title: Characterization of two acyl-acyl carrier protein thioesterases from developing Cuphea seeds specific for medium-chain- and oleoyl-acyl carrier protein.
abstract: Two acyl-acyl carrier protein (ACP) thioesterases were partially purified from developing seeds of Cuphea lanceolata Ait., a plant with decanoic acid-rich triacylglycerols. The two enzymes differ markedly in their substrate specificity. One is specific for medium-chain acyl-ACPs, the other one for oleoyl-ACP. In addition, these enzymes are distinct with regard to molecular weight, pH optimum and sensitivity to salt. The thioesterases could be separated by Mono Q chromatography or gel filtration. The medium-chain acyl-ACP thioesterase and oleoyl-ACP thioesterase were purified from a crude extract 29- and 180-fold, respectively. In Cuphea wrightii A. Gray, which predominantly contains decanoic a nd lauric acid in the seeds, two different thioesterases were also found with a similar substrate specificity as in Cuphea lanceolata.
authors.affiliation: Department of Botany and Plant Pathology, Michigan State University, 48824-1312, East Lansing, MI, USA.
authors.forename: P
authors.initials: P
authors.lastname: Dörmann
authors.forename: F
authors.initials: F
authors.lastname: Spener
authors.forename: J B
authors.initials: JB
authors.lastname: Ohlrogge