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Published on: October 14, 2011
A distinct single-stranded DNA-binding protein encoded by the Lactococcus lactis bacteriophage bIL67
Agnieszka K Szczepanska1, Elena Bidnenko, Danuta Płochocka
1INRA, Laboratoire de Génétique Microbienne, Domaine de Vilvert, 78352 Jouy en Josas Cedex, France.
Virology
|February 24, 2007
Summary
Researchers characterized a novel single-stranded binding protein (SSB) from the Lactococcus lactis phage bIL67. This phage SSB exhibits high affinity for ssDNA, similar to known bacterial SSBs, and possesses a distinct OB-fold structure.
Area of Science:
- Microbiology
- Molecular Biology
- Virology
Background:
- Single-stranded binding proteins (SSBs) are crucial for DNA metabolism in all organisms.
- Characterization of SSBs from bacteriophages, particularly lactococcal phages, is limited.
Purpose of the Study:
- To characterize the SSB protein encoded by the Lactococcus lactis phage bIL67 orf14 gene.
- To determine the DNA-binding properties and structural features of this novel phage SSB.
Main Methods:
- Protein purification and characterization.
- Electrophoretic mobility-shift assays (EMSA) to assess ssDNA binding.
- Gel filtration to determine protein oligomeric state.
- Three-dimensional modeling to predict protein structure.
Main Results:
- The Orf14(bIL67) protein binds non-specifically to single-stranded DNA (ssDNA) with high affinity.
- Mutagenesis and structural analysis suggest an OB-fold structure mediates ssDNA binding.
- The native Orf14(bIL67) protein exists as a homotetramer.
Conclusions:
- Orf14(bIL67) is the first characterized SSB protein from a lactococcal phage.
- This finding establishes a novel cluster of phage SSBs.
- The study provides insights into the potential role of Orf14(bIL67) in the phage life cycle.
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