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Phage Phenomics: Physiological Approaches to Characterize Novel Viral Proteins
Published on: June 11, 2015
Diverse bacterial pattern recognition receptors sense the core phage proteome
Hyunbin Lee1,2, Sofia Luengo-Woods1,2, Jianxiu Zhang3
1Department of Biochemistry, Stanford University, Stanford, CA, USA.
Nature
|July 29, 2026
Summary
Prokaryotic STAND NTPases are crucial for bacterial immunity against phages. This study identifies 90 families involved in antiviral defense, revealing how bacteria recognize diverse phage proteins for protection.
Area of Science:
- Microbiology
- Immunology
- Structural Biology
Background:
- Cellular immunity relies on recognizing foreign molecules.
- Prokaryotic STAND NTPases are vital for bacterial defense against phages, but their diversity is underexplored.
- Eukaryotic NOD-like receptors are part of the STAND NTPase superfamily involved in cellular immunity.
Purpose of the Study:
- To systematically analyze prokaryotic STAND NTPases and identify families involved in antiviral defense.
- To elucidate the mechanism of recognition of phage proteins by bacterial STAND NTPases.
- To understand the structural basis of bacterial immunity against phages.
Main Methods:
- Systematic phylogenetic analysis of prokaryotic STAND NTPases.
- Cryogenic electron microscopy to determine the structure of the Avs7-MCP complex.
- Genetic screens using a library of phage genes to identify new STAND-mediated recognition pathways.
Main Results:
- Identified at least 90 structurally distinct prokaryotic STAND NTPase families involved in antiviral defense.
- The Avs7 family recognizes the major capsid protein (MCP) of tailed phages, utilizing bacterial elongation factor Tu (EF-Tu).
- Discovered 13 additional STAND families that recognize 13 conserved phage proteins, covering most core components of tailed phages.
Conclusions:
- Bacterial immunity employs structure-based pattern recognition for defense against a wide array of phage proteins.
- Host-factor repurposing is a key mechanism in bacterial antiviral defense.
- This work significantly expands the known repertoire of bacterial immune systems and their targets.
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