Probing enzyme phosphoester interactions by combining mutagenesis and chemical modification of phosphate ester oxygens

This review covers studies that have used sulfur and carbon substitution of phosphate ester oxygens to probe the energetics of protein-ligand interactions, with a deliberate emphasis on enzymatic reactions. Topics discussed include (1) noncovalent interactions with phosphate esters, (2) chemical reactivity of phosphoester, phosphothioester and phosphonoester linkages, (3) free energy analysis, (4) experimental techniques, (5) examples using chemical modification of phosphate esters alone and (6) examples combining chemical modification and mutagenesis.