Publications by authors named "Ken'ichirou Tamura"

A novel S-hydroxynitrile lyase (HNL) was purified from leaves of a plant, Baliospermum montanum, by ammonium sulfate fractionation and column chromatographies. Full-length cDNA and genomic DNA were cloned and sequenced. The latter contained two introns and one ORF encoding a 263-residue protein (subunit: 29.

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A hydroxynitrile lyase from leaves of Passiflora edulis (PeHNL) was purified and characterized for the first time. The enzyme is a monomer of 15kDa and 18kDa by SDS-PAGE, and gel filtration, respectively. Asymmetric synthesis of (R)-mandelonitrile from benzaldehyde and acetone cyanohydrin in a biphasic system employing the PeHNL from rinds of P.

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We established a simple HPLC method to determine the activity and stereochemistry of the chiral mandelonitrile synthesized from benzaldehyde and cyanide, and applied it to screen for hydroxynitrile lyase (HNL) activity of plant origin. A total of 163 species of plants among 74 families were examined for (R)- and (S)-HNL activities using the method. We discovered that homogenate of leaves of Baliospermum montanum shows (S)-HNL activity, while leaves and seeds from Passiflora edulis, and seeds from Eriobotrya japonica, Chaenomles sinensis, Sorbus aucuparia, Prunus mume, and Prunus persica show (R)-HNL activity.

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