Premium
Co‐ordinated functions of Mms proteins define the surface structure of cubo‐octahedral magnetite crystals in magnetotactic bacteria
Author(s) -
Arakaki Atsushi,
Yamagishi Ayana,
Fukuyo Ayumi,
Tanaka Masayoshi,
Matsunaga Tadashi
Publication year - 2014
Publication title -
molecular microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.857
H-Index - 247
eISSN - 1365-2958
pISSN - 0950-382X
DOI - 10.1111/mmi.12683
Subject(s) - magnetotactic bacteria , magnetite , magnetosome , biology , biomineralization , mutant , bacteria , biophysics , crystallography , microbiology and biotechnology , gene , biochemistry , chemistry , genetics , astrobiology , paleontology
Summary Magnetotactic bacteria synthesize magnetosomes comprised of membrane‐enveloped single crystalline magnetite ( Fe 3 O 4 ). The size and morphology of the nano‐sized magnetite crystals (< 100 nm) are highly regulated and bacterial species dependent. However, the control mechanisms of magnetite crystal morphology remain largely unknown. The group of proteins, called Mms ( Mms5 , Mms6 , Mms7 , and Mms13 ), was previously isolated from the surface of cubo‐octahedral magnetite crystals in M agnetospirillum magneticum strain AMB ‐1. Analysis of an mms6 gene deletion mutant suggested that the Mms6 protein plays a major role in the regulation of magnetite crystal size and morphology. In this study, we constructed various mms gene deletion mutants and characterized the magnetite crystals formed by the mutant strains. Comparative analysis showed that all mms genes were involved in the promotion of crystal growth in different manners. The phenotypic characterization of magnetites also suggested that these proteins are involved in controlling the geometries of the crystal surface structures. Thus, the co‐ordinated functions of Mms proteins regulate the morphology of the cubo‐octahedral magnetite crystals in magnetotactic bacteria.