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Phage Phenomics: Physiological Approaches to Characterize Novel Viral Proteins
Published on: June 11, 2015
Identifying active phage lysins through functional viral metagenomics.
Jonathan E Schmitz1, Raymond Schuch, Vincent A Fischetti
1Rockefeller University, Laboratory of Bacterial Pathogenesis and Immunology, 1230 York Ave., Box 172, New York, NY 10065, USA. jschmitz@rockefeller.edu
Applied and Environmental Microbiology
|September 21, 2010
Summary
Researchers developed a new method to find and clone phage lytic enzymes from uncultured viruses in environmental DNA. This technique successfully identified 26 novel enzymes with biotechnological potential from a fecal viral metagenome.
Area of Science:
- Virology
- Biotechnology
- Genomics
Background:
- Metagenomic sequencing reveals novel bacteriophage diversity and ecological roles.
- Viral metagenomes are a potential source of valuable recombinant proteins.
- Identifying functional proteins from uncultured viruses remains challenging.
Purpose of the Study:
- To develop and validate a novel screening technique for cloning phage lytic enzymes from uncultured viral DNA.
- To explore the biotechnological potential of recombinant proteins from viral metagenomes.
- To characterize novel lysins from uncultured phages.
Main Methods:
- A two-step plasmid-based screening approach was devised.
- Primary screen: Identification of Escherichia coli clones showing colony lysis (hemolytic effect on blood agar) after induction.
- Secondary screen: Direct assay for lytic enzyme activity against autoclaved Gram-negative bacteria (Pseudomonas aeruginosa).
Main Results:
- The method was successfully applied to a viral metagenomic library from animal feces.
- 26 actively expressed lytic enzymes were cloned.
- Identified enzymes include Gram-positive-like, Gram-negative-like, and atypical lysins.
Conclusions:
- This study presents one of the first functional screens of a viral metagenomic population.
- The developed method provides a general approach for characterizing lysins from uncultured phages.
- The findings highlight the biotechnological potential of viral metagenomic resources.
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