sp. nov. and sp. nov., isolated from marine algae.

Two Gram-stain-negative, facultatively aerobic, and motile rod bacteria, designated as strains KJ51-3 and 15G1-11, were isolated from marine algae collected in the Republic of Korea. Both strains exhibited catalase- and oxidase-positive activities. Optimum growth conditions for strain KJ51-3 were observed at 30 °C and pH 6.0-8.0, with 1.0-7.0 % (w/v) NaCl, whereas strain 15G1-11 exhibited optimal growth at 30 °C, pH 7.0, and 1.0-5.0 % NaCl. Major fatty acids detected in both strains included C, C 3-OH and summed features 3 (C 7 and/or C 6) and 8 (C 7 and/or C 6). As for polar lipids, strain KJ51-3 contained phosphatidylethanolamine (PE), phosphatidylglycerol (PG), diphosphatidylglycerol, and two unidentified phospholipids, whereas strain 15G1-11 had PE, PG, and an unidentified aminolipid. Ubiquinone-8 was the predominant respiratory quinone in both strains, with minor detection of ubiquinone-9 in strain KJ51-3. The genomic DNA G+C contents were 44.0 mol% for strain KJ51-3 and 40.5 mol% for strain 15G1-11. Phylogenetic analyses based on both 16S rRNA gene and genome sequences placed strains KJ51-3 and 15G1-11 into distinct lineages within the genus , most closely related to 328 (98.6 %) and SM1966 (98.3 %), respectively. Strains KJ51-3 and 15G1-11 exhibited a 94.6 % 16S rRNA gene sequence similarity and a 70.7 % average nucleotide identity (ANI), with ANI values of 91.9 and 79.3 % between them and 328 and SM1966, respectively, indicating that they represent novel species. In summary, based on their phenotypic, chemotaxonomic, and phylogenetic properties, strains KJ51-3 and 15G1-11 are proposed to represent novel species within the genus , for which the names sp. nov. (KJ51-3=KACC 22756=JCM 35591) and sp. nov. (15G1-11=KACC 22593=JCM 35412) are respectively proposed.