Identification of lysine residues in the binding domain of ribonuclease A for the RNase inhibitor from human placenta.

摘要: Abstract Amidination of the available lysine residues complex between RNase A and human placental inhibitor has been performed with methyl acetimidate; conditions derivatization preserve functionally intact. Resistance epsilon-acetimidyllysine to hydrolysis by trypsin allowed, after peptide mapping, identification 7, 31, 41, 61, 91 as those which were fully protected from amidination. Lysine residue 37 was partially In presence poly(A), 41 61 amidination, while 37, 91, 104 only protected; enzyme retained full activity. The results permit located in binding domain for inhibitor. This region is not identical with, but does overlap, poly(A).