title: Recombinant expression of in silico identified Bcell epitope of epsilon toxin of Clostridium perfringens in translational fusion with a carrier protein.
abstract: Epsilon toxin secreted by Clostridium perfringens types B and D has been directly implicated as the causative agent of fatal enterotoxemia in domestic animals. The aim of the present study is to use in silico approach for identification of B-cell epitope(s) of epsilon toxin, and its expression in fusion with a carrier protein to analyze its potential as vaccine candidate(s). Using different computational analyses and bioinformatics tools, a number of antigenic determinant regions of epsilon toxin were identified. One of the B cell epitopes of epsilon toxin comprising the region (amino acids 40-62) was identified as a promising antigenic determinant. This Etx epitope (Etx40-62) was cloned and expressed as a translational fusion with B-subunit of heat labile enterotoxin (LTB) of E. coli in a secretory expression system. Similar to the native LTB, the recombinant fusion protein retained the ability to pentamerize and bind to GM1 ganglioside receptor of LTB. The rLTB.Etx40-62 could be detected both with anti-Etx and anti-LTB antisera. The rLTB.Etx40-62 fusion protein thus can be evaluated as a potential vaccine candidate against C. perfringens.
  
  
  BACKGROUND
  aa - amino acid(s), Etx - epsilon toxin of Clostridium perfringens, LTB - B-subunit of heat labile enterotoxin of E. coli.
authors.affiliation: Gene Regulation Laboratory, National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi - 110067, India ; Authors equally contributed.
authors.forename: Himani
authors.initials: H
authors.lastname: Kaushik
authors.forename: Sachin
authors.initials: S
authors.lastname: Deshmukh
authors.forename: Deepika Dayal
authors.initials: DD
authors.lastname: Mathur
authors.forename: Archana
authors.initials: A
authors.lastname: Tiwari
authors.forename: Lalit C
authors.initials: LC
authors.lastname: Garg
keywords: Bioinformatics; Clostridium perfringens; Epitope; Epitope prediction algorithms; Epsilon toxin; LTB; fusion protein; in silico; vaccine
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