The role of the pro-sequence in the processing and secretion of the thermolysin-like neutral protease from Bacillus cereus.
The Bacillus cereus cnp gene coding for the thermolysin-like neutral protease (TNP) has been cloned, sequenced, and expressed in Bacillus subtilis. The protease is first produced as a pre-pro-protein (M(r) = 61,000); the pro-peptide is approximately two-thirds of the size of the mature protein. The pro-sequence has been compared with those of six other TNPs, and significant homologies have been found. Additionally, the TNP pro-sequences are shown to be homologous to the pro-sequence of Pseudomonas aeruginosa elastase. A mutant has been constructed from cnp, in which 23 amino acids upstream from the pro-protein processing site have been deleted. This region has no homologous analogue in any of the other TNP pro-sequences. The deletion results in a delay of six to eight hours in detection of active protease in the growth medium, as well as a 75% decrease in maximum protease production. N-terminal analysis of the mutant mature protein demonstrates that the processing site is unaltered by the pro-sequence deletion. The deletion must, therefore, modulate the kinetics of processing and/or secretion of the pro-protein.
Wetmore
D R
DR
Department of Biological Sciences, University of Calgary, Alberta, Canada.
Wong
S L
SL
Roche
R S
RS
D000595:Amino Acid Sequence; D001409:Bacillus cereus / Q000201:enzymology / Q000235:genetics*; D001483:Base Sequence; D015153:Blotting, Western; D003001:Cloning, Molecular; D004792:Enzyme Precursors / Q000737:chemistry / Q000378:metabolism*; D008666:Metalloendopeptidases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D011499:Protein Processing, Post-Translational / Q000235:genetics; D012689:Sequence Homology, Nucleic Acid; D013820:Thermolysin / Q000235:genetics*
D004792:Enzyme Precursors; D008666:Metalloendopeptidases; C044194:microbial metalloproteinases; D013820:Thermolysin