Catalysis by nucleoside hydrolases.

Wim Versées; Jan Steyaert

doi:10.1016/j.sbi.2003.10.002

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Catalysis by nucleoside hydrolases.

Wim Versées·Jan Steyaert

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Abstract

Nucleoside hydrolases cleave the N-glycosidic bond of ribonucleosides. Because of their vital role in the protozoan purine salvage pathway, nucleoside hydrolases from parasitic protozoa in particular have been studied extensively by X-ray crystallography, kinetic methods and site-directed mutagenesis. An elaborate network of conserved interactions between the metalloenzyme and the ribose enables steric and electrostatic stabilisation of the oxocarbenium-ion-like transition state. Activation of the leaving group by protonation before the formation of the transition state is a recurring catalytic strategy of enzymes that cleave N-glycosidic bonds. However, the mechanisms underlying leaving group activation are still the subject of debate for the nucleoside hydrolases.

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Binding Sites Catalysis Enzyme Activation N-Glycosyl Hydrolases Protein Binding Protein Conformation Protein Folding Ribose Structural Homology, Protein Structure-Activity Relationship Substrate Specificity Journal Article Review

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Wim Versées, Jan Steyaert. 2003. Catalysis by nucleoside hydrolases.. https://doi.org/10.1016/j.sbi.2003.10.002

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