Five novel bacterial strains, designated as 2210JD10-5T, 2304DJ31-5T, 2307UL18-2T, 2307ULW6-5T and 2308TA10-17T, were isolated from diverse marine samples in the Republic of Korea, including algae, sponge, coral and seawater. The five novel strains affiliated with the genus Maribacter were taxonomically characterized using a polyphasic approach. The cells were catalase- and oxidase-positive and rod-shaped. The five novel strains were revealed as mesophilic, neutrophilic in pH and slightly halophilic. The major cellular fatty acids and respiratory quinone were identified as iso-C15:0, iso-C15:1 G and iso-C17:0 3-OH and menaquinone-6 (100%), respectively. The five novel strains shared polar lipids, including phosphoethanolamine, aminoglycolipid, glycolipid and unidentified lipid. The DNA G+C content range was 37.5-50.5 mol%. Phylogenetic analyses based on 16S rRNA gene and whole-genome sequences consistently formed distinct phylogenetic lineages within the genus Maribacter. The average nucleotide identity (67.7-80.9%) and digital DNA-DNA hybridization (17.2-23.9%) values among the five novel strains and Maribacter chungangensis CCUG 61948T, Maribacter litoralis SDRB-Phe2T and Maribacter algarum RZ26T were all below the established species delineation thresholds. Based on polyphasic taxonomic analyses, strains 2210JD10-5T, 2304DJ31-5T, 2307UL18-2T, 2307ULW6-5T and 2308TA10-17T represent five novel species of the genus Maribacter, for which the names Maribacter algae sp. nov. (2210JD10-5T=KCTC 102365T=MCCC 1K09794T), Maribacter spongiae sp. nov. (2304DJ31-5T=KCTC 102366T=MCCC 1K09795T), Maribacter corallii sp. nov. (2307UL18-2T=KCTC 102367T=MCCC 1K09802T), Maribacter aquimarinus sp. nov. (2307ULW6-5T=KCTC 102368T=MCCC 1K09801T) and Maribacter taeanensis sp. nov. (2308TA10-17T=KCTC 102369T=MCCC 1K09818T) are proposed.
Keywords: Flavobacteriia; Maribacter algae; Maribacter aquimarinus; Maribacter corallii; Maribacter spongiae; Maribacter taeanensis.