Biopolymers and cell. 1997; 13 (6): 493 - 496

Genetic mechanisms of the resistance of Escherichia coli to amino acid antimetabolites. 2. Study of the frequency of induction and properties of glyphosate resistant mutants

E. Cherepenko

The frequency of the induction by nttrosoguanidine of glyphosate resistant mutants was compared for recipient and donor, as well as for iysogenic and non-lysogenic E. coli cells. It was found that integration of viral genomes and also larger replicons such as F-factor into host chromosome increased the level of glyphosate resistance by the factor ranging from 1.6 to 6. Mutants tolerating 0.2 rnM of the inhibitor were obtained one order of magnitude more frequently than mutants tolerating I mM of this inhibitor. One half of the mutants of every group were resistant not only to the analogue of glycine,but also to the analogue of lysine. An attempt to clone an insertion from a gene library of one of the mutants was attempted but failed. Study on the nature of this gene is in progress.