Design of zinc binding functions for carbonic anhydrase inhibitors

Zinc ion plays a crucial role in the protein's functions and is linked to a variety of physiological processes. It constitutes an essential component of numerous enzymes especially carbonic anhydrase (CAs, EC 4.2.1.1), a pharmaceutically-important metalloprotein which catalyses efficiently the reversible hydration of carbon dioxide to bicarbonate with discharge of a proton. The potential therapeutic applications of selective carbonic anhydrase inhibitors has become an important challenge over the last few years, as some isoforms of this enzyme on the 16 described in higher vertebrates have been found to be involved in important pathologies such as cancer, obesity and ophthalmologic diseases. Coordination of the inhibitor with the zinc ion present in the active site is an important determinant which has to be taken into consideration for the design of isozyme-specific and organ-selective inhibitors. Besides the well known sulfonamide function, others zinc binding groups have been described constituting a new platform for the development of novel pharmacological agents. In this review, recent studies on the discovery of new zinc binding function will be discussed.