MSGID: 1:317/3 6270b02b   
   PID: hpt/lnx 1.9.0-cur 2019-01-08   
   TID: hpt/lnx 1.9.0-cur 2019-01-08   
    Researchers develop powerful strategy for creating new-to-nature enzymes   
      
      
     Date:   
         May 2, 2022   
     Source:   
         University of Illinois at Urbana-Champaign Institute for   
         Sustainability, Energy, and Environment   
     Summary:   
         Scientists achieve a novel biocatalytic reaction by repurposing   
         natural enzymes with light, which could lead to valuable new   
         chemical compounds.   
      
      
      
   FULL STORY   
   ==========================================================================   
   Engineering enzymes to perform reactions not found in nature can address   
   longstanding challenges in the world of synthetic chemistry, such as   
   upgrading plant-based oils into useful biochemicals.   
      
      
   ==========================================================================   
   A team of researchers has developed a simple yet powerful strategy for   
   creating new enzymes with novel reactivity that can produce valuable   
   chemical compounds, building on their previous work using light to   
   repurpose naturally occurring enzymes.   
      
   The study, published in Nature Catalysis, was led by Xiaoqiang   
   Huang, a former postdoctoral researcher in the University of Illinois   
   Urbana-Champaign's Department of Chemical and Biomolecular Engineering   
   (ChBE) and the Center for Advanced Bioenergy and Bioproducts Innovation   
   (CABBI), a U.S. Department of Energy-funded Bioenergy Research   
   Center. Huang, currently an Assistant Professor at the Nanjing University   
   in China, carried out this work in the laboratory of ChBE Professor   
   Huimin Zhao, CABBI's Conversion Theme Leader and an affiliate of the   
   Carl R. Woese Institute for Genomic Biology (IGB).   
      
   In the study, visible light was used to excite an engineered ketoreductase   
   enzyme, enabling a new-to-nature biocatalytic reaction known as an   
   asymmetric radical conjugate addition, which is extremely difficult to   
   achieve by chemical catalysis.   
      
   Catalysts are substances used to speed up chemical reactions. In living   
   organisms, protein molecules called enzymes catalyze reactions in a   
   process called biocatalysis. Scientists have begun using biocatalysis   
   to synthesize valuable compounds, as its high selectivity allows them   
   to deploy enzymes to act on specific substrates and create target   
   products. Another advantage is that enzymatic reactions are highly   
   sustainable. They are relatively inexpensive, consume low levels of   
   energy, and do minimal damage to the environment -- as opposed to   
   chemical catalysts, which typically require organic solvents, heat,   
   and high pressure to function.   
      
   Still, enzymes are complicated to work with. They are normally limited to   
   catalyzing reactions found in nature, meaning scientists often struggle   
   to track down the perfect biocatalyst to meet their needs. Zhao's lab   
   has focused on steering biocatalysis with visible light, a process known   
   as "photobiocatalysis," to produce new enzyme reactivity. In a previous   
   study, Zhao and Huang developed a visible light-induced reaction using an   
   enzyme named ene-reductase (ER) as a biocatalyst to produce high yields   
   of valuable chiral carbonyl compounds, which have potential applications   
   for production of high value chemicals.   
      
   The new study builds on that work, using photobiocatalysis on a different   
   enzyme family -- nicotamide-dependent ketoreductases produced by bacteria   
   - - and a different chemical mechanism to produce another type of chiral   
   carbonyl compounds known as a-chiral esters. Through the illumination   
   and evolution of ketoreductase, the team achieved an enantioselective   
   biocatalytic Giese-type radical conjugate addition to transform fatty   
   acids to a-chiral esters, Zhao said.   
      
   Enantioselectivity is the degree to which an enantiomer -- one of a pair   
   of molecules that are mirror images of each other -- is preferentially   
   produced in a chemical reaction. Chirality is a fundamental feature of   
   organic compounds, which greatly influences the properties of molecules,   
   and its implications are enormous in many areas, including biology,   
   medicine, and material science. For example, the diverse stereochemistry   
   of organic molecules (the spatial arrangement of atoms and its effect   
   on chemical reactions) not only significantly enhances the richness of   
   the biological world, but also plays a profound role in many biological   
   activities such as molecular communication, he said.   
      
   The findings offer practical applications for CABBI's work to develop   
   biofuels and biochemicals from crops like miscanthus, sorghum, and   
   energycane instead of petroleum. The new biocatalytic transformation could   
   use the fatty acids that CABBI is generating from those plants as starting   
   materials to synthesize value-added bioproducts -- such as ingredients   
   for soaps or skin-care products -- in an environmentally friendly way.   
      
   "Although we did not target a specific product for further application,   
   this work provides a practical new method that could be potentially   
   applied to upgrading fatty acids," Zhao said. "Enzymes are the workhorses   
   for biological synthesis of fuels and chemicals from renewable biomass.   
      
   "One of the major scientific changes in CABBI's Conversion research,   
   or bioenergy research in general, is the lack of known enzymes with the   
   desired activity and substrate specificity for the synthesis of target   
   fuels and chemicals. Therefore, there is an urgent need to develop   
   new strategies to discover or engineer enzymes with desired activity   
   or reactivity."  Co-authors on the study included CABBI Postdoctoral   
   Fellow Guangde Jiang of ChBE; CABBI's Wesley Harrison, a Ph.D. candidate   
   in ChBE and IGB; Jianqiang Feng and Binju Wang of Xiamen University,   
   China; and Jiawen Cui, Xin Zang, and Jiahai Zhou of Shanghai Institute   
   of Organic Chemistry, China. Zhou is also affiliated with the Chinese   
   Academy of Sciences Shenzhen Institute of Advanced Technology, China.   
      
      
   ==========================================================================   
   Story Source: Materials provided by   
   University_of_Illinois_at_Urbana-Champaign_Institute_for   
   Sustainability,_Energy,_and_Environment. Note: Content may be edited   
   for style and length.   
      
      
   ==========================================================================   
   Journal Reference:   
      1. Xiaoqiang Huang, Jianqiang Feng, Jiawen Cui, Guangde Jiang, Wesley   
         Harrison, Xin Zang, Jiahai Zhou, Binju Wang, Huimin   
         Zhao. Photoinduced chemomimetic biocatalysis for enantioselective   
         intermolecular radical conjugate addition. Nature Catalysis, 2022;   
         DOI: 10.1038/s41929-022- 00777-4   
   ==========================================================================   
      
   Link to news story:   
   https://www.sciencedaily.com/releases/2022/05/220502170919.htm   
      
   --- up 9 weeks, 10 hours, 50 minutes   
    * Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)   
   SEEN-BY: 15/0 106/201 114/705 123/120 129/330 331 153/7715 218/700   
   SEEN-BY: 229/110 111 317 400 426 428 470 664 700 292/854 298/25 305/3   
   SEEN-BY: 317/3 320/219 396/45   
   PATH: 317/3 229/426