Inherent stereospecificity in the reaction of aflatoxin B(1) 8,9-epoxide with deoxyguanosine and efficiency of DNA catalysis.
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ABSTRACT:
SUBMITTER: Brown KL
PROVIDER: S-EPMC3141577 | biostudies-literature | 2009 May
REPOSITORIES: biostudies-literature
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Inherent stereospecificity in the reaction of aflatoxin B(1) 8,9-epoxide with deoxyguanosine and efficiency of DNA catalysis.
Brown Kyle L KL Bren Urban U Stone Michael P MP Guengerich F Peter FP
Chemical research in toxicology 20090501 5
Kinetic analysis of guanine alkylation by aflatoxin B(1) exo-8,9-epoxide, the reactive form of the hepatocarcinogen aflatoxin B(1), shows the reaction to be >2000 times more efficient in DNA than in aqueous solution, that is, with free 2'-deoxyguanosine. Thermodynamic analysis reveals AFB(1) exo-8,9-epoxide intercalation as the predominant source of the observed DNA catalytic effect. However, the known exo > endo epoxide stereospecificity of the DNA alkylation is observed even with free deoxygua ...[more]
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