... report intensive studies on the direct interactions of Plasmo-dium FabG and Plasmodium ACP in solution, in the presence and absence of its cofactor, NADPH, by monitoring the change in intrinsic fluorescence of ... number of cofactor-binding sites decreased in the presence of PfACP, the affinity of PfFabG for NADPH increased,indicating a negative, heterotropic cooperative effect of PfACP upon binding of NADPH. ... to two,whereas in all PfFabG mutants examined exceptR187K, the number of binding sites remained thesame, with decreased binding of the PfFabG mutants to PfACP in the presence of NADPH (Table...