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Recombinant Protein Expression, Crystallization, and Biophysical Studies of a Bacillus-conserved Nucleotide Pyrophosphorylase, BcMazG
Published on: May 16, 2017
The Bacillus anthracis chromosome contains four conserved, excision-proficient, putative prophages
Shanmuga Sozhamannan1, Michael D Chute, Farrell D McAfee
1Biological Defense Research Directorate, Naval Medical Research Center, 503 Robert Grant Avenue, Silver Spring, Maryland 20852, USA. sozhamannans@nmrc.navy.mil
BMC Microbiology
|April 8, 2006
Summary
Bacillus anthracis contains four unique prophages, distinguishing it from related bacteria. These prophages can excise but are defective, unable to produce active phage particles.
Area of Science:
- Microbiology
- Genomics
- Bacteriology
Background:
- Bacillus anthracis is a recent clone within the Bacillus cereus sensu lato group.
- The B. anthracis genome harbors four putative lambdoid prophages.
- Understanding the uniqueness and activity of these prophages is crucial.
Purpose of the Study:
- To determine if the four lambdoid prophages are unique to B. anthracis.
- To investigate whether these prophages can produce active phages.
Main Methods:
- Screening over 300 B. anthracis and related isolates using PCR for prophage DNA.
- Employing PCR-based assays to detect prophage excision (attP and attB sites).
- Utilizing SYBR-green real-time PCR to quantify excision frequency and electron microscopy to detect phage particles.
Main Results:
- All tested B. anthracis isolates contained all four prophage regions, while non-B. anthracis isolates did not.
- Prophage excision occurred at low frequencies (2 x 10(-5) - 8 x 10(-8)/cell), significantly increased by mitomycin C induction.
- No viable phage particles were released, cells did not lyse, and no phage particles were observed under electron microscopy after induction.
Conclusions:
- The presence of all four prophage regions in B. anthracis supports its recent emergence.
- These prophage regions can serve as markers to differentiate B. anthracis from its relatives.
- While capable of excision, the four prophages are defective and do not produce infectious phage particles.
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