title: Inactivation of the flagellin gene flaA in Magnetospirillum gryphiswaldense results in nonmagnetotactic mutants lacking flagellar filaments.
abstract: Magnetotactic bacteria synthesize magnetosomes, which cause them to orient and migrate along magnetic field lines. The analysis of magnetotaxis and magnetosome biomineralization at the molecular level has been hindered by the unavailability of genetic methods, namely the lack of a means to introduce directed gene-specific mutations. Here we report a method for knockout mutagenesis by homologous recombination in Magnetospirillum gryphiswaldense. Multiple flagellin genes, which are unlinked in the genome, were identified in M. gryphiswaldense. The targeted disruption of the flagellin gene flaA was shown to eliminate flagella formation, motility, and magnetotaxis. The techniques described in this paper will make it possible to take full advantage of the forthcoming genome sequences of M. gryphiswaldense and other magnetotactic bacteria.
authors.affiliation: Max Planck Institute for Marine Microbiology, 28359 Bremen, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Schultheiss
authors.forename: Michael
authors.initials: M
authors.lastname: Kube
authors.forename: Dirk
authors.initials: D
authors.lastname: Schüler
mesh_terms: D003227:Conjugation, Genetic; D005407:Flagella / Q000378:metabolism*; D005408:Flagellin / Q000235:genetics* / Q000378:metabolism; D017353:Gene Deletion; D008280:Magnetics; D042201:Magnetospirillum / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D008969:Molecular Sequence Data; D009068:Movement; D010957:Plasmids; D011995:Recombination, Genetic
chemical_list: D005408:Flagellin; C067138:flaA protein, bacteria