KEIO RESEARCHERS INFORMATION SYSTEM

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Profile Summary 【 Display / hide 】

• 我々のミッションは「合成生物学を使い、ケミストリーではできないモノづくりを」です。
  
  20世紀の100年間、ケミストリーを使ったモノづくりは多くの問題を解決し、人間社会を豊かにしました。化学肥料、プラスチック、医薬品など、人間の生活には欠かせない様々な製品がケミストリーの力によって生み出されました。
  
  そして現在、人類は新たな多くの問題に直面しています。気候変動、ウイルス・細菌の蔓延、病気、等の重大な問題に対峙していかなければならず、ケミストリーのみに頼るモノづくりには限界があります。
  
  湯澤研究室はケミストリーではできないモノづくりを合成生物学のアプローチで行います。人工的に設計した巨大酵素および微生物によって、分子量数百から数千の多種多様な化合物を生産し、上記の重大な問題に対峙していきます。

Books 【 Display / hide 】

Books 【 Display / hide 】

• バイオエネルギー再燃

  植田, 充美, シーエムシー出版, 2021.11,  Page： vi, 289p

• Comprehensive Natural Products III

  Hung-Wen (Ben) Liu and Tadhg P. Begley, Elsevier, 2020

Papers 【 Display / hide 】

Papers 【 Display / hide 】

• Complete Genome Sequence of Streptomyces albus Strain G153

  Takeda T., Fukumitsu N., Yuzawa S., Arakawa K.

  Microbiology Resource Announcements (Microbiology Resource Announcements)  11 ( 7 )  2022.07

  　View Summary

  The genus Streptomyces is a promising source of biologically active secondary metabolites. Here, we report the complete genome sequence of Streptomyces albus strain G153. The assembled genome comprised a single linear chromosome of 6.9 Mbp with a G1C content of 73.3%.

  • Access to Document (DOI)

• Reconstitution of a Highly Reducing Type II PKS System Reveals 6pi-Electrocyclization Is Required for o-Dialkylbenzene Biosynthesis

  Zhang, J., Yuzawa, S., Thong, W. L., Shinada, T., Nishiyama, M. and Kuzuyama, T.

  J Am Chem Soc 143 ( 7 ) 2962 - 2969 2021.02

  ISSN  1520-5126

  　View Summary

  Natural products containing an o-dialkylbenzene moiety exhibit a wide variety of bioactivities, including antibacterial, antifungal, antitumor, and antiangiogenic activities. However, the biosynthetic scheme of the o-dialkylbenzene moiety remains unclear. In this study, we identified the biosynthetic gene cluster (BGC) of compounds 1 and 2 in Streptomyces sp. SANK 60404, which contains a rare o-dialkylbenzene moiety, and successfully reconstituted the biosynthesis of 1 using 22 recombinant enzymes in vitro. Our study established a biosynthetic route for the o-tolyl group within the o-dialkylbenzene moiety, where the triene intermediate 3 loaded onto a unique acyl carrier protein (ACP) is elongated by a specific ketosynthase-chain length factor pair of a type II polyketide synthase system with the aid of a putative isomerase to be termed "electrocyclase" and a thioesterase-like enzyme in the BGC. The C2-elongated all-trans diketo-triene intermediate is subsequently isomerized to the 6Z configuration by the electrocyclase to allow intramolecular 6pi-electrocyclization, followed by coenzyme FAD/FMN-dependent dehydrogenation. Bioinformatics analysis showed that the key genes are all conserved in BGCs of natural products containing an o-dialkylbenzene moiety, suggesting that the proposed biosynthetic scheme is a common strategy to form o-dialkylbenzenes in nature.

  • Access to Document (DOI)

• A Reporter System for Cytosolic Protein Aggregates in Yeast.

  David Romero-Suarez, Tune Wulff, Yixin Rong, Tadas Jakočiu Nas, Satoshi Yuzawa, Jay D Keasling, Michael K Jensen

  ACS synthetic biology  2021.02

  Accepted

  　View Summary

  Protein misfolding and aggregation are linked to neurodegenerative diseases of mammals and suboptimal protein expression within biotechnology. Tools for monitoring protein aggregates are therefore useful for studying disease-related aggregation and for improving soluble protein expression in heterologous hosts for biotechnology purposes. In this work, we developed a promoter-reporter system for aggregated protein on the basis of the yeast native response to misfolded protein. To this end, we first studied the proteome of yeast in response to the expression of folded soluble and aggregation-prone protein baits and identified genes encoding proteins related to protein folding and the response to heat stress as well as the ubiquitin-proteasome system that are over-represented in cells expressing an aggregation-prone protein. From these data, we created and validated promoter-reporter constructs and further engineered the best performing promoters by increasing the copy number of upstream activating sequences and optimization of culture conditions. Our best promoter-reporter has an output dynamic range of approximately 12-fold upon expression of the aggregation-prone protein and responded to increasing levels of aggregated protein. Finally, we demonstrate that the system can discriminate between yeast cells expressing different prion precursor proteins and select the cells expressing folded soluble protein from mixed populations. Our reporter system is thus a simple tool for diagnosing protein aggregates in living cells and should be applicable for the health and biotechnology industries.

  • Access to Document (DOI)

• Short-chain ketone production by engineered polyketide synthases in Streptomyces albus

  Yuzawa, S., Mirsiaghi, M., Jocic, R., Fujii, T., Masson, F., Benites, V. T., Baidoo, E. E. K., Sundstrom, E., Tanjore, D., Pray, T. R., George, A., Davis, R. W., Gladden, J. M., Simmons, B. A., Katz, L. and Keasling, J. D.

  Nat Commun 9 ( 1 ) 4569 2018.11

  ISSN  2041-1723

  　View Summary

  Microbial production of fuels and commodity chemicals has been performed primarily using natural or slightly modified enzymes, which inherently limits the types of molecules that can be produced. Type I modular polyketide synthases (PKSs) are multi-domain enzymes that can produce unique and diverse molecular structures by combining particular types of catalytic domains in a specific order. This catalytic mechanism offers a wealth of engineering opportunities. Here we report engineered microbes that produce various short-chain (C5-C7) ketones using hybrid PKSs. Introduction of the genes into the chromosome of Streptomyces albus enables it to produce >1 g . l(-1) of C6 and C7 ethyl ketones and several hundred mg . l(-1) of C5 and C6 methyl ketones from plant biomass hydrolysates. Engine tests indicate these short-chain ketones can be added to gasoline as oxygenates to increase the octane of gasoline. Together, it demonstrates the efficient and renewable microbial production of biogasolines by hybrid enzymes.

  • Access to Document (DOI)

• Probing the Flexibility of an Iterative Modular Polyketide Synthase with Non-Native Substrates in Vitro

  Curran, S. C., Hagen, A., Poust, S., Chan, L. J. G., Garabedian, B. M., de Rond, T., Baluyot, M. J., Vu, J. T., Lau, A. K., Yuzawa, S., Petzold, C. J., Katz, L. and Keasling, J. D.

  ACS Chem Biol 13 ( 8 ) 2261 - 2268 2018.08

  ISSN  1554-8937

  　View Summary

  In the search for molecular machinery for custom biosynthesis of valuable compounds, the modular type I polyketide synthases (PKSs) offer great potential. In this study, we investigate the flexibility of BorM5, the iterative fifth module of the borrelidin synthase, with a panel of non-native priming substrates in vitro. BorM5 differentially extends various aliphatic and substituted substrates. Depending on substrate size and substitution BorM5 can exceed the three iterations it natively performs. To probe the effect of methyl branching on chain length regulation, we engineered a BorM5 variant capable of incorporating methylmalonyl- and malonyl-CoA into its intermediates. Intermediate methylation did not affect overall chain length, indicating that the enzyme does not to count methyl branches to specify the number of iterations. In addition to providing regulatory insight about BorM5, we produced dozens of novel methylated intermediates that might be used for production of various hydrocarbons or pharmaceuticals. These findings enable rational engineering and recombination of BorM5 and inform the study of other iterative modules.

  • Access to Document (DOI)

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Papers, etc., Registered in KOARA 【 Display / hide 】

Papers, etc., Registered in KOARA 【 Display / hide 】

• Structural analysis of a modular polyketide synthase module

  Yuzawa, Satoshi

  科学研究費補助金研究成果報告書 2020

Reviews, Commentaries, etc. 【 Display / hide 】

Reviews, Commentaries, etc. 【 Display / hide 】

• ガソリンの微生物生産に向けた合成生物学的アプローチ

  湯澤 賢

  バイオサイエンスとインダストリー (バイオインダストリー協会)  77 ( 6 ) 440 - 443 2019

  ISSN  0914-8981

• Interview (2)(就職支援OG・OBインタビュー編,バイオ系のキャリアデザイン)

  湯澤 賢

  生物工学会誌 : seibutsu-kogaku kaishi (日本生物工学会)  93 ( 12 ) 767 - 768 2015

  ISSN  0919-3758

• 研究コミュニティーとつながる連載 研コミュ白書(第5回)スタンフォードLSJ(Life Science in Japanese) : アメリカ西海岸の日本人研究者コミュニティー

  藤島 皓介, 湯澤 賢

  細胞工学 (学研メディカル秀潤社 ; 1982-)  32 ( 3 ) 344 - 349 2013

  ISSN  0287-3796

Research Projects of Competitive Funds, etc. 【 Display / hide 】

Research Projects of Competitive Funds, etc. 【 Display / hide 】

• 合成生物学的手法による液体燃料の自在合成基盤の確立

  2022.04

  -

  2024.03

  公益財団法人・発酵研究所, 一般研究助成, Research grant, Principal investigator

• 合成生物学的手法による抗生物質の自在合成基盤の確立

  2021.04

  -

  2024.03

  文部科学省・科学技術振興機構, 創発的研究支援事業（フェーズ１）, No Setting, Principal investigator

• 非大腸菌タンパク質生産系を併用したモジュラーポリケチド合成酵素の試験管内再構成

  2021.04

  -

  2024.03

  MEXT,JSPS, Grant-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (C), Principal investigator

• ポリケチド合成酵素の動的構造と機能相関の解明

  2019.08

  -

  2021.03

  MEXT,JSPS, Grant-in-Aid for Scientific Research, Grant-in-Aid for Research Activity Start-up , Principal investigator

Courses Taught 【 Display / hide 】

Courses Taught 【 Display / hide 】

• GENETIC ANALYSIS LABORATORY

  2024

• GENETIC ANALYSIS LABORATORY

  2023

• GENETIC ANALYSIS LABORATORY

  2022