title: Inhibition of protein secretion by cerulenin in Bacillus subtilis.
abstract: Cerulenin at a concentration of 10 micrograms ml-1 only slightly inhibited growth of Bacillus subtilis YY88 while at 50 micrograms ml-1 it inhibited the growth rate by 20-35% in complex media, and by 50-60% in mineral medium containing a single carbon source. Cerulenin (50 micrograms ml-1) only partially prevented the secretion of alpha-amylase, proteases and levansucrase when added to bacteria growing in complex medium, but completely prevented the secretion of these enzymes in the mineral medium. Lower concentrations of cerulenin (10 micrograms ml-1) inhibited the secretion of the enzymes in the mineral medium by up to 40%. When the cells were incubated with L-[35S]-methionine (plus a complete amino acid mixture) in the presence of cerulenin (50 micrograms ml-1), protein secretion was lowered by 68%. Cerulenin inhibited translocation of membrane-bound forms of the secreted enzymes to 18% of the control value and the incorporation of radioactive methionine into membranes to 46%. These results suggest that the membrane-bound forms of secreted proteins play an important role in the secretion process in B. subtilis.
mesh_terms: D000935:Antifungal Agents / Q000494:pharmacology*; D001412:Bacillus subtilis / Q000187:drug effects / Q000201:enzymology* / Q000254:growth & development; D002569:Cerulenin / Q000494:pharmacology*; D006602:Hexosyltransferases / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism*; D008715:Methionine / Q000378:metabolism; D010447:Peptide Hydrolases / Q000378:metabolism; D000516:alpha-Amylases / Q000378:metabolism
chemical_list: D000935:Antifungal Agents; D008565:Membrane Proteins; D002569:Cerulenin; D008715:Methionine; D006602:Hexosyltransferases; C021513:levansucrase; D000516:alpha-Amylases; D010447:Peptide Hydrolases