Mechanism glycosidase

Rye CS, Withers SG (2000) Glycosidase mechanisms, CurrOpin Chem Biol 4 573-580 Saito M, Yu RK (1995) Biochemistry and function of sialidases. In Rosenberg A (ed) Biology of the sialic acids. Plenum, NY, pp 261-313... 

D. L. Zechel and S. G. Withers, Glycosidase mechanisms Anatomy of a finely tuned catalyst, Acc. 

Zechel, D.L. and Withers, S.G. (2000) Glycosidase mechanisms anatomy of a finely tuned catalyst. Acc Chem Res, 33, 11-18... 

A. Vasella, G. J. Davies, and M. Bohm, Glycosidase mechanisms, Curr. Opin. Chem. Biol., 6 (2002) 619-629. 

Iminosugars are naturally occurring polyhydroxylated alkaloids,[5] many of them are potent inhibitors of glycosidases and glycosyltransferases (Figure 19.1) [6]. Because of that they have attracted much interest with respect to potential therapeuhc applications [2, 7]. Furthermore, they are useful probes in fundamental biochemical studies of glycosidases mechanism [8]. 

SCHEME 16.2 Glycosidase mechanisms for (a) a retaining a-glycosidase and (b) an inverting a-glycosidase proceeding through an oxocarbenium ion-like intermediate. 

Ren, J., Wang, Y., Dong, Y. and Stuart, D.I. (1994) The yV-glycosidase mechanism of rihosome-inactivating proteins implied by crystal structures of alpha-momorcharin. Structure, 2, 7 16. 

Scheme 3 General glycosidase mechanisms, (a) An inverting /3-glycosidase. (b) A retaining /3-glycosidase proceeding through an intermediate with a 4C1 conformation, (c) Substrate-assisted mechanism.

Figure 1. Retaining glycosidase mechanism showing the transition states of the glycosylation and deglycosylation steps (here illustrated for the hydrolysis of aryl P- lactosides by Tr Cell A).

Vasella A, Davies GJ, Bohm M (2002) Glycosidase mechanism. Curr Opin Chem Biol 6 619-629... 

Briggs, A. J., Evans, C. M., Glenn, R., Kirby, A. J. (1983). Stereoelectronic effects at oxygen. A very large effect on the hydrolysis of a conformationally locked acetal implications for p-glycosidase mechanisms. Journal of the Chemical Society, Perkin Transactions 2, 1637. 

---