Biosynthesis of Strained Amino Acids Through a PLP-Dependent Enzyme via Cryptic Halogenation
Max B Sosa1, Jacob T Leeman1, Lorenzo J Washington2
1Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720 USA.
Biorxiv : the Preprint Server for Biology
|January 3, 2024
Summary
Researchers discovered a new non-canonical amino acid, pazamine, with a unique cyclopropane ring. This finding may advance specialty chemical production and agricultural biotechnology.
Area of Science:
- Biochemistry and Organic Chemistry
- Plant Science and Agricultural Biotechnology
Background:
- Amino acids (AAs) are fundamental building blocks for proteins and natural products.
- Non-canonical amino acids (ncAAs) offer diverse structural features beyond the 20 proteinogenic AAs.
- Understanding ncAA biosynthesis pathways can unlock novel chemical entities.
Approach:
- Discovery and elucidation of the pazamine biosynthetic pathway in *Pseudomonas azotoformans*.
- Characterization of the radical halogenase PazA and pyridoxal-5'-phosphate-dependent enzyme PazB.
- Genetic studies in *Arabidopsis thaliana* to assess the biological activity of pazamine and its derivatives.
Key Points:
- A novel ncAA, pazamine, featuring a two-step cyclopropane ring formation from lysine was identified.
- Pazamine and its derivative pazamide show potential to inhibit ethylene biosynthesis in plants.
- The enzyme PazB can be engineered for biocatalytic synthesis of cyclobutane-containing AAs.
Conclusions:
- The discovery of the pazamine pathway expands the known repertoire of ncAA biosynthesis.
- Pazamine and its derivatives hold promise for agricultural applications, potentially modulating plant growth.
- This work opens avenues for biocatalytic production of novel amino acids and specialty chemicals.
Keywords:
biosynthesiscyclobutanecyclopropanehalogenasenon-canonical amino acidspyridoxal phosphate (PLP)More Related Videos
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