Anomalous Enhancing Effect of NH•••S Hydrogen Bonding on the Catalytic Activity of Heme Coordinated by Thiolate

• Suzuki Hiroshi

  Graduate School of Pharmaceutical Sciences, Nagoya City University

• Yamane Takehiro

  Graduate School of Pharmaceutical Sciences, Nagoya City University

• Umezawa Naoki

  Graduate School of Pharmaceutical Sciences, Nagoya City University

• Kato Nobuki

  Graduate School of Pharmaceutical Sciences, Nagoya City University

• Higuchi Tsunehiko

  Graduate School of Pharmaceutical Sciences, Nagoya City University

Bibliographic Information

Other Title

• チオレート配位ヘム錯体の触媒活性に及ぼすNH・・・S水素結合の特異な効果

Abstract

Cytochrome P450 and NO synthase have strong oxidizing ability and unusual structure, in that their heme irons have thiolate coordination. Recently, the presence of an NH···S hydrogen bond in the active site of P450 and NOS has been confirmed. We have succeeded in the synthesis of the first synthetic heme thiolate (SR complex) which retains thiolate coordination during catalytic oxidation, and also have prepared heme thiolate having NH···S hydrogen bond (SR-HB complex). We have found that catalytic oxidizing activity of SR-HB is considerably higher than that of SR complex. We have also found that redox potential (Fe(III)/Fe(IV)) of SR-HB is lower than that of SR, contrary to expectation. This finding would involve function of NH···S hydrogen bond as a positive modulator of P450 catalysis.

Journal

• Proceedings of the Symposium on Progress in Organic Reactions and Syntheses

  Proceedings of the Symposium on Progress in Organic Reactions and Syntheses 35 (0), 27-27, 2009

  Division of Organic Chemistry, The Pharmaceutical Society of Japan

Keywords

• cytochrome P450
• hydrogen bonding
• thiolate ligand
• iron porphyrin
• enzyme model

Details

• CRID: 1390001205635787776
• NII Article ID: 130006998350
• DOI: 10.14895/hannou.35.0.27.0
• Text Lang: ja
• Data Source:
  • JaLC
  • CiNii Articles
• Abstract License Flag: Disallowed