Related Experiment Video
Updated: Jan 24, 2026
06:50
Author Spotlight: A Computational Approach to Decipher Amino Acid Preferences in Multispecific Protein-Protein Interactions
Published on: January 26, 2024
2.5K
Involvement of Peptide Epimerization in Poly-γ-glutamic Acid Biosynthesis
Yasushi Ogasawara1, Mayuko Shigematsu1, Shota Sato1
1Graduate School of Engineering , Hokkaido University , Sapporo , Hokkaido 060-8628 , Japan.
Organic Letters
|May 16, 2019
Summary
Poly-γ-glutamic acid (PGA) biosynthesis involves a complex enzyme system. Isotope tracer experiments reveal that epimerization of the growing peptide chain is key to incorporating d-glutamic acid residues into PGA.
Area of Science:
- Biochemistry
- Polymer Science
- Microbiology
Background:
- Poly-γ-glutamic acid (PGA) is a versatile biopolymer with d- and l-glutamic acid (Glu) residues linked by amide bonds.
- PGA synthesis occurs via a transmembrane enzyme complex (PgsB, PgsC, PgsA).
- The precise mechanism, particularly the incorporation of d-Glu, remains largely unknown.
Purpose of the Study:
- To elucidate the mechanism of d-glutamic acid incorporation during Poly-γ-glutamic acid biosynthesis.
- To investigate the role of epimerization in PGA production.
Main Methods:
- Utilized isotope tracer experiments with deuterated l-glutamic acid and d-glutamic acid.
- Analyzed the incorporation of labeled amino acids into the PGA polymer.
Main Results:
- Demonstrated that epimerization of the growing peptide chain is an integral part of PGA biosynthesis.
- Provided direct evidence for the mechanism of d-Glu residue introduction.
Conclusions:
- The study clarifies a critical step in PGA synthesis, identifying epimerization as the source of d-Glu residues.
- This finding advances our understanding of microbial polymer production and enzyme mechanisms.
More Related Videos
15:33Microwave-assisted Functionalization of Polyethylene glycol and On-resin Peptides for Use in Chain Polymerizations and Hydrogel Formation
Published on: October 29, 2013
29.7K
11:56Antimicrobial Peptides Produced by Selective Pressure Incorporation of Non-canonical Amino Acids
Published on: May 4, 2018
13.0K
Related Concept Videos
01:28Biosynthesis of Nucleic Acids
1.0K
Nucleic acid biosynthesis is a fundamental biochemical process that produces the purine and pyrimidine nucleotides essential for DNA and RNA synthesis. This pathway maintains a balanced nucleotide pool, preventing imbalances that could jeopardize genetic integrity and cellular function. Given the crucial role of nucleotides, their synthesis is tightly regulated to ensure proper cellular homeostasis.Purine BiosynthesisThe biosynthesis of purine nucleotides begins with ribose-5-phosphate, a...
1.0K
02:43Peptide Bonds
82.5K
A peptide bond covalently attaches amino acids through a dehydration reaction. One amino acid's carboxyl group and another amino acid's amino group combine, releasing a water molecule. The resulting bond is the peptide bond. The products that such linkages form are peptides. As more amino acids join this growing chain, the resulting chain is a polypeptide. Each polypeptide has a free amino group at one end. This end has the N-terminal, or the amino-terminal, and the other end has a free...
82.5K
01:24Biosynthesis in Bacteria
598
Biosynthesis in bacteria is a fundamental anabolic process that generates essential macromolecules, including proteins, nucleic acids, lipids, and polysaccharides. These macromolecules are critical for cellular growth, replication, and function. The process is tightly regulated and energetically linked to catabolic pathways to ensure optimal resource utilization.Biosynthetic pathways begin with precursor metabolites such as pyruvate, acetyl-CoA, and glucose-6-phosphate derived from glycolysis,...
598
01:26Biosynthesis of Polysaccharides
590
Polysaccharides such as glycogen and starch are synthesized from nucleoside diphosphate sugars, primarily uridine diphosphate glucose (UDPG) and adenosine diphosphate glucose (ADPG). These activated glucose donors act as key intermediates in carbohydrate metabolism and biosynthesis. UDPG primarily involves glycogen synthesis in animals and many bacteria, while ADPG plays a fundamental role in starch synthesis in plants and certain bacteria.UDPG is formed when glucose-1-phosphate reacts with...
590
01:29Biosynthesis of Lipids
561
Microbial membranes exhibit remarkable diversity in lipid composition, reflecting evolutionary adaptations to various environmental conditions. The three domains of life—Bacteria, Archaea, and Eukarya—synthesize membrane lipids through distinct biosynthetic pathways, leading to fundamental structural differences that impact membrane stability, function, and adaptability.Fatty Acid-Based Lipids in Bacteria and EukaryaBacteria and eukaryotes share a common fatty acid biosynthesis...
561
03:42Amino acids
104.8K
Amino acids are the monomers that comprise proteins. Each amino acid has the same fundamental structure, which consists of a central carbon atom, or the alpha (α) carbon, bonded to an amino group (NH2), a carboxyl group (COOH), and to a hydrogen atom. Every amino acid also has another atom or group of atoms bonded to the central atom known as the R group. There are 20 common amino acids present in proteins, each with a different R group. Variation in the amino acid sequence is responsible for...
104.8K