A Single Amino Acid Residue Determines the Ratio of Hydrolysis to Transglycosylation Catalyzed by β-Glucosidases

Title:A Single Amino Acid Residue Determines the Ratio of Hydrolysis to Transglycosylation Catalyzed by β-Glucosidases

Volume: 20 Issue: 1

Author(s): M.A. Frutuoso and S.R. Marana

Affiliation:

Keywords: β-glucosidases, glycoside hydrolases, oligosaccharides synthesis, Spodoptera frugiperda, Tenebrio molitor, transglycosylation, substrate

Abstract: The propensity to catalysis of transglycosylation of the β-glucosidase Tmβgly is higher than for Sfβgly. Moreover the propensity to catalysis of transglycosylation is directly proportional to the substrate concentration for Tmβgly, whereas for Sfβgly it is constant. For instance, 60% of a Tmβgly sample catalyzes transglycosylation reactions at 40 mM p-nitrophenyl β-glucoside, whereas only 40% is engaged in hydrolysis of this substrate. For Sfβgly the fraction involved in transglycosylation is only 30 %. In addition, 48 % of a Tmβgly sample catalyzes transglycosylation reactions at 8 mM methylumbelliferyl β-glucoside, whereas Sfβgly does not catalyze transglycosylation using this substrate. Interestingly, these Tmβgly properties were grafted into Sfβgly by a single replacement of a residue forming a channel involved in supplying the catalytic water molecules for attack on the covalent intermediate present in the reaction catalyzed by β-glucosidases. Hence a single residue determines the ratio of hydrolysis to transglycosylation reactions catalyzed by these β-glucosidases.

Cite this article as:

Frutuoso M.A. and Marana S.R., A Single Amino Acid Residue Determines the Ratio of Hydrolysis to Transglycosylation Catalyzed by β-Glucosidases, Protein & Peptide Letters 2013; 20 (1) . https://dx.doi.org/10.2174/0929866511307010102

DOI https://dx.doi.org/10.2174/0929866511307010102	Print ISSN 0929-8665
Publisher Name Bentham Science Publisher	Online ISSN 1875-5305