Palleronia sediminis sp. nov. and Flavivirga algicola sp. nov., two marine bacteria isolated from offshore areas near Weihai

Flavivirga spongiicola sp. nov. and Flavivirga abyssicola sp. nov., Isolated from Marine Environments

Two novel Gram-stain-negative, strictly-aerobic, rod-shaped (1.2 ± 3.4 μm × 0.3 ± 0.7 μm), and non-motile marine bacterial species, designated MEBiC05379T and MEBiC07777T, were isolated from a marine sponge Pseudaxinella sp. in Gangneung City and deep-sea sediments of the Ulleung basin in the East Sea of Korea, respectively. The 16S rRNA gene sequence analysis revealed high levels of similarities between these strains and members of the genus Flavivirga (97.0-98.4% sequence identities). Both novel strains revealed as mesophilic, neutrophilic in pH and slightly halophilic. Similar to those of other Flavivirga members, the primary cellular fatty acids of both strains were iso-C15:0, iso-C15:1 G, iso-C15:03-OH, and iso-C17:0 3-OH, with MEBiC05379T and MEBiC07777T containing relatively higher proportions of C12:0 and summed feature 3 (C16:1ω7c and/or C16:1ω6c). In both taxa, the major isoprenoid quinone was MK-6. The DNA G + C contents of MEBiC05379T and MEBiC07777T genomes were 32.62 and 32.46 mol%, respectively. Compared to other members of Flavivirga, both strains exhibited similar DNA G + C ratio and fatty acids pattern, yet enzyme expression and carbon sources utilization pattern were different. Genomes of the genus Flavivirga showed enzyme preferences to fucoidan and sulfated galactans. Considering the monophyly rule, AAI values delineate the genus Flavivirga from adjacent genera calculated to be 76.0-78.7%. Based on the phenotypic, genomic and biochemical data, strains for MEBiC05379T and MEBiC07777T thus represent two novel species in the genus Flavivirga, for which the names Flavivirga spongiicola sp. nov. (MEBiC05379T [= KCTC 92527 T = JCM 16662 T]), and Flavivirga abyssicola sp. nov. (MEBiC07777T [= KCTC 92563 T = JCM 36477 T]) are proposed.

Phycicoccus avicenniae sp. nov., a novel endophytic actinomycete isolated from a branch of Avicennia mariana

A novel endophytic actinomycete, designated strain BSK3Z-2 ^T, was isolated from a surface-sterilised branch of Avicennia mariana from Shankou Mangrove Nature Reserve, Guangxi Zhuang Autonomous Region, China. Cells were observed to be Gram-stain positive, aerobic, asporogenous and rod-shaped. Strain BSK3Z-2 ^T was found to grow optimally at 30 °C, pH 7.0 and in the presence of 1% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain BSK3Z-2 ^T belongs to the genus Phycicoccus and has high 16S rRNA gene sequence similarity of 98.1% with Phycicoccus endophyticus IP6SC6^T. Phylogenetic analysis based on the genome of strain BSK3Z-2 ^T was performed by extracting and aligning 39 conserved proteins and 88 housekeeping genes, which further confirmed the phylogenetic assignment of strain BSK3Z-2 ^T. The draft genome of strain BSK3Z-2 ^T is 3.54 Mbp with a DNA G + C content of 73.8%. The average nucleotide identity (ANI), amino acid identity (AAI) and digital DNA-DNA hybridization (dDDH) values between strain BSK3Z-2 ^T and species of genus Phycicoccus were 73.8-85.6%, 64.5-75.9% and 19.5-23.8%, respectively, which are below the standard cut-off values for bacterial species delineation. Strain BSK3Z-2 ^T contains MK-8(H₄) as the dominant menaquinone. The cell wall peptidoglycan contains meso-diaminopimelic acid. The polar lipids profile of strain BSK3Z-2 ^T was found to contain diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol. The predominant fatty acids were identified as C_15:0, C_17:0, iso-C_16:0 and C_17:1ω8c. Comparing the phenotypic and phylogenetic features of the strain BSK3Z-2 ^T and related taxa, strain BSK3Z-2 ^T is concluded to represent a novel species of the genus Phycicoccus, for which the name Phycicoccus avicenniae sp. nov. is proposed. The type strain is BSK3Z-2 ^T (= CGMCC 1.18743 ^T = JCM 34335 ^T).