Complete Genome Sequence of the Facultative Anaerobic Magnetotactic Bacterium Magnetospirillum sp. strain AMB-1

Magnetospirillum sp. strain AMB-1 is a Gram-negative -proteobacteriumthat synthesizes nano-sized magnetites, referred to as magnetosomes,aligned intracellularly in a chain. The potential of this nano-sizedmaterial is growing and will be applicable to broad researchareas. It has been expected that genome analysis would elucidatethe mechanism of magnetosome formation by magnetic bacteria.Here we describe the genome of Magnetospirillum sp. AMB-1 wildtype, which consists of a single circular chromosome of 4967148bp. For identification of genes required for magnetosome formation,transposon mutagenesis and determination of magnetosome membraneproteins were performed. Analysis of a non-magnetic transposonmutant library focused on three unknown genes from 2752 unknowngenes and three genes from 205 signal transduction genes. Partialproteome analysis of the magnetosome membrane revealed thatthe membrane contains numerous oxidation/reduction proteinsand a signal response regulator that may function in magnetotaxis.Thus, oxidation/reduction proteins and elaborate multidomainsignaling proteins were analyzed. This comprehensive genomeanalysis will enable resolution of the mechanisms of magnetosomeformation and provide a template to determine how magnetic bacteriamaintain a species-specific, nano-sized, magnetic single domainand paramagnetic morphology.