Alteromonas portus sp. nov., an alginate lyase-excreting marine bacterium

An alginate lyase-excreting bacterium, designated strain HB161718^T, was isolated from coastal sand collected from Tanmen Port in Hainan, PR China. Cells were Gram-stain-negative rods and motile with a single polar flagellum. Its major isoprenoid quinone was ubiquinone 8 (Q-8), and its cellular fatty acid profile mainly consisted of C_16 : 1 ω7c and/or C_16 : 1 ω6c, C_18 : 1 ω6c and/or C_18 : 1 ω7c, C_16 : 0, C_17 : 0 10-methyl and C_16 : 0 N alcohol. The G+C content of the genomic DNA was 44.1 mol%. 16S rRNA gene sequence analysis suggested that strain HB161718^T belonged to the genus Alteromonas, sharing 99.5, 99.4, 99.2, 98.9 and 98.5 % sequence similarities to its closest relatives, Alteromonas macleodii JCM 20772^T, Alteromonas gracilis 9a2^T, Alteromonas australica H17^T, Alteromonas marina SW-47^T and Alteromonas mediterranea DE^T, respectively. The low values of DNA-DNA hybridization and average nucleotide identity showed that it formed a distinct genomic species. The combined phenotypic and molecular features supported the conclusion that strain HB161718^T represents a novel species of the genus Alteromonas, for which the name Alteromonas portus sp. nov. is proposed. The type strain is HB161718^T (=CGMCC 1.13585^T=JCM 32687^T).