Shewanella mesophila sp. nov., Isolated from Marine Sponge in tropical area, Chuuk Island, Micronesia

Abstract

A mesotrophic bacterium, strain MEBiC 05444T, was isolated from a marine sponge collected in tropical area, Chuuk Island, Micronesia. Cells are Gram negative, non-spore forming, non-motile and rod-shaped (1.4-2.1㎛ ´ 0.4-0.7㎛). Growth is observed between 16 and 37℃ (optimum 33℃), at pH 5.0-8.5 (optimum 6.0) and in the presence of 1.5-6.0% (optimum 2.0%) NaCl. The 16S rRNA gene sequence of strain MEBiC 05444T showed high similarity (92.2-96.8%) with members of the genus Shewanella, especially with S.irciniae UST040317-058T (96.8%), S. spongiae HJ039T (95.1%), S. marina C4T (94.7%), and S. algae ATCC 51192T (94.2%). The isolate required Mg2+ and Ca2+ ions in addition to K+ ion for growth. The dominant fatty acids were C12:0, iso-C13:0 3-OH and C16 : 17c. The major respiratory quinone is Q-8. The DNA G+C content is 42.2 mol%. From this polyphasic taxonomical evidence, strain MEBiC 05444T should be identified as a novel species in the genus Shewanella and proposed it as the name Shewanella mesophila sp. nov. The type strain is MEBiC 05444T.