Enzyme Engineering for High‐Yielding Amide Formation: Lipase‐Catalyzed Synthesis of <i>N</i>‐Acyl Glycines in Aqueous Media
Glen Kai Bin Kua, Giang K. T. Nguyen, Zhi Li
Abstract
Abstract Amide syntheses remain a key challenging green chemistry reaction. For instance, green synthesis of N ‐acyl glycines as biosurfactants and therapeutics is highly desirable to replace chemical pathways using toxic phosgene. Herein, we report a novel concept for enzymatic amidation in an aqueous system via glycerol activation of fatty acids and theirsubsequent aminolysis with glycine to synthesize N ‐acyl glycines. We then engineer an enzyme (proRML) by reshaping its catalytic pocket to enhance its aminolysis activity and catalytic efficiency by 103‐fold and 465‐fold, respectively. The evolved proRML (D156S/L258K/L267N/S83D/L58K/R86K/W88V) catalyzed the amidation of a fatty acid with glycine to give N ‐lauroylglycine with high yield (80 %). It accepts a broad range of medium‐ to long‐chain fatty acids (C 8 –C 18 ), giving high yields of N ‐decanoyl‐, N ‐myristoyl‐, and N ‐oleoylglycine. The developed amidation concept may be general, and the engineered enzyme is useful for the green synthesis of N ‐acyl glycines.