title: Site-specific enzymatic hydrolysis of taxanes at C-10 and C-13.
abstract: 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.
authors.affiliation: Department of Microbial Technology, Bristol-Myers Squibb Pharmaceutical Research Institute, New Brunswick, New Jersey 08903.
authors.forename: R L
authors.initials: RL
authors.lastname: Hanson
authors.forename: J M
authors.initials: JM
authors.lastname: Wasylyk
authors.forename: V B
authors.initials: VB
authors.lastname: Nanduri
authors.forename: D L
authors.initials: DL
authors.lastname: Cazzulino
authors.forename: R N
authors.initials: RN
authors.lastname: Patel
authors.forename: L J
authors.initials: LJ
authors.lastname: Szarka
mesh_terms: D001643:Bridged Bicyclo Compounds / Q000737:chemistry / Q000378:metabolism; D001952:Bridged-Ring Compounds; D002265:Carboxylic Ester Hydrolases / Q000302:isolation & purification / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D006868:Hydrolysis; D009618:Nocardiaceae / Q000201:enzymology; D017239:Paclitaxel / Q000378:metabolism*; D013379:Substrate Specificity; D043823:Taxoids
chemical_list: D001643:Bridged Bicyclo Compounds; D001952:Bridged-Ring Compounds; D043823:Taxoids; C080625:taxane; C089124:C-10-deacetylase; C089123:C-13-deacylase; D002265:Carboxylic Ester Hydrolases; D017239:Paclitaxel