New mutations in and around the L2 disordered loop of the RecA protein modulate recombination and/or coprotease activity.

摘要: The RecA protein plays a key role in Escherichia coli recombination and DNA repair. We have created new recA mutants with mutations the vicinity of recA430 mutation (Gly-204----Ser) which is known to affect coprotease activity. Mutants carrying recA659 or recA611, located 3 7 amino acids downstream residue 204, respectively, lose all activities, while mutant recA616, at 12 from this residue, keeps activity but unable promote recombination. Complementation experiments show that both recA611 are dominant over wild-type allele recA616 seems be recessive recA+ recA430. It suggested these domains direct conformational modifications.