Characterization of the helicase activity of the Escherichia coli UvrAB protein complex

Journal Article · Sun Jan 15 04:00:00 EST 1989 · J. Biol. Chem.; (United States)

OSTI ID:6500298

Oh, E Y; Grossman, L

The requirement for nucleotide hydrolysis in the DNA repair mechanism of the Escherichia coli UvrABC protein complex has been analyzed. The DNA-activated UvrAB ATPase activity is part of a helicase activity exhibited by the UvrAB protein complex. The helicase acts only on short duplexes and, therefore, is unlike other helicases such as those involved in DNA replication that unwind long duplexes. The strand displacement activity occurs in the 5'----3' direction and requires either ATP or dATP. The helicase activity is inhibited by UV photoproducts. The absence of this activity in a complex formed with proteolyzed UvrB (UvrB*), a complex also deficient in the endonuclease activity, suggests that this activity is important in the repair mechanism. The UvrAB protein complex may remain bound to a damaged site and by coupling the energy derived from ATP hydrolysis, alter the DNA conformation around the damage site to one that is permissive for endonucleolytic events. The conformational changes may take the form of DNA unwinding.

• Research Organization: Johns Hopkins Univ. School of Hygiene and Public Health, Baltimore, MD (USA)
• OSTI ID: 6500298
• Journal Information: J. Biol. Chem.; (United States), Journal Name: J. Biol. Chem.; (United States) Vol. 264:2; ISSN JBCHA
• Country of Publication: United States
• Language: English

Related Subjects

550200* -- Biochemistry
59 BASIC BIOLOGICAL SCIENCES
ACID ANHYDRASES
ATP
ATP-ASE
BACTERIA
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
CHEMICAL REACTIONS
DECOMPOSITION
DNA REPAIR
ENZYME ACTIVITY
ENZYMES
ESCHERICHIA COLI
HYDROLASES
HYDROLYSIS
LYSIS
MICROORGANISMS
NUCLEOTIDES
ORGANIC COMPOUNDS
PHOSPHOHYDROLASES
PROTEINS
RECOVERY
REPAIR
SOLVOLYSIS
THERMODYNAMICS