title: Genome-wide analysis of mutagenesis bias and context sensitivity of N-methyl-N'-nitro-N-nitrosoguanidine (NTG).
abstract: We have analyzed the mutation spectrum of N-methyl-N'-nitro-N-nitrosoguanidine (NTG) from a set of 4099 mutations identified from whole-genome sequencing of 32 E. coli strains mutagenized with NTG. These data permit precise measurement of NTG's bias for G/C to A/T transitions (96.6% of all mutations) and also show that NTG mutagenesis is strongly sensitive to context, favoring guanine residues preceded by purines by five-fold over those preceded by pyrimidines. These data give confident estimates for the GC bias and transition/transversion ratios of NTG mutagenesis, which could not be estimated confidently from previous, much smaller datasets.
authors.affiliation: University of California, Los Angeles, CA 90095-1570, USA. marcharper@ucla.edu
authors.forename: Marc
authors.initials: M
authors.lastname: Harper
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Lee
mesh_terms: D001483:Base Sequence; D004926:Escherichia coli / Q000235:genetics*; D016680:Genome, Bacterial; D008769:Methylnitronitrosoguanidine / Q000633:toxicity*; D016296:Mutagenesis; D015983:Selection Bias
chemical_list: D008769:Methylnitronitrosoguanidine