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Title: Reversing the Enantioselectivity of Enzymatic Carbene N−H Insertion Through Mechanism‐Guided Protein Engineering**
Abstract

We report a computationally driven approach to access enantiodivergent enzymatic carbene N−H insertions catalyzed by P411 enzymes. Computational modeling was employed to rationally guide engineering efforts to control the accessible conformations of a key lactone‐carbene (LAC) intermediate in the enzyme active site by installing a new H‐bond anchoring point. This H‐bonding interaction controls the relative orientation of the reactive carbene intermediate, orienting it for an enantioselectiveN‐nucleophilic attack by the amine substrate. By combining MD simulations and site‐saturation mutagenesis and screening targeted to only two key residues, we were able to reverse the stereoselectivity of previously engineeredS‐selective P411 enzymes. The resulting variant,L5_FL‐B3, accepts a broad scope of amine substrates for N−H insertion with excellent yields (up to >99 %), high efficiency (up to 12 300 TTN), and good enantiocontrol (up to 7 : 93er).

 
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Award ID(s):
2016137
NSF-PAR ID:
10442229
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
62
Issue:
35
ISSN:
1433-7851
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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