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Updated: May 26, 2026
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Generating Transposon Insertion Libraries in Gram-Negative Bacteria for High-Throughput Sequencing
Published on: July 7, 2020
Endolysins, Depolymerases, Holins, and VALs: Phage-Derived Proteins for Combating Antimicrobial Resistance
Zahra Nasiri Shoeibi1, Farzaneh Rafiee2, Sousan Akrami1
1Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
Microbial Drug Resistance (Larchmont, N.Y.)
|May 25, 2026
Summary
Bacteriophage-derived enzymes like holins and endolysins offer novel antibacterial strategies against multidrug-resistant bacteria. These proteins, including depolymerases and virion-associated lysins, show promise in combating resistant infections.
Area of Science:
- Microbiology
- Biotechnology
- Infectious Diseases
Background:
- The increasing prevalence of multidrug-resistant (MDR) bacteria necessitates novel therapeutic approaches.
- Bacteriophages encode various lytic enzymes with antibacterial potential.
Purpose of the Study:
- To review the molecular mechanisms, advantages, limitations, and therapeutic applications of bacteriophage-derived lytic proteins against MDR infections.
- To highlight the potential of engineered phage enzymes as alternative antibacterials.
Main Methods:
- Review of existing literature on bacteriophage-encoded lytic proteins.
- Analysis of the distinct mechanisms of action for holins, endolysins, polysaccharide depolymerases, and virion-associated lysins (VALs).
- Discussion of natural and engineered forms of these enzymes, including "artilysins" and "chimeolysins".
Main Results:
- Phage lytic proteins disrupt bacterial cells or protective barriers through diverse mechanisms.
- Endolysins lyse Gram-positive bacteria and can be engineered for Gram-negative efficacy.
- Depolymerases degrade bacterial polysaccharides, while VALs facilitate phage DNA entry.
Conclusions:
- Phage-derived enzymes demonstrate rapid, specific bacteriolysis with low resistance potential.
- Challenges in delivery, stability, and immunogenicity require further research for therapeutic application.
- These enzymes represent a promising avenue for combating MDR bacterial infections.
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