Genomic analysis of a pure culture of magnetotactic bacterium Terasakiella sp. SH-1

Abstract

Magnetotactic bacteria(MTB) display magnetotaxis ability because of biomineralization of intracellular nanometer-sized, membrane-bound organelles termed magnetosomes. Despite having been discovered more than half a century, only a few representatives of MTB have been isolated and cultured in the laboratory. In this study, we report the genomic characterization of a novel marine magnetotactic spirillum strain SH-1 belonging to the genus Terasakiella that was recently isolated. A gene encoding haloalkane dehalogenase, which is involved in the degradation of chlorocyclohexane, chlorobenzene, chloroalkane, and chloroalkene, was identified. SH-1 genome contained cysCHI and soxBAZYX genes, thus potentially capable of assimilatory sulfate reduction to H 2 S and using thiosulfate as electron donors and oxidizing it to sulfate. Genome of SH-1 also contained genes encoding periplasmic dissimilatory nitrate reductases(napAB), assimilatory nitrate reductase(nasA) and assimilatory nitrite reductases(nasB), suggesting that it is capable of gaining energy by converting nitrate to ammonia. The pure culture of Terasakiella sp. SH-1 together with its genomic results offers new opportunities to examine biology, physiology, and biomineralization mechanisms of MTB.