UmuD mutagenesis protein of Escherichia coli: Overproduction, purification, and cleavage by RecA

Journal Article · Tue Mar 01 04:00:00 EST 1988 · Proceedings of the National Academy of Sciences of the United States of America; (USA)

DOI:https://doi.org/10.1073/pnas.85.6.1811· OSTI ID:6973733

Burckhardt, S E; Woodgate, R; Scheuermann, R H; Echols, H ^[1]

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1. Univ. of California, Berkeley (USA)

The mutation rate of Escherichia coli increases approximately 100-fold after treatment with replication-inhibiting agents such as UV light. This enhanced mutation rate requires the action of the UmuD and UmuC proteins, which are induced as part of the SOS response to DNA damage. To initiate a biochemical characterization of the role of these proteins, the authors have developed a plasmid system that gives efficient expression of the umuD and umuC genes. The umuD and umuC genes were placed under the control of a regulated phage {lambda} P{sub L} promoter and a synthetic ribosome-binding site, and the distance to the UmuD start was adjusted to maximize gene expression. Starting from this overproduction system, they have purified the UmuD protein and studied its interaction with RecA. The SOS response is turned on by the capacity of RecA protein to mediate cleavage of the LexA repressor for SOS-controlled operons. Others have shown that UmuD exhibits sequence homology to LexA around the cleavage site, suggesting a possible cleavage reaction for UmuD. They show that RecA mediates cleavage of UmuD, probably at this site. As with LexA, UmuD also undergoes a self-cleavage reaction. They infer that RecA-mediated cleavage of UmuD is another role for RecA in SOS mutagenesis, probably activating UmuD for its mutagenic function.

• OSTI ID: 6973733
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America; (USA), Journal Name: Proceedings of the National Academy of Sciences of the United States of America; (USA) Journal Issue: 6 Vol. 85:6; ISSN 0027-8424; ISSN PNASA
• Country of Publication: United States
• Language: English

Related Subjects

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59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BACTERIA
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
CELL CONSTITUENTS
DAYS LIVING RADIOISOTOPES
DNA REPAIR
ELECTROMAGNETIC RADIATION
ESCHERICHIA COLI
EVEN-ODD NUCLEI
GENE REGULATION
ISOTOPES
LIGHT NUCLEI
MICROORGANISMS
MOLECULAR BIOLOGY
MUTAGENESIS
NUCLEI
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
PHOSPHORUS 32
PHOSPHORUS ISOTOPES
PLASMIDS
PROTEINS
PURIFICATION
RADIATION EFFECTS
RADIATIONS
RADIOISOTOPES
RECOVERY
REPAIR
SULFUR 35
SULFUR ISOTOPES
ULTRAVIOLET RADIATION