Site-specific enzymatic hydrolysis of taxanes at C-10 and C-13

• Published in: The Journal of biological chemistry 1994-09, Vol.269 (35), p.22145-22149
• Main Authors: Hanson, R L, Wasylyk, J M, Nanduri, V B, Cazzulino, D L, Patel, R N, Szarka, L J
• Format: Article
• Language: English
• Subjects: Bridged Bicyclo Compounds - chemistry; Bridged Bicyclo Compounds - metabolism; Bridged-Ring Compounds; Carboxylic Ester Hydrolases - isolation & purification; Carboxylic Ester Hydrolases - metabolism; Chromatography, High Pressure Liquid; Electrophoresis, Polyacrylamide Gel; Hydrolysis; Nocardiaceae - enzymology; Paclitaxel - metabolism; Substrate Specificity; Taxoids
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1016/S0021-9258(17)31767-2

The production of large amounts of paclitaxel for use as an anticancer treatment has been a challenging problem because of the low concentration of the compound in yew trees and its occurrence as part of a mixture of other taxanes. Two novel enzymes were isolated to facilitate the production of 10-deacetylbaccatin III, a precursor used for semisynthesis of paclitaxel and analogs. A strain of Nocardioides albus (SC13911) was isolated from soil and found to produce an extracellular enzyme that specifically removed the C-13 side chain from paclitaxel, cephalomannine, 7-beta-xylosyltaxol, 7-beta-xylosyl-10-deacetyltaxol, and 10-deacetyltaxol. The enzyme was purified to near homogeneity to give a polypeptide with 47,000 M(r) on a sodium dodecyl sulfate gel. A strain of Nocardioides luteus (SC13912) isolated from soil was found to produce an intracellular 10-deacetylase that removed the 10-acetate from baccatin III and paclitaxel. The 10-deacetylase was purified to give a polypeptide with 40,000 M(r) on a sodium dodecyl sulfate gel. Treatment of extracts prepared from a variety of yew cultivars with the C-13-deacylase and C-10-deacetylase converted a complex mixture of taxanes primarily to 10-deacetylbaccatin III and increased the amount of this key precursor by 4-24 times.