Key gene networks that control magnetosome biomineralization in magnetotactic bacteria

Abstract

Magnetotactic bacteria (MTB) are a group of phylogenetically and morphologically diverse prokaryotes that have the capability of sensing Earth's magnetic field via nanocrystals of magnetic iron minerals. These crystals are enclosed within intracellular membranes or organelles known as magnetosomes and enable a sensing function known as magnetotaxis. Although MTB were discovered over half a century ago, the study of the magnetosome biogenesis and organization remains limited to a few cultured MTB strains. Here, we present an integrative genomic and phenomic analysis to investigate the genetic basis of magnetosome biomineralization in both cultured and uncultured strains from phylogenetically diverse MTB groups. The magnetosome gene contents/networks of strains are corelated to magnetic particle morphology and chain configuration. We propose a general model for gene networks that control/regulate magnetosome biogenesis and chain assembly in MTB systems.

Micromagnetic calculation of the magnetite magnetosomal morphology control of magnetism in magnetotactic bacteria

“…Previous studies indicate a correlation between the crystal habits of biogenic magnetite or greigite and MTB species owing to a strong genetically controlled biomineralization [2,11,30,47,48]. For example, Desulfobacterota phylum and Nitrospirota phylum synthesize straight bullet-shaped and curved bullet-shaped magnetite, respectively [48]. Moreover, MTB have been widely found in various modern aquatic and sedimentary environments [47,49].…”

“…Previous studies indicate a correlation between the crystal habits of biogenic magnetite or greigite and MTB species owing to a strong genetically controlled biomineralization royalsocietypublishing.org/journal/rsif J. R. Soc. Interface 20: 20230297 [2,11,30,47,48]. For example, Desulfobacterota phylum and Nitrospirota phylum synthesize straight bullet-shaped and curved bullet-shaped magnetite, respectively [48].…”

“…Interface 20: 20230297 [2,11,30,47,48]. For example, Desulfobacterota phylum and Nitrospirota phylum synthesize straight bullet-shaped and curved bullet-shaped magnetite, respectively [48]. Moreover, MTB have been widely found in various modern aquatic and sedimentary environments [47,49].…”

Glacial‐Interglacial Circulation and Climatic Changes in the South Indian Ocean (Kerguelen Plateau Region) Recorded by Detrital and Biogenic Magnetic Minerals

“…Magnetofossils are well‐known biogenic magnetic minerals preserved in sediments or sedimentary rocks (Kirschvink & Chang, 1984; Kopp & Kirschvink, 2008; Pan et al., 2005; Roberts et al., 2012). They are actually fossil remains of magnetotactic bacteria (MTB), and promising recorders of paleoenvironmental information because of their ideal single domain (SD) nature and distinctive morphologies associated with different taxonomic MTB groups with contrasting habitat preferences (Li et al., 2013, 2021; Li, Liu, Wang, et al., 2020; P. Y. Liu et al., 2022; Pósfai et al., 2013). For instance, magnetofossil abundance and hematite flux changes have been used to indicate iron fertilization occurrence in open ocean settings (Roberts et al., 2011; Yamazaki & Ikehara, 2012).…”

Linking minerals to bacterial genes

“…In recent work by Liu et al . [ 10 ], they further integrated metagenomics to create a more robust methodology for the genomic and phenomic study of uncultured and cultured MTB. They generated new data sets of genomic and magnetosome morphological information for 15 uncultured MTB strains.…”