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Plasmodium falciparum enolase (Pfeno) is a dimeric enzyme with multiple moonlighting functions. This enzyme is thus a potential target for anti‐malarial treatments. A unique feature of Pfeno is the presence of a pentapeptide insert ¹⁰⁴EWGWS¹⁰⁸. The functional role of tryptophan residues in this insert was investigated using site‐directed mutagenesis. Replacement of these two Trp residues with alanines (or lysines) resulted in a near complete loss of enolase activity and dissociation of the normal dimeric form into monomers. Molecular modeling indicated that ³⁴⁰R forms π‐cation bonds with the aromatic rings of ¹⁰⁵W and ⁴⁶Y. Mutation induced changes in the interactions among these three residues were presumably relayed to the inter‐subunit interface via a coil formed by ⁴⁶Y : ⁵⁹Y, resulting in the disruption of a salt bridge between ¹¹R : ⁴²⁵E and a π‐cation interaction between ¹¹R : ⁵⁹Y. This led to a drop …