(original) (raw)

TY - JOUR AU - Bebenek, Anna AU - Pietrzykowska, Irena PY - 1996 DA - 1996/04/01 TI - TheisfA mutation inhibits mutator activity and processing of UmuD protein inEscherichia coli recA730 strains JO - Molecular and General Genetics MGG SP - 674 EP - 680 VL - 250 IS - 6 AB - Further studies on theisfA mutation responsible for anti-SOS and antimutagenic activities inEscherichia coli are described. We have previously shown that theisfA mutation inhibits mutagenesis and other SOS-dependent phenomena, possibly by interfering with RecA coprotease activity. TheisfA mutation has now been demonstrated also to suppress mutator activity inE. coli recA730 andrecA730 lexA51(Def) strains that constitutively express RecA coprotease activity. We further show that the antimutator activity of theisfA mutation is related to inhibition of RecA coprotease-dependent processing of UmuD. Expression of UmuD' from plasmid pGW2122 efficiently restores UV-induced mutagenesis in therecA730 isfA strain and partially restores its mutator activity. On the other hand, overproduction of UmuD'C proteins from pGW2123 plasmid markedly enhances UV sensitivity with no restoration of mutability. SN - 1432-1874 UR - https://doi.org/10.1007/BF02172978 DO - 10.1007/BF02172978 ID - Bebenek1996 ER -