Publications by authors named "Tomoyuki Nishi"

Modification of the genetic background and, in some cases, the introduction of targeted mutations can play a critical role in producing trait characteristics during the breeding of crops, livestock, and microorganisms. However, the question of how similar trait characteristics emerge when the same target mutation is introduced into different genetic backgrounds is unclear. In a previous study, we performed genome editing of , , , and on the standard sake yeast strain Kyokai No.

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Terpene synthase (TS) from Bacillus alcalophilus (BalTS) is the only Class IB TS for which a 3D structure has been elucidated. Recently, geranyl-β-phellandrene, a novel cyclic diterpene, was identified as a product of BalTS in addition to the acyclic β-springene. In the present study, we have provided insight into the mechanism of geranyl-β-phellandrene formation.

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Sake yeast is mostly diploid, so the introduction of recessive mutations to improve brewing characteristics requires considerable effort. To construct sake yeast with multiple excellent brewing characteristics, we used an evidence-based approach that exploits genome editing technology. Our breeding targeted the , , , and genes.

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Terpene synthases (TS) are classified into two broad types, Class I and II, based on the chemical strategy for initial carbocation formation and motif sequences of the catalytic site. We have recently identified a new class of enzymes, Class IB, showing the acceptability of long (C-C) prenyl-diphosphates as substrates and no amino acid sequence homology with known TS. Conversion of long prenyl-diphosphates such as heptaprenyl-diphosphate (C) is unusual and has never been reported for Class I and II enzymes.

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produces daurichromenic acid, an anti-HIV meroterpenoid, via oxidative cyclization of the farnesyl group of grifolic acid. The prenyltransferase (PT) that synthesizes grifolic acid is a farnesyltransferase in plant specialized metabolism. In this study, we demonstrated that the isoprenoid moiety of grifolic acid is derived from the 2--methyl-d-erythritol-4-phosphate pathway that takes place in plastids.

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Thousands of terpenes have been identified to date. However, only two classes of enzymes are known to be involved in their biosynthesis, and each class has characteristic amino-acid motifs. We recently identified a novel large-terpene (C/C/C) synthase, which shares no motifs with known enzymes.

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