Skip to main content
NCBI home page
Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1996 Feb 20;93(4):1535–1539. doi: 10.1073/pnas.93.4.1535

Mutational properties of the primary aflatoxin B1-DNA adduct.

E A Bailey 1, R S Iyer 1, M P Stone 1, T M Harris 1, J M Essigmann 1
PMCID: PMC39975  PMID: 8643667

Abstract

The mutagenic activity of the major DNA adduct formed by the liver carcinogen aflatoxin B1 (AFB1) was investigated in vivo. An oligonucleotide containing a single 8,9-dihydro-8-(N7-guanyl)-9-hydroxyaflatoxin B1 (AFB1-N7-Gua) adduct was inserted into the single-stranded genome of bacteriophage M13. Replication in SOS-induced Escherichia coli yielded a mutation frequency for AFB1-N7-Gua of 4%. The predominant mutation was G --> T, identical to the principal mutation in human liver tumors believed to be induced by aflatoxin. The G --> T mutations of AFB1-N7-Gua, unlike those (if the AFB1-N7-Gua-derived apurinic site, were much more strongly dependent on MucAB than UmuDC, a pattern matching that in intact cells treated with the toxin. It is concluded that the AFB1-N7-Gua adduct, and not the apurinic site, has genetic requirements for mutagenesis that best explain mutations in aflatoxin-treated cells. While most mutations were targeted to the site of the lesion, a significant fraction (13%) occurred at the base 5' to the modified guanine. In contrast, the apurinic site-containing genome gave rise only to targeted mutations. The mutational asymmetry observed for AFB1-N7-Gua is consistent with structural models indicating that the aflatoxin moiety of the aflatoxin guanine adduct is covalently intercalated on the 5' face of the guanine residue. These results suggest a molecular mechanism that could explain an important step in the carcinogenicity of aflatoxin B1.

Full text

PDF
1535

Images in this article

1537Fig. 2
on p.1537
1538Fig. 4
on p.1538

Selected References

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

  1. Aguilar F., Hussain S. P., Cerutti P. Aflatoxin B1 induces the transversion of G-->T in codon 249 of the p53 tumor suppressor gene in human hepatocytes. Proc Natl Acad Sci U S A. 1993 Sep 15;90(18):8586–8590. doi: 10.1073/pnas.90.18.8586. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Banerjee S. K., Borden A., Christensen R. B., LeClerc J. E., Lawrence C. W. SOS-dependent replication past a single trans-syn T-T cyclobutane dimer gives a different mutation spectrum and increased error rate compared with replication past this lesion in uninduced cells. J Bacteriol. 1990 Apr;172(4):2105–2112. doi: 10.1128/jb.172.4.2105-2112.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Basu A. K., Wood M. L., Niedernhofer L. J., Ramos L. A., Essigmann J. M. Mutagenic and genotoxic effects of three vinyl chloride-induced DNA lesions: 1,N6-ethenoadenine, 3,N4-ethenocytosine, and 4-amino-5-(imidazol-2-yl)imidazole. Biochemistry. 1993 Nov 30;32(47):12793–12801. doi: 10.1021/bi00210a031. [DOI] [PubMed] [Google Scholar]
  4. Benasutti M., Ejadi S., Whitlow M. D., Loechler E. L. Mapping the binding site of aflatoxin B1 in DNA: systematic analysis of the reactivity of aflatoxin B1 with guanines in different DNA sequences. Biochemistry. 1988 Jan 12;27(1):472–481. doi: 10.1021/bi00401a068. [DOI] [PubMed] [Google Scholar]
  5. Bressac B., Kew M., Wands J., Ozturk M. Selective G to T mutations of p53 gene in hepatocellular carcinoma from southern Africa. Nature. 1991 Apr 4;350(6317):429–431. doi: 10.1038/350429a0. [DOI] [PubMed] [Google Scholar]
  6. Croy R. G., Essigmann J. M., Reinhold V. N., Wogan G. N. Identification of the principal aflatoxin B1-DNA adduct formed in vivo in rat liver. Proc Natl Acad Sci U S A. 1978 Apr;75(4):1745–1749. doi: 10.1073/pnas.75.4.1745. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Croy R. G., Wogan G. N. Quantitative comparison of covalent aflatoxin-DNA adducts formed in rat and mouse livers and kidneys. J Natl Cancer Inst. 1981 Apr;66(4):761–768. [PubMed] [Google Scholar]
  8. Croy R. G., Wogan G. N. Temporal patterns of covalent DNA adducts in rat liver after single and multiple doses of aflatoxin B1. Cancer Res. 1981 Jan;41(1):197–203. [PubMed] [Google Scholar]
  9. Essigmann J. M., Croy R. G., Nadzan A. M., Busby W. F., Jr, Reinhold V. N., Büchi G., Wogan G. N. Structural identification of the major DNA adduct formed by aflatoxin B1 in vitro. Proc Natl Acad Sci U S A. 1977 May;74(5):1870–1874. doi: 10.1073/pnas.74.5.1870. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Essigmann J. M., Green C. L., Croy R. G., Fowler K. W., Büchi G. H., Wogan G. N. Interactions of aflatoxin B1 and alkylating agents with DNA: structural and functional studies. Cold Spring Harb Symp Quant Biol. 1983;47(Pt 1):327–337. doi: 10.1101/sqb.1983.047.01.038. [DOI] [PubMed] [Google Scholar]
  11. Foster P. L., Eisenstadt E., Miller J. H. Base substitution mutations induced by metabolically activated aflatoxin B1. Proc Natl Acad Sci U S A. 1983 May;80(9):2695–2698. doi: 10.1073/pnas.80.9.2695. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Foster P. L., Groopman J. D., Eisenstadt E. Induction of base substitution mutations by aflatoxin B1 is mucAB dependent in Escherichia coli. J Bacteriol. 1988 Aug;170(8):3415–3420. doi: 10.1128/jb.170.8.3415-3420.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Gopalakrishnan S., Harris T. M., Stone M. P. Intercalation of aflatoxin B1 in two oligodeoxynucleotide adducts: comparative 1H NMR analysis of d(ATCAFBGAT).d(ATCGAT) and d(ATAFBGCAT)2. Biochemistry. 1990 Nov 20;29(46):10438–10448. doi: 10.1021/bi00498a002. [DOI] [PubMed] [Google Scholar]
  14. Groopman J. D., Croy R. G., Wogan G. N. In vitro reactions of aflatoxin B1-adducted DNA. Proc Natl Acad Sci U S A. 1981 Sep;78(9):5445–5449. doi: 10.1073/pnas.78.9.5445. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Harris C. C. Chemical and physical carcinogenesis: advances and perspectives for the 1990s. Cancer Res. 1991 Sep 15;51(18 Suppl):5023s–5044s. [PubMed] [Google Scholar]
  16. Hauser J., Levine A. S., Ennis D. G., Chumakov K. M., Woodgate R. The enhanced mutagenic potential of the MucAB proteins correlates with the highly efficient processing of the MucA protein. J Bacteriol. 1992 Nov;174(21):6844–6851. doi: 10.1128/jb.174.21.6844-6851.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Hsu I. C., Metcalf R. A., Sun T., Welsh J. A., Wang N. J., Harris C. C. Mutational hotspot in the p53 gene in human hepatocellular carcinomas. Nature. 1991 Apr 4;350(6317):427–428. doi: 10.1038/350427a0. [DOI] [PubMed] [Google Scholar]
  18. Kaden D. A., Call K. M., Leong P. M., Komives E. A., Thilly W. G. Killing and mutation of human lymphoblast cells by aflatoxin B1: evidence for an inducible repair response. Cancer Res. 1987 Apr 15;47(8):1993–2001. [PubMed] [Google Scholar]
  19. Lasko D. D., Harvey S. C., Malaikal S. B., Kadlubar F. F., Essigmann J. M. Specificity of mutagenesis by 4-aminobiphenyl. A possible role for N-(deoxyadenosin-8-yl)-4-aminobiphenyl as a premutational lesion. J Biol Chem. 1988 Oct 25;263(30):15429–15435. [PubMed] [Google Scholar]
  20. Lawrence C. W., Borden A., Banerjee S. K., LeClerc J. E. Mutation frequency and spectrum resulting from a single abasic site in a single-stranded vector. Nucleic Acids Res. 1990 Apr 25;18(8):2153–2157. doi: 10.1093/nar/18.8.2153. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Levy D. D., Groopman J. D., Lim S. E., Seidman M. M., Kraemer K. H. Sequence specificity of aflatoxin B1-induced mutations in a plasmid replicated in xeroderma pigmentosum and DNA repair proficient human cells. Cancer Res. 1992 Oct 15;52(20):5668–5673. [PubMed] [Google Scholar]
  22. Lin J. K., Miller J. A., Miller E. C. 2,3-Dihydro-2-(guan-7-yl)-3-hydroxy-aflatoxin B1, a major acid hydrolysis product of aflatoxin B1-DNA or -ribosomal RNA adducts formed in hepatic microsome-mediated reactions and in rat liver in vivo. Cancer Res. 1977 Dec;37(12):4430–4438. [PubMed] [Google Scholar]
  23. Loeb L. A., Preston B. D. Mutagenesis by apurinic/apyrimidinic sites. Annu Rev Genet. 1986;20:201–230. doi: 10.1146/annurev.ge.20.120186.001221. [DOI] [PubMed] [Google Scholar]
  24. Mackay W., Benasutti M., Drouin E., Loechler E. L. Mutagenesis by (+)-anti-B[a]P-N2-Gua, the major adduct of activated benzo[a]pyrene, when studied in an Escherichia coli plasmid using site-directed methods. Carcinogenesis. 1992 Aug;13(8):1415–1425. doi: 10.1093/carcin/13.8.1415. [DOI] [PubMed] [Google Scholar]
  25. Martin C. N., Garner R. C. Aflatoxin B -oxide generated by chemical or enzymic oxidation of aflatoxin B1 causes guanine substitution in nucleic acids. Nature. 1977 Jun 30;267(5614):863–865. doi: 10.1038/267863a0. [DOI] [PubMed] [Google Scholar]
  26. McMahon G., Davis E. F., Huber L. J., Kim Y., Wogan G. N. Characterization of c-Ki-ras and N-ras oncogenes in aflatoxin B1-induced rat liver tumors. Proc Natl Acad Sci U S A. 1990 Feb;87(3):1104–1108. doi: 10.1073/pnas.87.3.1104. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. McNally K. P., Freitag N. E., Walker G. C. LexA-independent expression of a mutant mucAB operon. J Bacteriol. 1990 Nov;172(11):6223–6231. doi: 10.1128/jb.172.11.6223-6231.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Meeker A. L., Li Y. K., Shortle D., Stites W. E. A simplified protocol for isolation and characterization of ssM13 DNA templates for use in dideoxy sequencing. Biotechniques. 1993 Sep;15(3):370–372. [PubMed] [Google Scholar]
  29. Messing J. New M13 vectors for cloning. Methods Enzymol. 1983;101:20–78. doi: 10.1016/0076-6879(83)01005-8. [DOI] [PubMed] [Google Scholar]
  30. Miller E. C. Some current perspectives on chemical carcinogenesis in humans and experimental animals: Presidential Address. Cancer Res. 1978 Jun;38(6):1479–1496. [PubMed] [Google Scholar]
  31. Muench K. F., Misra R. P., Humayun M. Z. Sequence specificity in aflatoxin B1--DNA interactions. Proc Natl Acad Sci U S A. 1983 Jan;80(1):6–10. doi: 10.1073/pnas.80.1.6. [DOI] [PMC free article] [PubMed] [Google Scholar]
  32. Refolo L. M., Bennett C. B., Humayun M. Z. Mechanisms of frameshift mutagenesis by aflatoxin B1-2,3-dichloride. J Mol Biol. 1987 Feb 20;193(4):609–636. doi: 10.1016/0022-2836(87)90344-5. [DOI] [PubMed] [Google Scholar]
  33. Sahasrabudhe S., Sambamurti K., Humayun M. Z. Mutagenesis by aflatoxin in M13 DNA: base-substitution mechanisms and the origin of strand bias. Mol Gen Genet. 1989 May;217(1):20–25. doi: 10.1007/BF00330937. [DOI] [PubMed] [Google Scholar]
  34. Sambamurti K., Callahan J., Luo X., Perkins C. P., Jacobsen J. S., Humayun M. Z. Mechanisms of mutagenesis by a bulky DNA lesion at the guanine N7 position. Genetics. 1988 Dec;120(4):863–873. doi: 10.1093/genetics/120.4.863. [DOI] [PMC free article] [PubMed] [Google Scholar]
  35. Soman N. R., Wogan G. N. Activation of the c-Ki-ras oncogene in aflatoxin B1-induced hepatocellular carcinoma and adenoma in the rat: detection by denaturing gradient gel electrophoresis. Proc Natl Acad Sci U S A. 1993 Mar 1;90(5):2045–2049. doi: 10.1073/pnas.90.5.2045. [DOI] [PMC free article] [PubMed] [Google Scholar]
  36. Swenson D. H., Lin J. K., Miller E. C., Miller J. A. Aflatoxin B1-2,3-oxide as a probable intermediate in the covalent binding of aflatoxins B1 and B2 to rat liver DNA and ribosomal RNA in vivo. Cancer Res. 1977 Jan;37(1):172–181. [PubMed] [Google Scholar]
  37. Trottier Y., Waithe W. I., Anderson A. Kinds of mutations induced by aflatoxin B1 in a shuttle vector replicating in human cells transiently expressing cytochrome P4501A2 cDNA. Mol Carcinog. 1992;6(2):140–147. doi: 10.1002/mc.2940060209. [DOI] [PubMed] [Google Scholar]
  38. Walker G. C. Isolation and characterization of mutants of the plasmid pKM101 deficient in their ability to enhance mutagenesis and repair. J Bacteriol. 1978 Mar;133(3):1203–1211. doi: 10.1128/jb.133.3.1203-1211.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
  39. Wood M. L., Dizdaroglu M., Gajewski E., Essigmann J. M. Mechanistic studies of ionizing radiation and oxidative mutagenesis: genetic effects of a single 8-hydroxyguanine (7-hydro-8-oxoguanine) residue inserted at a unique site in a viral genome. Biochemistry. 1990 Jul 31;29(30):7024–7032. doi: 10.1021/bi00482a011. [DOI] [PubMed] [Google Scholar]

Articles from Proceedings of the National Academy of Sciences of the United States of America are provided here courtesy of National Academy of Sciences

RESOURCES