Specific uridine binding by some proteins.

Chemically pure or highly purified proteins have been analysed for their specific uridine binding. The peptides generally have two well distinguishable binding sites for uridine regarding their Kd and Bmax values. Uracil competed for the uridine binding sites with uridine, whereas adenine, corticosterone and testosterone did not. The adenine and the sexual steroids augmented the number of maximal binding sites in many cases. The number of specific binding sites varied from 1 to 61 per peptide (Kd: 1.1--51.7 X 10(-10) M).