Structure-activity relationship of the ficin hydrolysis of phenyl hippurates. Comparison with papain, actinidin, and bromelain

Article abstract of DOI:10.1021/jm00377a009

A study of the hydrolysis of 30 substituted-phenyl hippurates by the enzyme ficin has been made. From the results the following quantitative structure-activity relationship (QSAR) has been derived: log 1/K(m) = 0.79π'₃ + 0.58σ + 0.28 MR(4,5) + 3.70. In this expression K(m) is the Michaelis constant, π'₃ refers to the more hydrophobic of the two meta substituents, and MR(4,5) is the molar refractivity of substituents in the 4- and 5-positions of the phenyl ring. This QSAR is compared with those from papain, actinidin, bromelain B, and bromelain D.