Properties of a mutant recA-encoded protein reveal a possible role for Escherichia coli recF-encoded protein in genetic recombination
A mutation partially suppressing the UV sensitivity caused by recF143 in a uvrA6 background was located at codon 37 of recA where GTG (valine) became ATG (methionine). This mutation, originally named srf-803, was renamed recA803. Little if any suppression of the recF143 defect in UV induction of a lexA regulon promoter was detected. This led to the hypothesis that a defect in recombination repair of UV damage was suppressed by recA803. The mutant RecA protein (RecA803) was purified and compared with wild-type protein (RecA+) as a catalyst of formation of joint molecules. Under suboptimal conditions, RecA803 produces both a higher rate of formation and a higher yield of joint molecules. The suboptimal conditions tested included addition of single-stranded DNA binding protein to single-stranded DNA prior to addition of RecA. We hypothesize that the ability of RecA803 to overcome interference by single-stranded DNA binding protein is the property that allows recA803 to suppress partially the deficiency in repair caused by recF mutations in the uvrA6 background. Implications of this hypothesis for the function of RecF protein in recombination are discussed.
- Research Organization:
- Univ. of California, Berkeley (USA)
- OSTI ID:
- 7092056
- Journal Information:
- Proc. Natl. Acad. Sci. U.S.A.; (United States), Vol. 85:18
- Country of Publication:
- United States
- Language:
- English
Similar Records
Suppression of the UV-sensitive phenotype of Escherichia coli recF mutants by recA(Srf) and recA(Tif) mutations requires recJ+
recA (Srf) suppression of recF deficiency in the postreplication repair of UV-irradiated Escherichia coli K-12
Related Subjects
ESCHERICHIA COLI
GENE RECOMBINATION
PROTEINS
BIOLOGICAL FUNCTIONS
DNA REPAIR
GENETIC MAPPING
MUTATIONS
PLASMIDS
RADIOSENSITIVITY
ULTRAVIOLET RADIATION
BACTERIA
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
CELL CONSTITUENTS
ELECTROMAGNETIC RADIATION
FUNCTIONS
MAPPING
MICROORGANISMS
ORGANIC COMPOUNDS
RADIATIONS
RECOVERY
REPAIR
560130* - Radiation Effects on Microorganisms