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Structural proteins of Enterococcus faecalis bacteriophage ϕEf11
Roy H Stevens1, Hongming Zhang1, Chaiwing Hsiao2
1Laboratory of Oral Infectious Diseases, Temple University Kornberg School of Dentistry, Philadelphia, PA, USA; Department of Endodontics, Temple University Kornberg School of Dentistry, Philadelphia, PA, USA.
Bacteriophage
|January 17, 2017
Summary
Researchers characterized bacteriophage ϕEf11 from Enterococcus faecalis. Mass spectrometry confirmed predicted functions for key structural proteins, including scaffold, major head, major tail, and antireceptor proteins.
Area of Science:
- Virology
- Molecular Biology
- Microbiology
Background:
- Enterococcus faecalis is a significant opportunistic pathogen, often associated with persistent infections like those in root canals.
- Bacteriophages, viruses that infect bacteria, are potential therapeutic agents against bacterial infections.
- The temperate Siphoviridae bacteriophage ϕEf11 was isolated from an E. faecalis. faecalis root canal isolate.
Purpose of the Study:
- To analyze the genomic organization and structural proteins of the bacteriophage ϕEf11.
- To correlate deduced gene functions from sequence analysis with experimentally determined viral proteins.
- To validate the predicted roles of specific open reading frames (ORFs) involved in phage structure assembly.
Main Methods:
- Isolation and induction of bacteriophage ϕEf11 from Enterococcus faecalis.
- Genome sequencing and analysis to identify gene modules for head and tail structure assembly.
- Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) to analyze virion proteins.
- Mass spectrometry (MS) analysis of selected protein bands to determine amino acid sequences.
Main Results:
- Sequence analysis revealed distinct gene modules for head (8 genes) and tail (10 genes) assembly.
- SDS-PAGE of ϕEf11 virions identified 11 distinct protein bands.
- Mass spectrometry analysis confirmed the identity of 5 proteins, matching predicted sequences for ORF8 (scaffold protein), ORF10 (major head protein), ORF15 (major tail protein), and ORF23 (antireceptor).
Conclusions:
- The study successfully linked genomic predictions with proteomic data for bacteriophage ϕEf11.
- The identified proteins are crucial components of the phage's structural assembly machinery.
- These findings contribute to understanding the molecular biology of E. faecalis bacteriophages and their potential applications.
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