Nucleic Acids Research, 2001, Vol. 29, No. 2 553-564
© 2001 Oxford University Press
Efficient recognition of substrates and substrate analogs by the adenine glycosylase MutY requires the C-terminal domain
Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, UT 84112-0850, USA
The Escherichia coli DNA repair enzyme MutY plays an important role in the prevention of DNA mutations by removing misincorporated adenine residues from 7,8-dihydro-8-oxo-2'-deoxyguanosine:2'-deoxyadenosine (OG:A) mispairs. The N-terminal domain of MutY (Stop 225, Met1–Lys225) has a sequence and structure that is characteristic of a superfamily of base excision repair glycosylases; however, MutY and its homologs contain a unique C-terminal domain. Previous studies have shown that the C-terminal domain confers specificity for OG:A substrates over G:A substrates and exhibits homology to the d(OG)TPase MutT, suggesting a role in OG recognition. In order to provide additional information on the importance of the C-terminal domain in damage recognition, we have investigated the kinetic properties of a form lacking this domain (Stop 225) under multiple- and single-turnover conditions. In addition, the interaction of Stop 225 with a series of non-cleavable substrate and product analogs was evaluated using gel retardation assays and footprinting experiments. Under multiple-turnover conditions Stop 225 exhibits biphasic kinetic behavior with both OG:A and G:A substrates, likely due to rate-limiting DNA product release. However, the rate of turnover of Stop 225 was increased 2-fold with OG:A substrates compared to the wild-type enzyme. In contrast, the intrinsic rate for adenine removal by Stop 225 from both G:A and OG:A substrates is significantly reduced (10- to 25-fold) compared to the wild-type. The affinity of Stop 225 for substrate analogs was dramatically reduced, as was the ability to discriminate between substrate analogs paired with OG over G. Interestingly, similar hydroxyl radical and DMS footprinting patterns are observed for Stop 225 and wild-type MutY bound to DNA duplexes containing OG opposite an abasic site mimic or a non-hydrogen bonding A analog, suggesting that similar regions of the DNA are contacted by both enzyme forms. Importantly, Stop 225 has a reduced ability to prevent DNA mutations in vivo. This implies that the reduced adenine glycosylase activity translates to a reduced capacity of Stop 225 to prevent DNA mutations in vivo.
* To whom correspondence should be addressed. Tel: +1 801 585 9718; Fax: +1 801 587 9657; Email: david{at}chemistry.chem.utah.edu Present address: Marie-Pierre Golinelli, HIV Drug Resistance Program, National Cancer Institute–FCRDC, PO Box B, Building 539, Frederick, MD 21702-1201, USA
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  H. Bai and A-L. Lu Physical and Functional Interactions between Escherichia coli MutY Glycosylase and Mismatch Repair Protein MutS J. Bacteriol., February 1, 2007; 189(3): 902 - 910. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. Yavin, E. D. A. Stemp, V. L. O'Shea, S. S. David, and J. K. Barton Electron trap for DNA-bound repair enzymes: A strategy for DNA-mediated signaling PNAS, March 7, 2006; 103(10): 3610 - 3614. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. Yavin, A. K. Boal, E. D. A. Stemp, E. M. Boon, A. L. Livingston, V. L. O'Shea, S. S. David, and J. K. Barton From The Cover, Long-Range Electron Transfer Special Feature: Protein-DNA charge transport: Redox activation of a DNA repair protein by guanine radical PNAS, March 8, 2005; 102(10): 3546 - 3551. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. C. Manuel, K. Hitomi, A. S. Arvai, P. G. House, A. J. Kurtz, M. L. Dodson, A. K. McCullough, J. A. Tainer, and R. S. Lloyd Reaction Intermediates in the Catalytic Mechanism of Escherichia coli MutY DNA Glycosylase J. Biol. Chem., November 5, 2004; 279(45): 46930 - 46939. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. M. Boon, A. L. Livingston, N. H. Chmiel, S. S. David, and J. K. Barton DNA-mediated charge transport for DNA repair PNAS, October 28, 2003; 100(22): 12543 - 12547. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. P. Cheadle and J. R. Sampson Exposing the MYtH about base excision repair and human inherited disease Hum. Mol. Genet., October 15, 2003; 12(90002): R159 - 165. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. A. B. McCann and P. J. Berti Adenine Release Is Fast in MutY-catalyzed Hydrolysis of G:A and 8-Oxo-G:A DNA Mismatches J. Biol. Chem., August 8, 2003; 278(32): 29587 - 29592. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. A. Pope, S. L. Porello, and S. S. David Escherichia coli Apurinic-Apyrimidinic Endonucleases Enhance the Turnover of the Adenine Glycosylase MutY with G:A Substrates J. Biol. Chem., June 14, 2002; 277(25): 22605 - 22615. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. S. Bernards, J. K. Miller, K. K. Bao, and I. Wong Flipping Duplex DNA Inside Out. A DOUBLE BASE-FLIPPING REACTION MECHANISM BY ESCHERICHIA COLI MutY ADENINE GLYCOSYLASE J. Biol. Chem., May 31, 2002; 277(23): 20960 - 20964. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
X. Li and A-L. Lu Molecular Cloning and Functional Analysis of the MutY Homolog of Deinococcus radiodurans J. Bacteriol., November 1, 2001; 183(21): 6151 - 6158. [Abstract] [Full Text] [PDF]
|
|