W. Eisenreich et al., STUDIES ON THE BIOSYNTHESIS OF TAXOL - THE TAXANE CARBON SKELETON IS NOT OF MEVALONOID ORIGIN, Proceedings of the National Academy of Sciences of the United Statesof America, 93(13), 1996, pp. 6431-6436
A cell culture of Taxus chinensis was established to produce the diter
pene 2 alpha,5 alpha,10 beta,14 beta-tetra-acetoxy-4(20),11-taxadiene
(taxuyunnanine C) in 2.6% (dry weight) yield. The incorporation of [U-
C-13(6)]glucose, [1-C-13]glucose, and [1,2-C-13(2)]acetate into this d
iterpene was analyzed by NMR spectroscopy, Label from [1,2-C-13(2)]ace
tate was diverted to the four acetyl groups of taxuyunnanine C, but no
t to the taxane ring system, Label from [1-C-13]glucose and [U-C-13(6)
]glucose was efficiently incorporated into both the taxane ring system
and the acetyl groups, The four isoprenoid moieties of the diterpene
showed identical labeling patterns. The analysis of long-range C-13 C-
13 couplings in taxuyunnanine C obtained from an experiment with [U-C-
13(6)]glucose documents the involvement of an intramolecular rearrange
ment in the biosynthesis of the isoprenoid precursor, The labeling pat
terns are inconsistent with the mevalonate pathway, The taxoid data sh
are important features with the alternative pathway of isoprenoid bios
ynthesis operating in certain eubacteria [Rohmer, M., Knani, M., Simon
in, P., Sutter, B. & Sahm, H. (1993) Biochem. J. 295, 517-524].