Inhibition of ribonuclease A by nucleoside–dibasic acid conjugates Original Research Article

We report the inhibition of the ribonucleolytic activity of ribonuclease A (RNase A) by nucleoside–dibasic acid conjugates for the first time. Agarose gel and precipitation assays show that the spacer length and the pKa of the carboxylic group have an important role in the inhibitory capacity. Kinetic experiments indicate a competitive mode of inhibition with inhibition constant (Ki) value of 132 ± 3 μM for Oxa-aT. Docking studies revealed that the carboxylic group of the most active compounds is within hydrogen bonding distance of His-12, Lys-41 and His-119.