Fluorine nmr studies of poly(N‐acryloyl‐β‐alanine)–α‐chymotrypsin conjugates

Abstract

SynopsisFluorine nmr experiments carried out at 51.0 and 94.1 MHz have been used to explore the interaction of the probe molecule p-fluorocinnamate with conjugates formed from a-chymotrypsin and poly(N-acryloyl-@-alanine). The data obtained include enzyme-induced chemical-shift effects, spin-lattice (R1) and transverse (Rz) relaxation rates, and the rate constant for dissociation of the fluorocinnamate+nzyme complexes. Analysis of the results indicates that while overall molecular tumbling of the enzyme molecule is not greatly changed by attachment of polymers of various sizes, conjugated polymer can appreciably affect the structure of the p-fluorocinnamate binding site. The important variable involved in such structural changes appears to be the amount of polymer present per mole of protein.