Yamamoto K, Oishi K, Fujimatsu I, Komatsu K
Pharmaceutical Research and Development Department, Asahi Chemical Industry Company Ltd., Miyazaki, Japan.
Appl Environ Microbiol. 1991 Oct;57(10):3028-32. doi: 10.1128/aem.57.10.3028-3032.1991.
R-(-)-Mandelic acid was produced from racemic mandelonitrile by Alcaligenes faecalis ATCC 8750. Ammonium acetate or L-glutamic acid as the carbon source and n-butyronitrile as the inducer in the culture medium were effective for bacterial growth and the induction of R-(-)-mandelic acid-producing activity. The R-(-)-mandelic acid formed from mandelonitrile by resting cells was present in a 100% enantiomeric excess. A. faecalis ATCC 8750 has an R-enantioselective nitrilase for mandelonitrile and an amidase for mandelamide. As R-(-)-mandelic acid was produced from racemic mandelonitrile in a yield of 91%, whereas no S-mandelonitrile was left, the S-mandelonitrile remaining in the reaction is spontaneously racemized because of the chemical equilibrium and is used as the substrate. Consequently, almost all the mandelonitrile is consumed and converted to R-(-)-mandelic acid. R-(-)-Mandelic acid was also produced when benzaldehyde plus HCN was used as the substrate.
粪产碱菌ATCC 8750可由外消旋扁桃腈生产R-(-)-扁桃酸。培养基中以乙酸铵或L-谷氨酸作为碳源，正丁腈作为诱导剂，对细菌生长和R-(-)-扁桃酸生产活性的诱导有效。由静息细胞将扁桃腈转化形成的R-(-)-扁桃酸对映体过量百分数为100%。粪产碱菌ATCC 8750具有对扁桃腈的R-对映选择性腈水解酶和对扁桃酰胺的酰胺酶。由于外消旋扁桃腈生成R-(-)-扁桃酸的产率为91%，且没有剩余S-扁桃腈，反应中剩余的S-扁桃腈因化学平衡而自发外消旋，并用作底物。因此，几乎所有的扁桃腈都被消耗并转化为R-(-)-扁桃酸。当使用苯甲醛加HCN作为底物时，也能产生R-(-)-扁桃酸。
