The C-terminal half of UvrC protein is sufficient to reconstitute (A)BC excinuclease

Journal Article · Thu Aug 01 04:00:00 EDT 1991 · Proceedings of the National Academy of Sciences of the United States of America; (United States)

DOI:https://doi.org/10.1073/pnas.88.15.6824· OSTI ID:5263094

Lin, J J; Sancar, A ^[1]

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1. University of North Carolina School of Medicine, Chapel Hill (USA)

The UvrC protein is one of three subunits of the Escherichia coli repair enzyme (A)BC excinuclease. This subunit is thought to have at least one of the active sites for nucleophilic attack on the phosphodiester bonds of damaged DNA. To localize the active site, mutant UvrC proteins were constructed by linker-scanning and deletion mutagenesis. In vivo studies revealed that the C-terminal 314 amino acids of the 610-amino acid UvrC protein were sufficient to confer UV resistance to cells lacking the uvrC gene. The portion of the uvrC gene encoding the C-terminal half of the protein was fused to the 3{prime} end of the E. coli malE gene (which encodes maltose binding protein), and the fusion protein MBP-C314C was purified and characterized. The fusion protein, in combination with UvrA and UvrB subunits, reconstituted the excinuclease activity that incised the eighth phosphodiester bond 5{prime} and the fourth phosphodiester bond 3{prime} to a psoralen-thymine adduct. These results suggest that the C-terminal 314 amino acids of UvrC constitute a functional domain capable of interacting with the UvrB-damaged DNA complex and of inducing the two phosphodiester bond incisions characteristic of (A)BC excinuclease.

• OSTI ID: 5263094
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America; (United States), Journal Name: Proceedings of the National Academy of Sciences of the United States of America; (United States) Vol. 88:15; ISSN PNASA; ISSN 0027-8424
• Country of Publication: United States
• Language: English

Related Subjects

560130* -- Radiation Effects on Microorganisms
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AMINO ACID SEQUENCE
BACTERIA
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
CELL CONSTITUENTS
CHEMICAL COMPOSITION
DNA REPAIR
ELECTROMAGNETIC RADIATION
ENZYME ACTIVITY
ENZYMES
ESCHERICHIA COLI
ESTERASES
GENES
HYDROLASES
MICROORGANISMS
MOLECULAR STRUCTURE
MUTAGENESIS
NUCLEASES
ORGANIC COMPOUNDS
PHOSPHODIESTERASES
PLASMIDS
PROTEINS
RADIATIONS
RECOVERY
REPAIR
ULTRAVIOLET RADIATION