Photobacterium gaetbulicola sp. nov., a lipolytic bacterium isolated from a tidal flat sediment

Abstract

A Gram-negative, motile, non-spore-forming and lipolytic bacterial strain, designated Gung47(T), was isolated from a tidal flat on the west coast of Korea. Strain Gung47(T) grew optimally at 30 °C and with 2-5 % (w/v) NaCl. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain Gung47(T) belonged to the genus Photobacterium. Strain Gung47(T) exhibited 98.1 % 16S rRNA gene sequence similarity with Photobacterium rosenbergii LMG 22223(T) and 94.3-96.3 % similarity with other type strains of species of the genus Photobacterium. Strain Gung47(T) exhibited 47 % DNA-DNA relatedness to P. rosenbergii LMG 22223(T). Strain Gung47(T) contained Q-8 as the predominant ubiquinone and C(16 : 1)ω7c and/or iso-C(15 : 0) 2-OH, C(16 : 0) and C(18 : 1)ω7c as the major fatty acids. In this study, two closely related type strains, P. rosenbergii LMG 22223(T) and Photobacterium halotolerans LMG 22194(T), were also found to have Q-8 as the predominant ubiquinone. The DNA G+C content of strain Gung47(T) was 50.6 mol%. The differential phenotypic properties together with the phylogenetic and genetic distinctiveness of strain Gung47(T) demonstrated that this strain is distinguishable from recognized Photobacterium species. Therefore, strain Gung47(T) is considered to represent a novel species of the genus Photobacterium, for which the name Photobacterium gaetbulicola sp. nov. is proposed. The type strain is Gung47(T) (=KCTC 22804(T) =CCUG 58399(T)).