Abstract
Three molecular species of methyl-accepting proteins exist in Bacillus subtilis cells, which collect methyl groups from methylated DNA. A 20-kilodalton (kDa) protein was constitutively present in the cells of the ada+ (proficient in adaptive response) strain as well as in those of six ada (deficient in adaptive response) mutant strains and was assigned to the O6-methylguanine:DNA methyltransferase. Another species of O6-methylguanine:DNA methyltransferase, which had a molecular size of 22 kDa, emerged after adaptive treatment of the ada+ but not any of the ada mutant cells. A 27-kDa methyl-accepting protein, which preferred methylated poly(dT) to methylated calf thymus DNA as a substrate, was assigned to the methylphosphotriester:DNA methyltransferase. It was produced, after adaptive treatment, in the cells of ada+, ada-3, ada-4, and ada-6 strains but not in the cells of ada-1, ada-2, or ada-5 strains. These results support and extend our proposition that ada mutants can be classified into two groups; one (the ada-4 group) is defective only in the inducible synthesis of O6-methylguanine:DNA methyltransferase (22-kDa protein), and the other (the ada-1 group) is deficient in the adaptive response in toto. The finding that inducible and constitutive methyltransferases reside in different molecular species of methyl-accepting proteins is intriguing compared with the regulatory mechanisms of the adaptive response to simple alkylating agents in other organisms.
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Selected References
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- Demple B., Jacobsson A., Olsson M., Robins P., Lindahl T. Repair of alkylated DNA in Escherichia coli. Physical properties of O6-methylguanine-DNA methyltransferase. J Biol Chem. 1982 Nov 25;257(22):13776–13780. [PubMed] [Google Scholar]
- 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]
- Hadden C. T., Foote R. S., Mitra S. Adaptive response of Bacillus subtilis to N-methyl-N'-nitro-N-nitrosoguanidine. J Bacteriol. 1983 Feb;153(2):756–762. doi: 10.1128/jb.153.2.756-762.1983. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Jeggo P. Isolation and characterization of Escherichia coli K-12 mutants unable to induce the adaptive response to simple alkylating agents. J Bacteriol. 1979 Sep;139(3):783–791. doi: 10.1128/jb.139.3.783-791.1979. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Karran P., Hjelmgren T., Lindahl T. Induction of a DNA glycosylase for N-methylated purines is part of the adaptive response to alkylating agents. Nature. 1982 Apr 22;296(5859):770–773. doi: 10.1038/296770a0. [DOI] [PubMed] [Google Scholar]
- Karran P., Lindahl T., Griffin B. Adaptive response to alkylating agents involves alteration in situ of O6-methylguanine residues in DNA. Nature. 1979 Jul 5;280(5717):76–77. doi: 10.1038/280076a0. [DOI] [PubMed] [Google Scholar]
- 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]
- Lemotte P. K., Walker G. C. Induction and autoregulation of ada, a positively acting element regulating the response of Escherichia coli K-12 to methylating agents. J Bacteriol. 1985 Mar;161(3):888–895. doi: 10.1128/jb.161.3.888-895.1985. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 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]
- McCarthy J. G., Edington B. V., Schendel P. F. Inducible repair of phosphotriesters in Escherichia coli. Proc Natl Acad Sci U S A. 1983 Dec;80(24):7380–7384. doi: 10.1073/pnas.80.24.7380. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 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]
- Mitra S., Pal B. C., Foote R. S. O6-methylguanine-DNA methyltransferase in wild-type and ada mutants of Escherichia coli. J Bacteriol. 1982 Oct;152(1):534–537. doi: 10.1128/jb.152.1.534-537.1982. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Morohoshi F., Munakata N. Bacillus subtilis mutants deficient in the adaptive response to simple alkylating agents. J Bacteriol. 1985 Mar;161(3):825–830. doi: 10.1128/jb.161.3.825-830.1985. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Morohoshi F., Munakata N. Two classes of Bacillus subtilis mutants deficient in the adaptive response to simple alkylating agents. Mol Gen Genet. 1986 Feb;202(2):200–206. doi: 10.1007/BF00331637. [DOI] [PubMed] [Google Scholar]
- Nakabeppu Y., Kondo H., Kawabata S., Iwanaga S., Sekiguchi M. Purification and structure of the intact Ada regulatory protein of Escherichia coli K12, O6-methylguanine-DNA methyltransferase. J Biol Chem. 1985 Jun 25;260(12):7281–7288. [PubMed] [Google Scholar]
- Nakabeppu Y., Sekiguchi M. Regulatory mechanisms for induction of synthesis of repair enzymes in response to alkylating agents: ada protein acts as a transcriptional regulator. Proc Natl Acad Sci U S A. 1986 Sep;83(17):6297–6301. doi: 10.1073/pnas.83.17.6297. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Olsson M., Lindahl T. Repair of alkylated DNA in Escherichia coli. Methyl group transfer from O6-methylguanine to a protein cysteine residue. J Biol Chem. 1980 Nov 25;255(22):10569–10571. [PubMed] [Google Scholar]
- Robins P., Cairns J. Quantitation of the adaptive response to alkylating agents. Nature. 1979 Jul 5;280(5717):74–76. doi: 10.1038/280074a0. [DOI] [PubMed] [Google Scholar]
- Schendel P. F., Robins P. E. Repair of O6-methylguanine in adapted Escherichia coli. Proc Natl Acad Sci U S A. 1978 Dec;75(12):6017–6020. doi: 10.1073/pnas.75.12.6017. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 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]
- Spizizen J. TRANSFORMATION OF BIOCHEMICALLY DEFICIENT STRAINS OF BACILLUS SUBTILIS BY DEOXYRIBONUCLEATE. Proc Natl Acad Sci U S A. 1958 Oct 15;44(10):1072–1078. doi: 10.1073/pnas.44.10.1072. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 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]
- Teo I., Sedgwick B., Kilpatrick M. W., McCarthy T. V., Lindahl T. The intracellular signal for induction of resistance to alkylating agents in E. coli. Cell. 1986 Apr 25;45(2):315–324. doi: 10.1016/0092-8674(86)90396-x. [DOI] [PubMed] [Google Scholar]
- 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]