Mutational DNA Base Sequence Changes in Plasmid Damaged at a Specific Region by Ultraviolet Light

Abstract

Plasmid/UV-mutagenesis/Base change/Transition/Pyr(6-4)Pyo photoproduct Mutational nucleotide sequence changes by ultraviolet light (UV) in the gene for Escherichia coli cAMP receptor protein (CRP) were analyzed. Transitions were most the frequent mutations and occurred at pyrimidine-pyrimidine sequences. Most transitions were GC to AT base changes at 3’ cytosine of 5’-pyrimidine-cytosinc-3’ sequences, supporting the concept that pyrimidine(6-4)pyrimidone, Pyr(6-4)Pyo, photoproduct is a principal pre-mutagenic lesion for transition mutations induced by UV. Transversion and frameshift mutations were also found. © 1986, Journal of Radiation Research Editorial Committee. All rights reserved.