title: Enzymatic synthesis of L-[4-13C]aspartic acid.
abstract: An efficient procedure for the production of l-[4-13C]aspartic acid (4-13C-Asp) was investigated. In this procedure, phosphoenolpyruvate carboxylase originating from the methanol-assimilating microbe, Methylobacterium extorquens JCM 2805, was used for the production of labeled oxaloacetic acid from phosphoenolpyruvate (PEP) and NaH13CO3; the oxaloacetic acid was then converted to 4-13C-Asp with glutamic-oxaloacetic transaminase. In this reaction, with starting concentrations of 10 mM PEP, 10 mM NaH13CO3 and 15 mM L-glutamic acid (Glu), the yield was 70%. 4-13C-Asp and Glu in the final reaction mixture were separated by displacement chromatography. The yield of this process was 84%. The overall yield was 59%. The incorporation of 13C at the C-4 position of 4-13C-Asp was confirmed by NMR spectroscopy.
authors.affiliation: Department of Bioengineering, Faculty of Engineering, Soka University, 1-236 Tangi, Hachioji, Tokyo 192-8577, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Maeda
authors.forename: S
authors.initials: S
authors.lastname: Suzuki
authors.forename: M
authors.initials: M
authors.lastname: Ikeguchi
authors.forename: T
authors.initials: T
authors.lastname: Sakai
authors.forename: K
authors.initials: K
authors.lastname: Shibata