title: Implication of proteases in the respiration dependent inactivation of the lactose permease of E. coli.
abstract: The lactose permease of E. coli becomes irreversibly inactivated during lactose transport under conditions of high respiratory activity. This inactivation is characterized by a decrease in the steady state of lactose accumulation, a decrease in the influx rate of lactose, and a decrease in the transmembrane electrical potential. We report here that inhibitors of serine proteases (phenylmethylsulfonyl fluoride and N-alpha-P-tosyl-L-lysine chloromethyl ketone) prevent this inactivation, thus implicating proteases in this process.
mesh_terms: D004926:Escherichia coli / Q000201:enzymology*; D029968:Escherichia coli Proteins; D007785:Lactose / Q000378:metabolism; D008564:Membrane Potentials; D049990:Membrane Transport Modulators; D026901:Membrane Transport Proteins / Q000037:antagonists & inhibitors*; D009004:Monosaccharide Transport Proteins; D010101:Oxygen Consumption; D010447:Peptide Hydrolases / Q000378:metabolism*; D010664:Phenylmethylsulfonyl Fluoride / Q000494:pharmacology; D011480:Protease Inhibitors; D012697:Serine Endopeptidases; D027981:Symporters; D013997:Time Factors; D014107:Tosyllysine Chloromethyl Ketone / Q000494:pharmacology
chemical_list: D029968:Escherichia coli Proteins; C050221:LacY protein, E coli; D049990:Membrane Transport Modulators; D026901:Membrane Transport Proteins; D009004:Monosaccharide Transport Proteins; D011480:Protease Inhibitors; D027981:Symporters; D014107:Tosyllysine Chloromethyl Ketone; D010664:Phenylmethylsulfonyl Fluoride; C021499:lactose permease; D010447:Peptide Hydrolases; D012697:Serine Endopeptidases; D007785:Lactose