Biosynthesis of terpenoids: 1-deoxy-D-xylulose-5-phosphate reductoisomerase from Escherichia coli is a class B dehydrogenase.
1-Deoxy-D-xylulose-5-phosphate is converted into 2-C-methyl-D-erythritol-4-phosphate by the catalytic action of 1-deoxy-D-xylulose-5-phosphate reductoisomerase (Dxr protein) using NADPH as cofactor. The stereochemical features of this reaction were investigated in in vitro experiments with the recombinant Dxr protein of Escherichia coli using (4R)- or (4S)-[4-(2)H(1)]NADPH as coenzyme. The enzymatically formed 2-C-methyl-D-erythritol-4-phosphate was isolated and converted into 1,2:3,4-di-O-isopropylidene-2-C-methyl-D-erythritol; NMR spectroscopic investigation of this derivative indicated that only (4S)-[4-(2)H(1)]NADPH affords 2-C-methyl-D-erythritol-4-phosphate labelled exclusively in the H(Re) position of C-1. Stereospecific transfer of H(Si) from C-4 of the cofactor identifies the Dxr protein of E. coli as a class B dehydrogenase.
Radykewicz
T
T
Lehrstuhl für Organische Chemie und Biochemie, Technische Universität München, Lichtenbergstr. 4, D-85747, Garching, Germany.
Rohdich
F
F
Wungsintaweekul
J
J
Herz
S
S
Kis
K
K
Eisenreich
W
W
Bacher
A
A
Zenk
M H
MH
Arigoni
D
D
D019747:Aldose-Ketose Isomerases / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology*; D009682:Magnetic Resonance Spectroscopy; D009097:Multienzyme Complexes / Q000378:metabolism*; D010088:Oxidoreductases / Q000378:metabolism*; D013729:Terpenes / Q000378:metabolism*
D009097:Multienzyme Complexes; D013729:Terpenes; D010088:Oxidoreductases; C114231:1-deoxy-D-xylulose 5-phosphate reductoisomerase; D019747:Aldose-Ketose Isomerases