Rheinheimera salexigens sp nov., isolated from a fishing hook, and emended description of the genus Rheinheimera

A Gram-negative, rod-shaped bacterium, designated KH87(T), was isolated from a fishing hook that had been baited and suspended in seawater off O'ahu, Hawai'i. Based on a comparison of 1524 nt of the 16S rRNA gene sequence of strain KH87(T), its nearest neighbours were the Gammaproteobacteria Rheinheimera nanhaiensis E407-8(T) (96.2% identity), Rheinheimera chironomi K19414(T) (96.0 %), Rheinheimera pacifica KMM 1406(T) (95.8 %), Rheinheimera muenzenbergensis E49(T) (95.7 %), Alishewanella solinquinati KMK6(T) (94.9 %) and Arsukibacterium ikkense GCM72(T) (94.6 %). Cells of KH87(T) were motile by a single polar flagellum, strictly aerobic, and catalase-and oxidase-positive. Growth occurred between 4 and 39 degrees C, and in a circumneutral pH range. Major fatty acids in whole cells of strain KH87(T) were cis-9-hexadecenoic acid, hexadecanoic acid and cis-11-octadecenoic acid. The quinone system contained mostly menaquinone MK-7, and a minor amount of ubiquinone Q-8. The polar lipid profile contained the major lipids phosphatidylglycerol, phosphatidylserine, phosphatidylethanolamine, an unidentified aminolipid, and a lipid not containing phosphate, an amino group or a sugar moiety. Putrescine was the major polyamine. Physiological, biochemical and genomic data, including obligate halophily, absence of amylolytic activity, a quinone system dominated by MK-7 and DNA G+C content (42.0 mol%) distinguished KH87(T) from extant Rheinheimera species; strain KH87(T) was also distinguished by a multi-locus sequence analysis of aligned and concatenated 16S rRNA, gyrB, rpoB and rpoD gene sequences. Based on phenotypic and genotypic differences, the species Rheinheimera salexigens sp. nov. is proposed to accommodate KH87(T) as the type strain (=ATCC BAA-2715(T)=CIP 111115(T)). An emended description of the genus Rheinheimera is also proposed.