title: A single mutation in the M-subunit of Rhodospirillum rubrum confers herbicide resistance.
abstract: Cells of the photosynthetic bacterium Rhodospirillum rubrum were rendered resistant against the inhibitor 2-(1-phenyl)ethylamino-3-propionylamino-4-cyano-thiazole (PPCTH). Electron transport in reaction centers prepared from one of the mutants (M6) was neither inhibited by PPCTH and other NH-thiazoles nor terbutryn. These inhibitors are known to bind at the Q(B) site of the L-subunit. Compared to the wild type, chromatophores from M6 exhibited strongly altered Q(B)- Fe2+ and Q(A)- Fe2+ EPR signals. Inhibitor resistance is due to a mutation in the bacterial reaction center M-subunit, where Glu234 is exchanged against Lys. This is the first example of an inhibitor resistance in the Q(B) site caused by a mutation in the M-subunit.
authors.affiliation: Lehrstuhl Biochemie der Pflanzen, Ruhr-Universität, Bochum, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Sopp
authors.forename: W A
authors.initials: WA
authors.lastname: Rutherford
authors.forename: W
authors.initials: W
authors.lastname: Oettmeier
mesh_terms: D004352:Drug Resistance, Microbial; D004578:Electron Spin Resonance Spectroscopy; D018698:Glutamic Acid / Q000235:genetics; D006540:Herbicides / Q000494:pharmacology*; D008239:Lysine / Q000235:genetics; D009154:Mutation; D045322:Photosynthetic Reaction Center Complex Proteins / Q000187:drug effects* / Q000235:genetics*; D012247:Rhodospirillum rubrum / Q000187:drug effects* / Q000235:genetics* / Q000254:growth & development; D013844:Thiazoles / Q000494:pharmacology*
chemical_list: C106981:2-(1-phenyl)ethylamino-3-propionylamino-4-cyanothiazole; D006540:Herbicides; D045322:Photosynthetic Reaction Center Complex Proteins; D013844:Thiazoles; D018698:Glutamic Acid; D008239:Lysine