Substrate specificity and diastereoselectivity of strictosidine glucosidase, a key enzyme in monoterpene indole alkaloid biosynthesis.
Strictosidine glucosidase (SGD) from Catharanthus roseus catalyzes the deglycosylation of strictosidine, an intermediate from which thousands of monoterpene indole alkaloids are derived. The steady-state kinetics of SGD with a variety of strictosidine analogs revealed the substrate preferences of this enzyme at two key positions of the strictosidine substrate. Additionally, SGD from C. roseus turns over both strictosidine and its stereoisomer vincoside, indicating that although this enzyme prefers the naturally occurring diastereomer, the enzyme is not completely diastereoselective. The implications of the substrate specificity of SGD in metabolic engineering efforts of C. roseus are highlighted.
Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
Nancy
N
Yerkes
Jia Xin
JX
Wu
Elizabeth
E
McCoy
M Carmen
MC
Galan
Shi
S
Chen
Sarah E
SE
O'Connor
D030008:Catharanthus / Q000201:enzymology*; D005959:Glucosidases / Q000737:chemistry*; D026121:Indole Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry*; D007700:Kinetics; D015394:Molecular Structure; D013237:Stereoisomerism; D013379:Substrate Specificity; D013729:Terpenes / Q000737:chemistry
D026121:Indole Alkaloids; D013729:Terpenes; D005959:Glucosidases; C456847:strictosidine glucosidase