Ureases. II. Properties and their customizing by enzyme immobilizations: A review

Ureases are enzymes highly desirable in immobilized form for a number of applications that exploit urea cleavage and an increase in pH, inherent to the reaction. Major among them are medical and analytical applications, but there have emerged new biotechnological and engineering areas, proving that there exists a growing demand for robust reliable immobilized urease preparations with defined properties. These can be assured by immobilizing the enzymes. By creating disturbance in the original state of enzymes, immobilizations inevitably change enzyme properties, enabling them to be customized for specific applications. In this context. this article offers a review of reports on immobilizations of ureases covering the last two decades. It surveys the immobilization techniques and support materials applied, in addition to the resulting properties of the enzyme's. In this manner it attempts to provide useful guidance through the wealth of available immobilization data in the literature, but more importantly, to develop an integrated perspective on how to customize ureases for their applications, which may help establish rational immobilization procedures in place of tedious experimental optimization. (C) 2009 Elsevier B.V. All rights reserved.