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Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs
Published on: January 17, 2020
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Substrate Sequence Controls Regioselectivity of Lanthionine Formation by ProcM
Tung Le1, Kevin Jeanne Dit Fouque2, Miguel Santos-Fernandez2
1Department of Chemistry and Howard Hughes Medical Institute, University of Illinois at Urbana-Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, United States.
Journal of the American Chemical Society
|November 1, 2021
Summary
Cyanobacteria use a single enzyme to create diverse lanthipeptides from many precursor peptides. Substrate sequences, not the enzyme, dictate lanthionine cross-linking patterns, aiding future prediction models.
Area of Science:
- Biochemistry
- Molecular Biology
- Synthetic Biology
Background:
- Lanthipeptides are ribosomally synthesized and post-translationally modified peptides (RiPPs) crucial for stability and bioactivity.
- Cyanobacteria exhibit unique combinatorial biosynthesis, producing numerous lanthipeptides from diverse precursor peptides using a single lanthionine synthetase.
- The mechanism by which a single enzyme controls cyclization for numerous substrates remains unclear.
Purpose of the Study:
- Investigate the factors governing lanthionine cross-linking regioselectivity in cyanobacterial lanthipeptide biosynthesis.
- Evaluate trapped ion mobility spectrometry-tandem mass spectrometry (TIMS-MS/MS) for separating lanthipeptide isomers.
- Establish a foundation for predicting lanthipeptide ring patterns from combinatorial biosynthesis.
Main Methods:
- Utilized a library of ProcA3.3 precursor peptide variants.
- Employed trapped ion mobility spectrometry-tandem mass spectrometry (TIMS-MS/MS) for isomer separation.
- Analyzed substrate sequences and enzyme activity (ProcM).
Main Results:
- Substrate peptide sequences, rather than the enzyme ProcM, determine the regioselectivity of lanthionine formation.
- TIMS-MS/MS effectively separated lanthipeptide constitutional isomers, outperforming conventional liquid chromatography.
- Identified key factors for cyclization outcome but found no simple predictive rules for all sequences.
Conclusions:
- Cyanobacterial lanthipeptide cyclization is primarily substrate-dependent.
- TIMS-MS/MS is a valuable tool for analyzing complex lanthipeptide mixtures.
- Future deep learning models can be developed to predict lanthipeptide ring patterns in combinatorial biosynthesis.
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