Profiling a Taxol pathway 10beta-acetyltransferase: assessment of the specificity and the production of baccatin III by in vivo acetylation in E. coli.
The 10beta-acetyltransferase on the biosynthetic pathway of the antineoplastic drug Taxol catalyzes the regiospecific transfer of the acetyl group of acetyl-coenzyme A (CoA) to 10-deacetylbaccatin III. We demonstrate that in addition to acetyl group transfer, the overexpressed enzyme also catalyzes the exchange of propionyl and n-butyryl from the corresponding CoA thioester to the hydroxyl group at C10 of the cosubstrate. Also, in vivo studies revealed that E. coli, producing endogenous acetyl-CoA and overexpressing the recombinant acetyltransferase, can convert exogenously supplied 10-deacetylbaccatin III to baccatin III. Potentially, this heterologous in vivo production method in bacteria could be optimized to couple various unnatural acyl-CoA analogs to myriad amino and/or hydroxyl acceptors by acyltransferase catalysis; conceivably, this process could facilitate the preparation of second-generation Taxols.
Loncaric
Catherine
C
Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA.
Merriweather
Erin
E
Walker
Kevin D
KD
D000105:Acetyl Coenzyme A / Q000378:metabolism; D000107:Acetylation; D000123:Acetyltransferases / Q000378:metabolism*; D000470:Alkaloids / Q000096:biosynthesis*; D000972:Antineoplastic Agents, Phytogenic / Q000096:biosynthesis; D002384:Catalysis; D002851:Chromatography, High Pressure Liquid; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D008956:Models, Chemical; D017239:Paclitaxel / Q000096:biosynthesis; D013379:Substrate Specificity; D043823:Taxoids / Q000378:metabolism*; D013997:Time Factors
D000470:Alkaloids; D000972:Antineoplastic Agents, Phytogenic; D043823:Taxoids; C073950:baccatin III; C042213:10-deacetylbaccatine III; D000105:Acetyl Coenzyme A; D000123:Acetyltransferases; D017239:Paclitaxel