Mechanistic Enzymology of Radical SAM Enzymes

• Project/Area Number: 15H03834
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Bio-related chemistry
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: Eguchi Tadashi 東京工業大学, 理学院, 教授 (60201365)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥17,160,000 (Direct Cost: ¥13,200,000、Indirect Cost: ¥3,960,000); Fiscal Year 2017: ¥4,680,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥1,080,000); Fiscal Year 2016: ¥4,680,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥1,080,000); Fiscal Year 2015: ¥7,800,000 (Direct Cost: ¥6,000,000、Indirect Cost: ¥1,800,000)
• Keywords: ラジカルSAM酵素 / 生合成 / 反応機構

Outline of Final Research Achievements

In this study, functional analysis of a radical S-adenosyl-L-methionine (SAM) dehydratase AprD4 and a methylcobalamin-dependent radical SAM methyltransferase Fom3 were performed.
A radical SAM dehydratase AprD4 and an NADPH-dependent reductase AprD3 are responsible for the C3′-deoxygenation of pseudodisaccharide paromamine in the biosynthesis of apramycin/tobramycin. AprD4 catalyzes the C3’-dehydration of paromamine via a radical-mediated reaction mechanism to give 4’-oxolividamine, which is then reduced by AprD3 with NADPH to afford lividamine. Further, the substrate specificity of this unique combination of enzymes has been investigated.
A methylcobalamin-dependent radical SAM methyltransferase Fom3 was found to catalyze the C-methylation of cytidylyl-2-hydroxyethylphosphonate to give cytidylyl-2-hydroxypropylphosphonate in the biosynthesis of a unique C-P bond containing antibiotic fosfomycin in Streptomyces.

Research Products

• [Journal Article] Methylcobalamin-Dependent Radical SAM C-Methyltransferase Fom3 Recognizes Cytidylyl-2-hydroxyethylphosphonate and Catalyzes the Nonstereoselective C-Methylation in Fosfomycin Biosynthesis (2017)
  • Author(s): Sato Shusuke、Kudo Fumitaka、Kim Seung-Young、Kuzuyama Tomohisa、Eguchi Tadashi
  • Journal Title: Biochemistry Volume: 56 Issue: 28 Pages: 3519-3522
  • DOI: 10.1021/acs.biochem.7b00472
  • Peer Reviewed
• [Journal Article] Fosfomycin Biosynthesis via Transient Cytidylylation of 2-Hydroxyethylphosphonate by the Bifunctional Fom1 Enzyme (2017)
  • Author(s): Su-Hee Cho, Seung-Young Kim, Takeo Tomita, Taro Shiraishi, Jin-Soo Park, Shusuke Sato, Fumitaka Kudo, Tadashi Eguchi, Nobutaka Funa, Makoto Nishiyama, Tomohisa Kuzuyama
  • Journal Title: ACS Chem. Biol. Volume: 12 Issue: 8 Pages: 2209-2215
  • DOI: 10.1021/acschembio.7b00419
  • Peer Reviewed
• [Journal Article] Substrate Specificity of Radical S-Adenosyl-L-methionine Dehydratase AprD4 and Its Partner Reductase AprD3 in the C3′-Deoxygenation of Aminoglycoside Antibiotics (2017)
  • Author(s): Fumitaka Kudo, Takeshi Tsunoda, Makoto Takashima, Tadashi Eguchi
  • Journal Title: J. Antibiot. Volume: 70 Issue: 4 Pages: 423-428
  • DOI: 10.1038/ja.2016.110
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Aminoglycoside Antibiotics: New Insights into the Biosynthetic Machinery of Old Drugs (2016)
  • Author(s): F. Kudo and T. Eguchi
  • Journal Title: Chem. Rec. Volume: 16 Issue: 1 Pages: 4-18
  • DOI: 10.1002/tcr.201500210
  • Peer Reviewed / Acknowledgement Compliant
• [Presentation] ホスホマイシン生合成におけるラジカルS-アデノシル-L-メチオニンC-メチル化酵素の機能解析 (2017)
  • Author(s): 佐藤 秀亮・工藤 史貴・江口 正・葛山 智久
  • Organizer: 日本化学会第97春季年会
  • Place of Presentation: 慶應義塾大学 日吉キャンパス
  • Year and Date: 2017-03-16
• [Presentation] ホスホマイシン生合成におけるC-メチル化機構 (2017)
  • Author(s): 佐藤 秀亮, Kim Seung-Young, 葛山 智久, 工藤 史貴, 江口 正
  • Organizer: 第59回天然有機化合物討論会
• [Presentation] Radical SAM Enzymes involved in Natural Product Biosynthesis (2017)
  • Author(s): Tadashi Eguchi
  • Organizer: 9th US-Japan Seminar on the Biosynthesis of Natural Products
  • Int'l Joint Research / Invited
• [Presentation] Biosynthesis of Aminoglycoside antibiotics (2015)
  • Author(s): Tadashi Eguchi
  • Organizer: PACIFICHEM 2015, International Chemical Congress of Pacific Basin Societies
  • Place of Presentation: Honolulu, Hawaii, USA
  • Year and Date: 2015-12-15
  • Int'l Joint Research / Invited
• [Presentation] Reaction mechanisms of radical SAM enzymes involved in the biosynthesis of aminoglycoside antibiotics (2015)
  • Author(s): Fumitaka Kudo, Shota Hoshi, Tadashi Eguchi
  • Organizer: PACIFICHEM 2015, International Chemical Congress of Pacific Basin Societies
  • Place of Presentation: Honolulu, Hawaii, USA
  • Year and Date: 2015-12-15
  • Int'l Joint Research
• [Remarks] 江口正研究室
  • URL: http://www.chemistry.titech.ac.jp/~eguchi/
• [Remarks] 江口正研究室 東京工業大学理学院化学系
  • URL: http://www.chem.titech.ac.jp/~eguchi/publications.html