Heterogeneous expression and functional evaluation of in silico characterized recombinant OmpC of Salmonella Typhimurium as a functional poultry vaccine to eradicate zoonotic transmission

Abstract

Salmonellosis is one of the major global health concerns leading to millions of deaths annually. The present vaccines not being up to the mark necessitate the need for the development of new generation vaccines. Outer membrane proteins (Omps) of several Gram negative bacteria have been investigated and found to be immunogenic and protective. The present study explores the potential of a major porin protein (OmpC) of Salmonella Typhimurium, as a vaccine candidate. The OmpC 3D structure and its potential to bind effectively with antibodies and generate humoral response was investigated using in silico docking, and expressed in a heterogeneous Escherichia coli M15 host strain. The rOmpC was purified and its immunopotential was evaluated in vitro by western blotting and in vivo in three weeks old chicks. The recombinant OmpC produced a significant humoral response and in vaccinated birds 100% survival rate was observed along with delay in the shedding of organism in droppings. These findings indicate that the rOmpC vaccination prevents mortality in chicken and lowers fecal shedding in droppings.

Key words: Outer membrane protein (Omp), Salmonellosis, Salmonella Typhimurium, subunit vaccines, porins,rigid-body docking.