American Journal of Microbiological Research
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American Journal of Microbiological Research. 2017, 5(6), 131-137
DOI: 10.12691/ajmr-5-6-3
Open AccessArticle

Cloning, Sequencing and Production of Recombinant Polyclonal Antibodies against Egyptian Staphylococcal Enterotoxin A

H. A. Nour El-Din1, , M. N. Abu El-Naga2, M. E. El-Fouly2, M. K. Ibrahim3, E. H. El-Shatoury3 and H. A. Hussein2

1Agricultural Genetic Engineering Research Institute (AGERI)

2National Center for Radiation Research and Technology, Atomic Energy Authority, Cairo, Egypt

3Faculty of Science, Ain Shams University

Pub. Date: December 08, 2017

Cite this paper:
H. A. Nour El-Din, M. N. Abu El-Naga, M. E. El-Fouly, M. K. Ibrahim, E. H. El-Shatoury and H. A. Hussein. Cloning, Sequencing and Production of Recombinant Polyclonal Antibodies against Egyptian Staphylococcal Enterotoxin A. American Journal of Microbiological Research. 2017; 5(6):131-137. doi: 10.12691/ajmr-5-6-3


Staphylococcus aureus (S.aureus) is the most common pathogen found in hospitals, community-acquired infections and colonizes up to 50% of humans, including mucous membranes and damaged skin. Some strains produce enterotoxins (Ent) as staphylococcal enterotoxin A (SEA) which is involved in 75% of food poisoning outbreaks. Few methods are sensitive and specific enough to confirm the diagnosis of staphylococcal food poisoning. In this study, a segment of Ent A-ORF with molecular weight 774 bp was amplified, cloned, sequenced and aligned with published Ent A-ORFs. Ent A-ORF was subcloned into bacterial expression vector (GST-PGEX4T1 vector) and expressed as a fusion protein with GST-tagged protein. A band size of 27 kDa of purified Ent A protein was cleaved from GST protein by thrombin. The expressed protein of Ent A was identified by strong reaction with commercialized polyclonal antibodies against Ent A. Antiserum against Egyptian recombinant Ent A protein was produced by immunization of Balb/c mice, the produced recombinant polyclonal antibodies had a titre of 1:2500 in direct ELISA. The produced recombinant polyclonal antibody was evaluated and reacted specifically in Western immunoblotting analysis and ELISA test. Finally from the obtained results, the produced recombinant protein of Ent A can be used successfully for production of recombinant polyclonal antibodies and used in large-scale detection of staphylococcal enterotoxin A.

staphylococcus aureus Ent A cloning and expression ELISA polyclonal antibody

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