Initiation of DNA replication in Δcya mutants of escherichia coli K12

摘要

The purified DnaA protein has a high affinity for cyclic AMP(Camp). Using equilibrium dialysis, we determined the K_A value for cAMP as 0.819μM~-1. The number of cAMP binding sites DnaA protein molecule was calculated to be 1.04. This binding was quite specific for aCMP. ATP was also bound by DnaA protein and inhibited cAMP binding. This inhibition was non-competitive in nature with an inhibition constant(K_i)of about 8.25μM.