Abstract: This disclosure concerns compositions and methods for the treatment and inhibition of infectious disease, particularly bubonic and pneumonic plague. In certain embodiments, the disclosure concerns immunogenic proteins, for instance substantially monodisperse F1-V fusion proteins, that are useful for inducing protective immunity against Y. pestis.

Abstract: The invention provides processes and compositions for fermentation, recovery and purification of recombinant bacterial superantigens (rSAgs), exemplified by a recombinant staphylococcal enterotoxin B SEB protein mutated for use in administration to mammalian recipient. This process generates an economically viable quantity of rSEB vaccine protein meeting FDA parenteral drug specifications. The purification methods generally involve multiple steps including hydrophobic interaction chromatography (HIC), buffer exchange (desalting), and cation exchange. The final product of the purification is a highly purified rSAg composition satisfying clinical safety criteria and is immunogenic and protective against lethal aerosol challenge in a murine model.