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Recombinant Protein Expression, Crystallization, and Biophysical Studies of a Bacillus-conserved Nucleotide Pyrophosphorylase, BcMazG
Published on: May 16, 2017
Functional expression of Bacillus anthracis protective antigen in E. coli
Fatemeh Vahedi1, Mojtaba Sankian, Mahmoud Mahmoudi
1Razi Vaccine & Serum Research Institute, Ahmadabad Street, P.O. Box 91735-174, Mashhad, Iran. f.vahedi@rvsri.ir
Applied Biochemistry and Biotechnology
|July 26, 2008
Summary
Recombinant protective antigen (rPA) from Bacillus anthracis was successfully produced and purified. This rPA demonstrated immunogenicity in mice and provided protection against anthrax infection, highlighting its potential as a vaccine candidate.
Area of Science:
- Biotechnology
- Immunology
- Microbiology
Background:
- Bacillus anthracis protective antigen (PA) is a key immunogen and vaccine candidate.
- Low PA production and purification challenges necessitate recombinant methods.
- PA is crucial for anthrax toxin activity and immune response.
Purpose of the Study:
- To produce recombinant PA (rPA) as a potential vaccine.
- To evaluate the immunogenicity and protective efficacy of rPA.
- To develop a scalable method for rPA production.
Main Methods:
- Cloning of B. anthracis PA (amino acids 175-764) into pET21b(+) plasmid.
- Expression of rPA in Escherichia coli BL21 after induction.
- Purification of rPA using anti-T7.tag affinity chromatography.
- Confirmation of rPA specificity via electrophoresis and Western blotting.
- Immunization of BALB/c mice with rPA and assessment of antibody response.
- Challenge studies with virulent B. anthracis to evaluate protection.
Main Results:
- Constructed plasmid integrity confirmed by restriction enzyme mapping.
- Specific rPA expression achieved in E. coli.
- Purified rPA confirmed by Western blotting.
- Immunization induced specific immunoglobulin G antibodies against PA in mice.
- rPA immunization conferred protection against a virulent B. anthracis challenge.
Conclusions:
- The developed method successfully produced immunogenic and protective rPA.
- rPA holds significant potential as a recombinant vaccine against anthrax.
- Further studies are warranted to optimize rPA for widespread vaccine use.
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