Nitrous Acid Damage to Duplex Deoxyribonucleic Acid: Distinction Between Deamination of Cytosine Residues and a Novel Mutational Lesiont
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چکیده
The rate of nitrous acid deamination of labeled cytosine residues in native Escherichia coli deoxyribonucleic acid was monitored in vitro by release of acidsoluble counts after treatment with uracil deoxyribonucleic acid glycosylase. The reaction exhibited a lag and was not stimulated by several agents previously shown to enhance base substitution mutagenesis during nitrous acid treatment of duplex deoxyribonucleic acid. We conclude that a significant proportion of nitrous acid induced mutagenic lesions are novel lesions and not cytosine deaminations.
منابع مشابه
Nitrous acid damage to duplex deoxyribonucleic acid: distinction between deamination of cytosine residues and a novel mutational lesion.
The rate of nitrous acid deamination of labeled cytosine residues in native Escherichia coli deoxyribonucleic acid was monitored in vitro by release of acid-soluble counts after treatment with uracil deoxyribonucleic acid glycosylase. The reaction exhibited a lag and was not stimulate by several agents previously shown to enhance base substitution mutagenesis during nitrous acid treatment of du...
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DNA extracted from Novikoff hepatoma cells grown in suspension culture in the presence of [14C]methyl-labeled methionine was hydrolyzed with formic acid-diphenylamine and resultant pyrimidine clusters separated on DEAE-columns at pH 5.2. Clusters containing up to nine adjacent pyrimidines were resolved. Shorter clusters were more scarce and longer clusters more abundant than would be expected o...
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