Kohji Yamamoto

Summary

Affiliation: Kyushu University
Country: Japan

Publications

  1. Yamamoto K, Higashiura A, Hirowatari A, Yamada N, Tsubota T, Sezutsu H, et al. Characterisation of a diazinon-metabolising glutathione S-transferase in the silkworm Bombyx mori by X-ray crystallography and genome editing analysis. Sci Rep. 2018;8:16835 pubmed publisher
    ..Thus, this study provides insights into the physiological role of bmGSTu2 in silkworms, detoxification of organophosphate insecticides, and drug targets for the development of a novel insecticide. ..
  2. Yamamoto K, Higashiura A, Suzuki M, Aritake K, Urade Y, Uodome N, et al. Crystal structure of a Bombyx mori sigma-class glutathione transferase exhibiting prostaglandin E synthase activity. Biochim Biophys Acta. 2013;1830:3711-8 pubmed publisher
    ..We determined the tertiary structure of bmGSTS1 exhibiting prostaglandin E synthase activity. These results are, to our knowledge, the first report of a prostaglandin synthase activity in insects. ..
  3. Yamamoto K, Higashiura A, Hossain M, Yamada N, Shiotsuki T, Nakagawa A. Structural characterization of the catalytic site of a Nilaparvata lugens delta-class glutathione transferase. Arch Biochem Biophys. 2015;566:36-42 pubmed publisher
    ..Site-directed mutagenesis of nlGSTD mutants indicated that amino acid residues Ser11, His52, Glu66, and Phe119 contribute to catalytic activity. ..
  4. Yamamoto K, Banno Y, Fujii H, Miake F, Kashige N, Aso Y. Catalase from the silkworm, Bombyx mori: gene sequence, distribution, and overexpression. Insect Biochem Mol Biol. 2005;35:277-83 pubmed
    ..The Michaelis constant for hydrogen peroxide was evaluated to be 28 mM at pH 6.5 and 30 degrees C. rCAT was suggested to be a member of the typical catalase family. ..
  5. Yamamoto K, Suzuki M, Higashiura A, Nakagawa A. Three-dimensional structure of a Bombyx mori Omega-class glutathione transferase. Biochem Biophys Res Commun. 2013;438:588-93 pubmed publisher
    ..Site-directed mutagenesis of bmGSTO mutants indicated that amino acid residues Leu62, Lys65, Lys77, Val78, Glu91 and Ser92 in the G-site contribute to catalytic activity. ..
  6. Yamamoto K, Higashiura A, Suzuki M, Shiotsuki T, Sugahara R, Fujii T, et al. Structural characterization of an aldo-keto reductase (AKR2E5) from the silkworm Bombyx mori. Biochem Biophys Res Commun. 2016;474:104-110 pubmed publisher
    ..To the best of our knowledge, AKR2E5 is only the second AKR characterized in silkworm. Our data should contribute to further understanding of the functional activity of insect AKRs. ..
  7. Yamamoto K, Wilson D. Identification, characterization, and crystal structure of an aldo-keto reductase (AKR2E4) from the silkworm Bombyx mori. Arch Biochem Biophys. 2013;538:156-63 pubmed publisher
    ..This structure constitutes the first insect AKR structure determined. Bound NADPH is located at the center of the TIM- or (?/?)8-barrel, and residues involved in catalysis are conserved. ..
  8. Yamamoto K, Suzuki M, Higashiura A, Aritake K, Urade Y, Uodome N, et al. New insights into the catalytic mechanism of Bombyx mori prostaglandin E synthase gained from structure-function analysis. Biochem Biophys Res Commun. 2013;440:762-7 pubmed publisher
    ..These results are, to our knowledge, the first to reveal the presence of an electron-sharing network in bmPGES. ..
  9. Yamamoto K, Ichinose H, Aso Y, Banno Y, Kimura M, Nakashima T. Molecular characterization of an insecticide-induced novel glutathione transferase in silkworm. Biochim Biophys Acta. 2011;1810:420-6 pubmed publisher
    ..Kinetic analysis of bmGSTu mutants indicated that Tyr7, Ser12 and Asn50 are involved in enzyme function. These results support the hypothesis that bmGSTu may play a role in insecticide resistance in Bombyx mori. ..

More Information

Publications17

  1. Yamamoto K, Usuda K, Kakuta Y, Kimura M, Higashiura A, Nakagawa A, et al. Structural basis for catalytic activity of a silkworm Delta-class glutathione transferase. Biochim Biophys Acta. 2012;1820:1469-74 pubmed publisher
    ..Kinetic analysis of bmGSTD mutants indicated that Ser11, Gln51, His52, Ser67, and Arg68 are important for enzyme function. These results provide structural insights into the catalysis of glutathione conjugation in B. mori by bmGSTD. ..
  2. Yamamoto K, Zhang P, Miake F, Kashige N, Aso Y, Banno Y, et al. Cloning, expression and characterization of theta-class glutathione S-transferase from the silkworm, Bombyx mori. Comp Biochem Physiol B Biochem Mol Biol. 2005;141:340-6 pubmed
    ..Incubation for 30 min at temperatures below 50 degrees C also affected the activity insignificantly. The Michaelis constant for 1-chloro-2,4-dinitrobenzene was 0.48 mM. ..
  3. Yamamoto K, Fujii H, Aso Y, Banno Y, Koga K. Expression and characterization of a sigma-class glutathione S-transferase of the fall webworm, Hyphantria cunea. Biosci Biotechnol Biochem. 2007;71:553-60 pubmed
    ..We also found that as compared to B. mori Sigma-class GST, rhcGST had a higher affinity for fenitrothion, an organophosphorus insecticide. ..
  4. Yamamoto K, Nagaoka S, Banno Y, Aso Y. Biochemical properties of an omega-class glutathione S-transferase of the silkmoth, Bombyx mori. Comp Biochem Physiol C Toxicol Pharmacol. 2009;149:461-7 pubmed publisher
    ..These results indicate that bmGSTO could be involved in the increase in level of insecticide resistance for lepidopteran insects. ..
  5. Yamamoto K, Teshiba S, Shigeoka Y, Aso Y, Banno Y, Fujiki T, et al. Characterization of an omega-class glutathione S-transferase in the stress response of the silkmoth. Insect Mol Biol. 2011;20:379-86 pubmed publisher
    ..Thus, bmGSTO could contribute to increasing the environmental stress resistance of lepidopteran insects...
  6. Yamamoto K, Aso Y, Yamada N. Catalytic function of an ?-class glutathione S-transferase of the silkworm. Insect Mol Biol. 2013;22:523-31 pubmed publisher
    ..These residues were replaced with alanine by site-directed mutagenesis and subsequent kinetic analysis of bmGSTE mutants indicated that His53, Val55, and Ser68 were important for enzyme function. ..
  7. Yamamoto K, Higashiura A, Suzuki M, Aritake K, Urade Y, Nakagawa A. Molecular structure of a prostaglandin D synthase requiring glutathione from the brown planthopper, Nilaparvata lugens. Biochem Biophys Res Commun. 2017;492:166-171 pubmed publisher
    ..Our findings provide insights into the mechanism of nlPGDS activity and potentially that of other insects and therefore may facilitate the development of more effective and safe insecticides. ..
  8. Yamamoto K, Zhang P, Banno Y, Fujii H, Miake F, Kashige N, et al. Superoxide dismutase from the silkworm, Bombyx mori: sequence, distribution, and overexpression. Biosci Biotechnol Biochem. 2005;69:507-14 pubmed publisher
    ..bmSOD at 4 degrees C retained almost all of its original activity after incubation at pH 4-11 for 24 h. Incubation (pH 7) for 30 min at temperatures below 40 degrees C also affected activity insignificantly...