8-Glucosidases substrate specificity

The glucosidases involved in the biosynthetic pathway have been studied in detail by Hemscheidt and Zenk 203), and two of the isolated enzymes were specific for the hydrolysis of strictosidine (33) and were purified 120-fold. The enzyme was isolated from a number of indole alkaloid producing plants, including C. roseus, C.pusilus, and C. trichophyllus. The pH optimum was 6.5, and the values were 0.2 mM for enzyme I and 0.1 mM for enzyme II. Molecular weights were estimated at 230,000 for enzyme I and 450,000 for enzyme II. Unlike the case of the enzyme system of Scott et al. 198,199), tryptamine did not activate either of the two enzymes. The enzymes were highly substrate specific vincoside (85)... 

L. Verdoucq, J. Moriniere, D. R. Bevan, A. Esen, A. Vasella, B. Henrissat, and M. Czjzek, Structural determinants of substrate specificity in family 1 P-glucosidases,. /. Biol. Chem., 279 (2004) 31796-31803. 

Substrate Specificity of Enzymes of Saccharomyces cerevisiae Having a-D-Glucosidase Activity"... 

Nucci, R., Moracci. M., Vaccaro, C., Vespa, N., and Rossi M (1993) Exo-glucosidase activity and substrate specificity of the beta-glycosidase isolated from the extreme thermophile Sulfolobus solfataricus, Biotechnology and Applied Biochemistry 17, 239-50. 

Table 3.2 Substrate specificity and localization of cyanogenic j6-glucosidases...

Myrosinases are the only known S-glucosidases. Whereas some myrosinases exhibit a pronounced substrate specificity towards glucosinolates (e.g. MacLeod and Rossiter, 1986 Bernardi et al, 2003), most of these hydrolytic enzymes, myrosinases, accept multiple glucosinolate substrates e.g., Chen and Halkier, (1999). However, the hydrolysis of other S- or 0-glucosides is only poorly catalysed by these enzymes (Lein, 1972 Durham and Poulton, 1990 Bernardi et al, 2003). 

Dayan, F.E., Kuhajek, J.M., Canel, G., Watson, S.B. and Moraes, R.M. (2003) Podophyllum peltatum possesses a p-glucosidase with high substrate specificity for the aryl-tetralin lignan podophyllotoxin. Biochim. Biophys. Acta, 1646,157-63. 

Vardosanidze, M., Gurielidze, K., Pruidze, G. and Paseshnichenko, V. (1991) The substrate specificity oiAlliium erubescens (3-glucosidase. Biokhymia, 56, 2025-31. 

Twenty-three strains may have possessed an a-D-glucosidase incapable of hydrolyzing sucrose, either because of (i) restricted substrate-specificity, or (it) inaccessibility of the enzyme owing to the... 

Grinna, L. S., and Robbins, P. W. (1980). Substrate specificities of rat liver microsomal glucosidases which process glycoproteins. J. Biol. Chem. 255, 2255-2258. 

Pocsi I, Kiss L, Hughes MA, Nanasi P (1989) Kinetic Investigation of the Substrate Specificity of the Cyanogenic-/J-glucosidase (Linamarase) of White Clover. Arch Biochem Biophys 272 496... 

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