[A comparative analysis of UMUDC-dependent induction of tandem duplications, point and insertional reversions in Salmonella].

Comparative analysis of UV induction of tandem chromosome (Mtc+) duplications and reversions of point mutations (base pair substitutions) and of insertion mutations (precise excision of Tn10) was carried out. Salmonella (umuST) genes deficiency preventing dose-dependent UV induction of point mutation reversion were shown to have a less pronounced effect on the induction of tandem chromosome duplications. UV induction of tandem chromosome duplications is similar to UV induction of insertion mutation reversion: dose-dependent UV induction of both occurs in umuST Salmonella strains. E. coli umuDC+ genes included in Salmonella genome appreciably enhance the UV induction of both tandem duplications and insertion mutation reversion. The presence of umuDC+ genes ensures an expressed dose-dependent UV induction of point mutation reversion.