Comparative genomic analysis of magnetotactic bacteria from the Deltaproteobacteria provides new insights into magnetite and greigite magnetosome genes required for magnetotaxis. (23rd April 2013)

• Record Type: Journal Article
• Authors: Lefèvre, Christopher T.; Trubitsyn, Denis; Abreu, Fernanda; Kolinko, Sebastian; Jogler, Christian; de, Luiz Gonzaga Paula; de, Ana Tereza R.; Kube, Michael; Reinhardt, Richard; Lins, Ulysses; Pignol, David; Schüler, Dirk; Bazylinski, Dennis A.; Ginet, Nicolas
• Is Part Of: Environmental microbiology. Volume 15:Number 10(2013:Oct.)
• Page Start: 2712
• Page End: 2735
• Publication Date: 2013-04-23
• Subjects: Microbial ecology -- Periodicals; Environmental Microbiology -- Periodicals; 579.17
• DOI: 10.1111/1462-2920.12128
• Languages: English
• ISSNs: 1462-2912

Abstract

<abstract abstract-type="main"> <title>Summary</title> <p>Magnetotactic bacteria (MTB) represent a group of diverse motile prokaryotes that biomineralize magnetosomes, the organelles responsible for magnetotaxis. Magnetosomes consist of intracellular, membrane‐bounded, tens‐of‐nanometre‐sized crystals of the magnetic minerals magnetite (Fe<sub>3</sub>O<sub>4</sub>) or greigite (Fe<sub>3</sub>S<sub>4</sub>) and are usually organized as a chain within the cell acting like a compass needle. Most information regarding the biomineralization processes involved in magnetosome formation comes from studies involving <italic>Alphaproteobacteria</italic> species which biomineralize cuboctahedral and elongated prismatic crystals of magnetite. Many magnetosome genes, the <italic>mam</italic> genes, identified in these organisms are conserved in all known MTB. Here we present a comparative genomic analysis of magnetotactic <italic>Deltaproteobacteria</italic> that synthesize bullet‐shaped crystals of magnetite and/or greigite. We show that in addition to <italic>mam</italic> genes, there is a conserved set of genes, designated <italic>mad</italic> genes, specific to the magnetotactic <italic>Deltaproteobacteria</italic>, some also being present in <italic>Candidatus</italic> Magnetobacterium bavaricum of the <italic>Nitrospirae</italic> phylum, but absent in the magnetotactic <italic>Alphaproteobacteria</italic>. Our results suggest that the number of genes associated with magnetotaxis in magnetotactic <italic>Deltaproteobacteria</italic> is larger than previously thought. We also demonstrate that the minimum set of <italic>mam</italic> genes necessary for magnetosome formation in <italic>Magnetospirillum</italic> is also conserved in magnetite‐producing, magnetotactic <italic>Deltaproteobacteria</italic>. Some putative novel functions of <italic>mad</italic> genes are discussed.</p> </abstract>