Skip to main content
Nucleic Acids Research logoLink to Nucleic Acids Research
. 1989 Nov 11;17(21):8475–8484. doi: 10.1093/nar/17.21.8475

Purification of the E. coli ogt gene product to homogeneity and its rate of action on O6-methylguanine, O6-ethylguanine and O4-methylthymine in dodecadeoxyribonucleotides.

M C Wilkinson 1, P M Potter 1, L Cawkwell 1, P Georgiadis 1, D Patel 1, P F Swann 1, G P Margison 1
PMCID: PMC335020  PMID: 2685744

Abstract

The E. coli gene ogt encodes the DNA repair protein O6-alkylguanine-DNA-alkyltransferase (O6-AlkG ATase). The protein coding region of the gene was cloned into a multicopy expression vector to obtain high yields of the enzyme (approximately 0.2% of total protein) which was purified to apparent homogeneity by affinity, molecular exclusion and reverse-phase chromatography. Good correlation was found between the determined and predicted amino acid compositions. The ability of the purified protein to act on O6-methylguanine (O6-MeG), O6-ethylguanine (O6-EtG) and O4-methylthymine (O4-MeT) in self-complementary dodecadeoxyribonucleotides was compared to that of 19 kDa fragment of the related ada-protein. With both proteins the rate order was O6-MeG greater than O6-EtG greater than O4-MeT, however, the ogt protein was found to repair O6-MeG, O6-EtG and O4-Met, 1.1, 173 and 84 times, respectively, faster than the ada protein.

Full text

PDF
8482

Images in this article

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Brennand J., Margison G. P. Expression in mammalian cells of a truncated Escherichia coli gene coding for O6-alkylguanine alkyltransferase reduces the toxic effects of alkylating agents. Carcinogenesis. 1986 Dec;7(12):2081–2084. doi: 10.1093/carcin/7.12.2081. [DOI] [PubMed] [Google Scholar]
  2. Brent T. P., Dolan M. E., Fraenkel-Conrat H., Hall J., Karran P., Laval L., Margison G. P., Montesano R., Pegg A. E., Potter P. M. Repair of O-alkylpyrimidines in mammalian cells: a present consensus. Proc Natl Acad Sci U S A. 1988 Mar;85(6):1759–1762. doi: 10.1073/pnas.85.6.1759. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Demple B., Sedgwick B., Robins P., Totty N., Waterfield M. D., Lindahl T. Active site and complete sequence of the suicidal methyltransferase that counters alkylation mutagenesis. Proc Natl Acad Sci U S A. 1985 May;82(9):2688–2692. doi: 10.1073/pnas.82.9.2688. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Graves R. J., Li B. F., Swann P. F. Repair of O6-methylguanine, O6-ethylguanine, O6-isopropylguanine and O4-methylthymine in synthetic oligodeoxynucleotides by Escherichia coli ada gene O6-alkylguanine-DNA-alkyltransferase. Carcinogenesis. 1989 Apr;10(4):661–666. doi: 10.1093/carcin/10.4.661. [DOI] [PubMed] [Google Scholar]
  5. Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
  6. Lawley P. D., Orr D. J. Specific excision of methylation products from DNA of Escherichia coli treated with N-methyl-N'-nitro-N-nitrosoguanidine. Chem Biol Interact. 1970 Aug;2(2):154–157. doi: 10.1016/0009-2797(70)90047-5. [DOI] [PubMed] [Google Scholar]
  7. Li B. F., Reese C. B., Swann P. F. Synthesis and characterization of oligodeoxynucleotides containing 4-O-methylthymine. Biochemistry. 1987 Feb 24;26(4):1086–1093. doi: 10.1021/bi00378a015. [DOI] [PubMed] [Google Scholar]
  8. Lindahl T. DNA repair enzymes. Annu Rev Biochem. 1982;51:61–87. doi: 10.1146/annurev.bi.51.070182.000425. [DOI] [PubMed] [Google Scholar]
  9. Margison G. P., Cooper D. P., Brennand J. Cloning of the E. coli O6-methylguanine and methylphosphotriester methyltransferase gene using a functional DNA repair assay. Nucleic Acids Res. 1985 Mar 25;13(6):1939–1952. doi: 10.1093/nar/13.6.1939. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. McCarthy T. V., Karran P., Lindahl T. Inducible repair of O-alkylated DNA pyrimidines in Escherichia coli. EMBO J. 1984 Mar;3(3):545–550. doi: 10.1002/j.1460-2075.1984.tb01844.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. McCarthy T. V., Lindahl T. Methyl phosphotriesters in alkylated DNA are repaired by the Ada regulatory protein of E. coli. Nucleic Acids Res. 1985 Apr 25;13(8):2683–2698. doi: 10.1093/nar/13.8.2683. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Pegg A. E., Scicchitano D., Dolan M. E. Comparison of the rates of repair of O6-alkylguanines in DNA by rat liver and bacterial O6-alkylguanine-DNA alkyltransferase. Cancer Res. 1984 Sep;44(9):3806–3811. [PubMed] [Google Scholar]
  13. Potter P. M., Wilkinson M. C., Fitton J., Carr F. J., Brennand J., Cooper D. P., Margison G. P. Characterisation and nucleotide sequence of ogt, the O6-alkylguanine-DNA-alkyltransferase gene of E. coli. Nucleic Acids Res. 1987 Nov 25;15(22):9177–9193. doi: 10.1093/nar/15.22.9177. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Samson L., Cairns J. A new pathway for DNA repair in Escherichia coli. Nature. 1977 May 19;267(5608):281–283. doi: 10.1038/267281a0. [DOI] [PubMed] [Google Scholar]
  15. Sedgwick B. Molecular cloning of a gene which regulates the adaptive response to alkylating agents in Escherichia coli. Mol Gen Genet. 1983;191(3):466–472. doi: 10.1007/BF00425764. [DOI] [PubMed] [Google Scholar]
  16. Sedgwick B. Molecular signal for induction of the adaptive response to alkylation damage in Escherichia coli. J Cell Sci Suppl. 1987;6:215–223. doi: 10.1242/jcs.1984.supplement_6.15. [DOI] [PubMed] [Google Scholar]
  17. Singer B., Kuśmierek J. T. Chemical mutagenesis. Annu Rev Biochem. 1982;51:655–693. doi: 10.1146/annurev.bi.51.070182.003255. [DOI] [PubMed] [Google Scholar]
  18. Teo I., Sedgwick B., Demple B., Li B., Lindahl T. Induction of resistance to alkylating agents in E. coli: the ada+ gene product serves both as a regulatory protein and as an enzyme for repair of mutagenic damage. EMBO J. 1984 Sep;3(9):2151–2157. doi: 10.1002/j.1460-2075.1984.tb02105.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Vieira J., Messing J. The pUC plasmids, an M13mp7-derived system for insertion mutagenesis and sequencing with synthetic universal primers. Gene. 1982 Oct;19(3):259–268. doi: 10.1016/0378-1119(82)90015-4. [DOI] [PubMed] [Google Scholar]
  20. Weinfeld M., Drake A. F., Saunders J. K., Paterson M. C. Stereospecific removal of methyl phosphotriesters from DNA by an Escherichia coli ada+ extract. Nucleic Acids Res. 1985 Oct 11;13(19):7067–7077. doi: 10.1093/nar/13.19.7067. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Nucleic Acids Research are provided here courtesy of Oxford University Press

RESOURCES