The oligomerization domain of C4-binding protein (C4bp) acts as an adjuvant, and the fusion protein comprised of the 19-kilodalton merozoite surface protein 1 fused with the murine C4bp domain protects mice against malaria.

Highly purified protein antigens are usually poor immunogens; in practice, adjuvants are needed to obtain satisfactory immune responses. Plasmodium yoelii 19-kDa merozoite surface protein 1 (MSP1(19)) is a weak antigen, but mice vaccinated with this antigen in strong adjuvants can survive an otherwise lethal parasite challenge. Fusion proteins comprising this antigen fused to the oligomerization domain of the murine complement inhibitor C4-binding protein (C4bp) and a series of homologues have been produced.

The toxicity of recombinant proteins in Escherichia coli: a comparison of overexpression in BL21(DE3), C41(DE3), and C43(DE3).

Two mutant strains of Escherichia coli BL21(DE3), called C41(DE3) and C43(DE3) and originally described by Miroux and Walker, are frequently used to overcome the toxicity associated with overexpressing recombinant proteins using the bacteriophage T7 RNA polymerase expression system. Even when the toxicity of the plasmids is so high that it prevents transformation in the strain BL21(DE3), the toxic proteins can often be expressed successfully in C41(DE3) and/or C43(DE3). In this work, using a range of plasmids coding for several types of proteins, we investigated in BL21(DE3), C41(DE3), and C43(DE3) their ability to undergo transformation and to express.