Strain SYSU M10002T was isolated from a water sample collected from the coastal region of Pearl River estuary, Guangdong Province, southern China. The taxonomic position of the isolate was investigated by polyphasic taxonomic approaches. The isolate was found to be Gram-negative, non-motile, short rods and aerobic. The strain was able to grow at 14-37 °C, pH 6.0-10.0 and in the presence of up to 0.5% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain SYSU M10002T is a member of the family Sphingomonadaceae, with high sequence similarity to Sphingorhabdus buctiana T5T (95.1%). Overall genomic related indices between the genome of strain SYSU M10002T and those of related strains were low to moderate (AAI values < 64.3%; POCP values < 58%), indicating that strain SYSU M10002T represents a novel lineage within the family Sphinogomonadaceae. Strain SYSU M10002T contained homospermidine as its polyamine. The major polar lipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, sphingoglycolipid, two unidentified phospholipids and an unidentified aminolipid. Ubiquinone Q-9 (44.9%) and Q-10 (43.2%) were the dominant respiratory quinones, along with a minor amount of Q-8 (11.9%). The predominant cellular fatty acids (> 10%) identified were summed feature 3 (C16:1ω7c and/or C16:1ω6c), summed feature 8 (C18:1ω7c) and C14:0 2-OH. The genomic DNA G+C content was 64.0%. Based on the analyses of the phenotypic, genotypic and phylogenetic characteristics, strain SYSU M10002T is determined to represent a novel species of a novel genus, for which the name Aestuariisphingobium litorale gen. nov., sp. nov. is proposed. The type strain of the species is SYSU M10002T (= KCTC 52944T = NBRC 112961T).
Keywords: Aestuariisphingobium litorale gen. nov., sp. nov.; Pearl River estuary; Polyphasic taxonomy.