17:1 ω8c, C19:1 ω6c and/or C19:0 cyclo ω10c (summed feature 3), and C18:1 ω6c and/or C18:1 ω7c (summed feature 8). Q-8 was the only respiratory quinone. The polar lipids were composed of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, two aminophospholipids, and two phospholipids. Based on the results of phenotypic, chemotaxonomic, and phylogenetic analyses, strain CAU 1632T represents a novel species within the genus Zhongshania, for which the name Zhongshania aquimaris sp. nov. is proposed. The type strain is CAU 1632T (= KCTC 82432T = MCCC 1K06086T).

Muricauda lutisoli sp. nov., isolated from mudflat.

A Gram-negative, nonmotile, rod-shaped bacterium, designated strain CAU 1631T, was isolated from a mudflat sample in the Republic of Korea. Strain CAU 1631T grew optimally at 30 °C, pH 6.5, and 1% (w/v) NaCl solution. Phylogenetic analysis based on 16S rRNA gene sequencing and 92 core genes indicated that strain CAU 1631T is a member of the genus Muricauda and most closely related to Muricauda oceanensis 40DY170T and Muricauda lutimaris SMK-108T (98.1%, both). The draft genome was 3.4 Mb with 3064 protein-coding genes, and the DNA G + C content was 43.3 mol%. The major fatty acids were iso-C15:0, iso-C17:0 3-OH, and iso-C15:0 G, and the major polar lipid was phosphatidylethanolamine. The predominant respiratory quinone was MK-6. Based on the comprehensive taxonomic characterization, strain CAU 1631T is a novel species, for which the name Muricauda lutisoli sp. nov. has been proposed. The type strain is CAU 1631T (= KCTC 82456T = MCCC 1K06088T).

Halomarinibacterium sedimenti gen. nov., sp. nov., a carotenoid pigment-producing bacterium isolated from marine sediment.

A Gram-negative, strictly aerobic, non-motile, rod-shaped bacterial strain CAU 1614T was isolated from a marine sediment sample collected in the Republic of Korea. Optimal growth of strain CAU 1614T proceeded at 30 °C, pH 7.0, and 2% (w/v) NaCl. 16S rRNA gene similarity was lower than 94.5% with genera Aureisphaera, Marinirhabdus, Aureitalea, Gilvibacter, Ulvibacter, and Jejudonia. The highest similarity was with Aureisphaera galaxeae 04OKA003-7T (94.5%). The major cellular fatty acids were iso-C15:0, iso-C16:0, iso-C15:1 G, iso-C16:0 3-OH, and iso-C17:0 3-OH and the predominant menaquinone was MK-6. The polar lipids were phosphatidylethanolamine, phosphoglycolipid, an unidentified lipid, two unidentified aminolipids, and an unidentified glycolipid. The draft genome of strain CAU 1614T was 3.9 Mb and DNA G+C content was 36.0 mol%. On the basis of the phenotypic, chemotaxonomic, and genomic data, strain CAU 1614T presents a novel genus in the family Flavobacteriaceae, for which the name Halomarinibacterium sedimenti gen. nov., sp. nov. is proposed. The type strain is CAU 1614T (= KCTC 82457T = MCCC 1K06083T).

Thalassococcus arenae sp. nov. isolated from sea sand.

A Gram-negative, aerobic, rod-shaped bacterium, designated strain CAU 1522T, was isolated from a sea sand sample collected from the Republic of Korea. Optimal growth of strain CAU 1522T ensued at 30 °C, pH 7.5, and 1.0% (w/v) NaCl. Strain CAU 1522T was affiliated to the genus Thalassococcus with high similarity to T. lentus KCTC 32084T (97.5%), T. profundi MCCC 1K03253T (96.5%), and T. halodurans JCM 13833T (96.1%) according to phylogenetic analysis based on 16S rRNA gene sequences. The whole genome of strain CAU 1522T was 3.7 Mb in length and included 7 contigs and 3599 protein-coding genes, with a G + C content of 65.4 mol%. The predominant cellular fatty acids were C18:1 ω6c and/or C18:1 ω7c (summed feature 8), with Q-10 being the sole isoprenoid quinone. The polar lipids included phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, phosphoglycolipid, and an unidentified lipid. These phenotypic, chemotaxonomic, and phylogenetic data support that strain CAU 1522T is a novel Thalassococcus species, for which the name T. arenae sp. nov. is proposed. The type strain is CAU 1522T (= KCTC 72545T = MCCC 1K04064T).

Thauera sedimentorum sp. nov., Isolated from Coastal Sediment.

A Gram-negative, strictly aerobic, rod-shaped, non-spore-forming bacterium, designated CAU 1555T, was isolated from a sediment sample collected on Jeju Island, Republic of Korea. Growth of the isolate was observed at 20-37 °C (optimum at 30 °C) and pH 5.5-10.0 (optimum at 8.0). Phylogenetic analysis based on the result of 16S rRNA gene sequences revealed that strain CAU 1555T belonged to the genus Thauera and was closely related to Thauera hydrothermalis GD-2T (98.4% sequence similarity), Thauera lacus D20T (96.6%), and Thauera linaloolentis 47LolT (95.5%). Strain CAU 1555T possessed phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine, one unidentified phospholipid, and one aminophospholipid as the major polar lipids; Q-8 as the predominant respiratory quinone; and C16:0, summed feature 3 (comprising C16:1ω6c and/or C16:1ω7c), and summed feature 8 (comprising C18:1 ω7c/ C18:1 ω6c) as the major fatty acids. The average nucleotide identity (ANI), average amino acid identity (AAI), and digital DNA-DNA hybridization (dDDH) values between the new isolate and T. hydrothermalis GD-2T were 84.5%, 86.4%, and 28.0%, respectively. Whole-genome sequencing of strain CAU 1555T revealed 3,955,289 bp with a DNA G + C content of 68.0 mol%. Based on the results of its polyphasic properties and genomic analysis, the isolate represents a novel species within the genus Thauera, for which the name Thauera sedimentorum sp. nov. is proposed, with CAU 1555T (= KCTC 72546T = MCCC 1K04065T) as the type strain.

Marinobacterium arenosum sp. nov., isolated from a coastal sand.

A Gram-negative, aerobic, motile, rod-shaped bacterium, designated strain CAU 1594T, was isolated from a coastal sand sample collected in the Republic of Korea. Cells of strain CAU 1594T grew best at 30 °C, pH 7.5, and in the presence of 1% (w/v) NaCl. Phylogenetic analysis, based on 16S rRNA gene sequencing, indicated that strain CAU 1594T was affiliated with the genus Marinobacterium and most similar to Marinobacterium jannaschii ATCC 27135T (95.1%) and Marinobacterium stanieri ATCC 27130T (94.9%). The whole genome of strain CAU 1594T was 4,917,683 bp, including 4,188 CDSs, with a 60.4 mol% G + C content. Based on draft genome sequences, the average nucleotide identity and digital DNA-DNA hybridization values of strain CAU 1594T were within the ranges of 71.9-73.1% and 20.0-2.1%, respectively, compared to reference strains. The major respiratory quinone was ubiquinone-8, and the major fatty acids were C16:0, summed feature 3 (C16:1 ω6c and C16:1 ω7c), and summed feature 8 (C18:1 ω6c and C18:1 ω7c). The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine. Based on these results, strain CAU 1594T represents a novel species of the genus Marinobacterium, for which the name Marinobacterium arenosum sp. nov. is proposed. The type strain is CAU 1594T (=KCTC 82405T=MCCC 1K05672T).

Sneathiella sedimenti sp. nov., isolated from marine sediment.

A novel bacterium, designated CAU 1612T, was isolated from coastal sediment sampled in the Republic of Korea. Cells of the strain were Gram-stain-negative, rod-shaped and motile. Optimum growth occurred at 30 °C, at pH 7.0 and with 1.0 % (w/v) NaCl. Based on 16S rRNA gene sequences, phylogenetic analysis revealed that strain CAU 1612T belonged to the genus Sneathiella and showed highest similarity to 'Sneathiella litorea' JCM 33810T (98.5 %), followed by Sneathiella chungangensis KCTC 32476T (97.7 %), Sneathiella aquimaris KCTC 12842T (96.0 %), Sneathiella chinensis LMG 23452T (95.5 %), Sneathiella limimaris KCTC 52846T (95.5 %) and Sneathiella glossodoripedis KCTC 12842T (95.4 %). The average nucleotide identity and digital DNA-DNA hybridization values of strain CAU 1612T were estimated to be 68.5-81.7 % and ≤23.7 %, respectively, to members of the genus Sneathiella. The DNA G+C content was 54.1 mol%. The major cellular fatty acids (>10 %) were C16:0, C19 : 0 cyclo ω8c and summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c). The major menaquinone was Q-10 and the predominant polar lipids were phosphatidylmethylethanolamine, phosphatidylethanolamine and phosphatidylglycerol. On the basis of taxonomic evidence, strain CAU 1612T represents a novel species, for which the name Sneathiella sedimenti sp. nov. is proposed. The type strain is CAU 1612T (=KCTC 82427T=MCCC 1K06082T).

Marinobacter arenosus sp. nov., a halotolerant bacterium isolated from a tidal flat.

A Gram-negative, rod-shaped, motile bacterium, designated strain CAU 1620T, was isolated from a tidal flat sediment in Incheon, Republic of Korea. Strain CAU 1620T grew optimally at 30 °C and pH 8.0 in the presence of 6.0% (w/v) NaCl. The results of 16S rRNA gene sequence analysis revealed that strain CAU 1620T showed the highest similarity to Marinobacter adhaerens DSM 23420T (98.5%), followed by Marinobacter algicola DSM 16394T (98.3%) and Marinobacter maroccanus LMG 30465T (98.2%). The average nucleotide identity and digital DNA-DNA hybridisation values between strain CAU 1620T and related strains were estimated as 75.6-78.1% and 19.5-20.9%, respectively. The DNA G + C content based on the draft genome sequence was 59.2%, and the major respiratory quinone was ubiquinone-9. The predominant cellular fatty acids were C12:0, C16:0, C18:1 ω9c, and C12:0 3OH. The predominant polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, and phosphatidylglycerol. According to phenotypic, genotypic, and chemotaxonomic analyses, strain CAU 1620T represents a novel species of the genus Marinobacter, for which the name Marinobacter arenosus sp. nov. is proposed. The type strain is CAU 1620T (= KCTC 82431T = MCCC 1K06079T).

Arenibacterium arenosum sp. nov., isolated from sea sand.

A Gram-negative, non-motile, short rod-shaped aerobic bacterial strain CAU 1593T was isolated from a coastal sand sample collected in the Republic of Korea. Cells of strain CAU 1593T grew optimally at 30 °C and pH 7.5 in 4% (w/v) NaCl. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that strain CAU 1593T had the highest similarity to Arenibacterium halophilum (97.5%). The whole genome of strain CAU 1593T was 3,979,826 bp with 26 contigs, and the DNA G + C content was 64.3 mol%. The major fatty acid of strain CAU 1593 T was summed feature 8 (C18:1 ω7c/C18:1 ω6c). Q-10 was the only respiratory quinone. The polar lipids were composed of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, two phosphoglycolipids, an unidentified glycolipid, and an unidentified lipid. Based on the results of chemotaxonomic, phylogenetic, and phenotypic analyses, strain CAU 1593T represents a novel species in the genus Arenibacterium, which is named Arenibacterium arenosum sp. nov. The type strain is CAU 1593T (= KCTC 82402T = MCCC 1K05671T).

Paenibacillus arenosi sp. nov., a siderophore-producing bacterium isolated from coastal sediment.

In this study, strain CAU 1523T, a novel Gram-positive-positive bacterium isolated from marine sediment collected from the coast of Busan, Republic of Korea, was characterized using a polyphasic taxonomic approach. This strain showed growth at a temperature range of 20-37 °C (optimum, 30 °C), a pH range of 6.5-9.5 (optimum, 7.5), and in the presence of 0-3% (w/v) NaCl (optimum, 1%). Phylogenetic analysis based on 16S rRNA gene sequencing and 92 concatenated core genes indicated that CAU 1523T belonged to the genus Paenibacillus, sharing the highest sequence similarity with P. assamensis JCM 13186T (98.0%). CAU 1523T was differentiated from other Paenibacillus species by average nucleotide identity, average amino acid identity, and digital DNA-DNA hybridization values, using cut-off values of 95-96%, 90%, and 70%, respectively, for closely related strains. The genome of CAU 1523T possessed various biosynthetic gene clusters, one of which encoded a putative siderophore-interacting protein. Siderophore production by the isolate was confirmed using the qualitative chrome azurol sulfonate (CAS) agar assay. Based on its phylogenetic and physiological characteristics, strain CAU 1523T represents a novel, siderophore-producing species within the genus Paenibacillus, for which the name Paenibacillus arenosi sp. nov. is proposed, with the type strain CAU 1523T (= KCTC 43108T = MCCC 1K04063T).

Culture optimization to enhance carotenoid production of a selected purple nonsulfur bacterium and its activity against acute hepatopancreatic necrosis disease-causing Vibrio parahaemolyticus.

Purple nonsulfur bacteria (PNSB) were investigated for their carotenoid production and anti-vibrio activity against acute hepatopancreatic necrosis disease (AHPND)-causing Vibrio parahaemolyticus. To test carotenoid production, selected strains were cultivated in basic isolation medium (BIM), glutamate acetate medium, G5 medium and artificial acetic acid wastewater (AAW) medium. From 144 PNSB, Rhodopseudomonas palustris KTSSG46 was selected to produce carotenoids under microaerobic light conditions in BIM. When the culture medium was optimized, strain KTSSG46 grown in BIM modified with l-glutamate at 1 g/L more effectively inhibited AHPND-causing V. parahaemolyticus strains than standard BIM with 1 g/L (NH4 )2 SO4 . BIM was further modified with 1.23 g/L MgSO4 ·7H2 O and carotenoid production increased 40.22%. Carotenoid production at day 2 by strain KTSSG46 grown in BIM modified with l-glutamate at 1 and 1.23 g/L MgSO4 ·7H2 O was the same as production in BIM modified with monosodium glutamate (MSG). Culture supernatants from all BIM formulations showed similar activity against the resistant AHPND strain SR2. Based on high-performance liquid chromatography, carotenoids of strain KTSSG46 might be canthaxanthin. Grown in BIM modified with MSG, strain KTSSG46 could produce inexpensive carotenoids and release anti-vibrio compounds that, applied as shrimp feed additive, would prevent AHPND strains.