5-HYDROXYPENTANE-2,3-DIONE (LAURENCIONE), A BACTERIAL METABOLITE OF 1-DEOXY-D-THREO-PENTULOSE

Cell-free systems from the bacteria Escherichia coli and Klebsiella pl anticola that were incubated with C-13 labeled pyruvate and D-glyceral dehyde synthesized 5-hydroxypentane-2,3-dione (laurencione) along with 1-deoxy-D-threo-pentulose (1-deoxy-D-xylulose). Both compounds showed identical labeling patterns, indicating that the C-5 skeletons were d erived from the condensation of (hydroxyethyl)thiamin on D-glyceraldeh yde. Conversion of [5,5-H-2(2)]deoxyxylutose into laurencione by a cel l-free system from E. coil showed that the alpha-dione is obtained fro m the pentulose by water elimination. (C) 1998 Published by Elsevier S cience Lid. All rights reserved.