Functional and biotechnological insights into diglycosidases

MAZZAFERRO LS; BRECCIA JD

BIOCATALYSIS AND BIOTRANSFORMATION

TAYLOR & FRANCIS LTD

Año: 2011 vol. 29 p. 103 - 112

1024-2422

â-Glucosidases are reported to act in an exo-manner and so are unable to hydrolyze the bond if another sugar is attached to a non-reducing terminus of glucose. Endo-â-glucosidases recognizing the heterosidic linkage were discovered eight decades ago by plant physiologists. However, quite a few were described in detail only recently.  Because of the ability of these enzymes to split a disaccharide off they were named disaccharide-specific glycosidases or “diglycosidases”.  In contrast with the sequential mechanisms of two monoglycosidases, the transformation of some secondary metabolites in one step was reported as responsible for the production of toxic compounds involved in plant defense mechanisms against herbivores, such as hydrogen cyanide. Nowadays, focus of interest has been placed in their unique substrate specificity, for biotransformation of plant based foods. Four activities have been described and characterized so far recognizing the following disaccharidic sugar moieties: primeverose, acuminose, rutinose and vicianose. Moreover, three of the proteins were fully sequenced and one was site-directed mutated in search of the molecular basis of the substrate recognition. This article reviews the role of these enzymes in plant and filamentous fungi, as well as their prospective technological applications.