Catalysis allosteric regulation

Montero-Moran GM, Lara-Gonzalez S, Alvarez-Anorve LI et al (2001) On the multiple functional roles of the active site histidine in catalysis and allosteric regulation of Escherichia coli glucosamine 6-phosphate deaminase. Biochemistry 40 10187-10196... 

According to current understanding, binding by an induced-fit mechanism seems to be a unique property of small-molecule-binding RNA aptamers. This property of aptamers might have inspired the idea of fusing aptamer sequences with known catalytic RNAs to introduce the principle of allosteric regulation into ribozyme catalysis. None of the ribo-zymes described so far was known to operate as allosteric enzymes in vitro or in vivo. 

Not only does allosteric regnlation have a profound influence on our understanding of biochemical regulation but the concept has considerable biological importance. These two sites within the enzyme, catalytic and allosteric, can evolve independently to provide the most efficient systems for both catalysis and regnlation. 

There are several demonstration cases that successfully reproduce heterotopic allosteric systems. 64-701 Design of homotropic allosteric systems, on the other hand, is more difficult, but more important for the efficient regulation of equilibria and catalysis. 71,72 Here we introduce several examples of four different allosteric systems, designed mainly with regard to sugar recognition. 

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