Tetsuji Nakamura

ε-caprolactam, a new powerful inducer for the formation of Rhodococcus rhodochrous J1 nitrilase

We found that ε-caprolactam is a new powerful inducer for the formation of Rhodococcus rhodochrous J1 nitrilase. When Rhodococcus rhodochrous J1 cells were cultivated at 28°C for 120 h in a nutrient medium supplemented with 0.5% (w/v) ε-caprolactam, an enormous amount of nitrilase was formed in the cells which corresponded to approximately 30% of all soluble protein. The level of ε-caprolactam in the culture broth barely decreased in the course of cultivation. γ-Butyrolactam and δ-valerolactam also caused effective induction. The induction of nitrilase formation by ε-caprolactam was also observed in some other Rhodococcus strains.

A new catalytic function of halohydrin hydrogen-halide-lyase, synthesis of β-hydroxynitriles from epoxides and cyanide

Halohydrin hydrogen-halide-lyase, which catalyzes the interconversion of halohydrins to epoxides, purified from a recombinant E. coli was found to catalyze the transformation of 1,2-epoxybutane into beta-hydroxyvaleronitrile in the presence of cyanide. Chloride inhibited competitively the formation of beta-hydroxyvaleronitrile. The enzyme also catalyzed the transformation of some other epoxides into the corresponding beta-hydroxynitriles in the presence of cyanide.

A new enzymatic synthesis of (R)-γ-chloro-β-hydroxybutyronitrile

Abstract A new enzymatic synthesis of (R)-γ-chloro-β-hydroxybutyronitrile from epichlorohydrin or 1,3-dichloro-2-propanol using halohydrin hydrogen-halide-lyase purified from a recombinant Escherichia coli that carried the enzyme gene of Corynebacterium sp. strain N-1074 was described.

Purification and characterization of halohydrin hydrogen-halide lyase from a recombinant Escherichia coli containing the gene from a Corynebacterium sp

SummaryAn enzyme catalyzing the interconversion of 1,3-dichloro-2-propanol (DCP) to epichlorohydrin (ECH) was purified from Escherichia coli JM109/ pST001, which carried the gene from Corynebacterium sp. N-1074. The enzyme was crystallized by the addition of ammonium sulphate. The enzyme had a relative molecular mass (Mr) of about 105 000 and consisted of four subunits identical in Mr (approx. 28 000). The enzyme catalysed both the transformation of various halohydrins into the corresponding epoxides with liberation of halide and its reverse reaction. These facts indicated that the enzyme was halohydrin hydrogen-halidelyase.