Differential Sensitivity to Certain DNA-Damaging Treatments, Including 8-Methoxypsoralen Plus 340 nm Ultraviolet Irradiation, Between K-12 and B/r Strains of Escherichia Coli

• DOI: 10.1007/978-1-4684-4382-0_8
• Publication Date: 2012-07-28T20:30:21Z
• Authors: B. A. Bridges; A. Wright; M. Stannard; E. Moustacchi
• Keywords: DNA, Bacterial; DNA Repair; Species Specificity; Ultraviolet Rays; Mutation; Escherichia coli; Methoxsalen; Intercalating Agents; 3. Good health

For want of information to the contrary, it is usually assumed that when a molecule of a mutagen is near to a molecule of DNA, reaction will occur with a probability that is essentially the same whether or not the DNA is in a bacterial or human chromosome, whether or not it is complexed with proteins, and whatever its degree of superhelicity. A moment’s thought suggests that this assumption is unlikely to be strictly true although it would be a bold man who would predict to what extent chromosomal structure might influence the probability of interaction with mutagens. The present paper records a simple bacterial model where the simplest interpretation of the data suggests that the structure rather than sequence of the DNA seems to affect the probability of interaction with intercalating agents such as 8-methoxypsoralen (8-MOP).