55] Stabilization of enzymes by intramolecular cross-linking using bifunctional reagents

Abstract

Publisher Summary The problem of enzyme stabilization has received considerable attention in recent years. Enzyme immobilization is used most frequently to solve the problem of enzyme stabilization. However, other methods are also suggested as well. For example, enzyme stabilization has been achieved after (1) addition of low molecular weight compounds to enzymes free in solution, (2) chemical modification of enzymes by substitution with low molecular weight compounds, and (3) use of bifunctional reagents to produce enzymes containing artificial intramolecular cross-links. These methods are desirable in particular when the presence of a support may decrease both the binding capacity and the reactivity of the enzyme. Also, in medical therapy applied enzyme must in many cases interact with receptors or other components of cellular membranes. In this instance, a support may change the key pathways dramatically. This chapter discusses on the stabilization of enzymes through intramolecular crosslinking. The principles of intramolecular crosslinking are presented diagrammatically. This approach is based on diminishing the polypeptide entropy, which is the principal thermodynamic quantity stabilizing the denatured form.