title: SecY protein, a membrane-embedded secretion factor of E. coli, is cleaved by the ompT protease in vitro.
abstract: SecY is an integral membrane protein, spanning the cytoplasmic membrane of E. coli probably 10 times and required for efficient translocation of other proteins across the membrane. We report here that this protein can be specifically cleaved at the central region of the polypeptide after cell disruption, and cytoplasmic membrane preparations often contain a degradation product of SecY. This cleavage was ascribed to the action of the outer membrane-associated protease specified by the ompT gene, since the cleavage was not observed in ompT-defective mutants. Thus, we propose that an ompT mutant should be used for in vitro analysis of protein translocation and the SecY protein. We mutated the ompT gene by insertion of a kanamycin resistance determinant to facilitate strain construction by P1 transduction.
authors.affiliation: Institute for Virus Research, Kyoto University, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Akiyama
authors.forename: K
authors.initials: K
authors.lastname: Ito
mesh_terms: D001426:Bacterial Proteins / Q000302:isolation & purification / Q000378:metabolism*; D002462:Cell Membrane / Q000032:analysis / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins; D005798:Genes, Bacterial; D015151:Immunoblotting; D008565:Membrane Proteins / Q000378:metabolism*; D009154:Mutation; D000069816:SEC Translocation Channels; D012697:Serine Endopeptidases / Q000235:genetics / Q000378:metabolism*; D013379:Substrate Specificity
chemical_list: D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D008565:Membrane Proteins; D000069816:SEC Translocation Channels; C057841:SecY protein, E coli; D012697:Serine Endopeptidases; C057840:omptin outer membrane protease