Shewanella fodinae sp. nov., isolated from a coal mine and from a marine lagoon

Abstract

Strains JC15T and JC19 were isolated from samples collected from different locations in India, including a coal mine and a marine lagoon. Both strains were Gram-stain-negative rods, motile by means of a single polar flagellum, catalase- and oxidase-positive, and hydrolysed casein, produced H2S and showed β-haemolysis. Strain JC15T grew optimally at pH 6 (range pH 5-8) while strain JC19 grew optimally at pH 7 (range pH 6-9) and both had a growth temperature optimum of 30-37 °C (range 22-40 °C). Both strains could grow chemoorganoheterotrophically and chemolithoautotrophically. Neither strain required NaCl for growth and both could tolerate up to 9% (w/v) NaCl, with optimum growth at 5% NaCl. Vitamin B12 was required as a growth factor by both strains. The major fatty acids were iso-C15 : 0, C17 : 1ω8c and iso-C 13 : 0 3-OH. The DNA G+C contents of strains JC15T and JC19 were 53.6 and 54.3 mol%, respectively. A phylogenetic tree based on 16S rRNA gene sequence analysis showed that strains JC15T and JC19 were most closely related to Shewanella haliotis DW01T (approximately 94% sequence similarity) and to other members of the genus Shewanella. Genomic relatedness (DNA - DNA hybridization) between strains JC15T and JC19 is 88 %. On the basis of phenotypic and molecular genetic evidence, strain JC15T represents a novel species of the genus Shewanella, for which the name Shewanella fodinae sp. nov. is proposed. The type strain is JC15 T (=CCUG 57102T =NBRC 105216T =KCTC 22506 T). © 2010 IUMS.