Format

Send to

Choose Destination
Cell. 1993 Jun 18;73(6):1165-73.

LexA and lambda Cl repressors as enzymes: specific cleavage in an intermolecular reaction.

Author information

1
Department of Biochemistry, University of Arizona, Tucson 85721.

Abstract

During the SOS response, LexA repressor is inactivated by specific cleavage. Although cleavage requires RecA protein in vivo, RecA acts indirectly as a coprotease by stimulating an inherent self-cleavage activity of LexA. In lambda lysogens, cleavage of lambda Cl repressor in a similar but far slower reaction results in prophage induction. We describe an intermolecular cleavage reaction in which the C-terminal fragment of LexA acted as an enzyme to cleave other molecules of LexA. The C-terminal fragment of lambda repressor cleaved the LexA substrates about as efficiently as did the LexA enzyme, suggesting that the slow rate of Cl self-cleavage results from a weak interaction between its cleavage site and the active site.

PMID:
8513500
DOI:
10.1016/0092-8674(93)90645-7
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center