Previously, we developed a single recombinant protein vaccine against plague composed of a fusion between the Fraction 1 (F1) capsular antigen and the V antigen. To determine whether the overall expression, solubility, and recovery of the F1 fusion protein -V could be improved, we modified the original fusion. Standard recombinant Yersinia pestis DNA techniques were used to reverse the gene order so that the V antigen coding sequence was fused at its C-terminus to the N-terminus of F1.

The F1 secretion signal sequence (F1S) was subsequently fused to the N-terminus of V. This new fusion protein, designated F1S-V-F1, was then co-expressed with the Y. pestis periplasmic chaperone protein Caf1M in BL21- Star Escherichia coli. Recombinant strains expressing F1-V, F1S-F1-V, or F1S-V-F1 were compared by cell fractionation, SDS-PAGE, Western blotting, and suspension immunolabeling.

F1S-V-F1 showed increased solubility and secretion when co-expressed with Caf1M, resulting in a recombinant protein that is processed similarly to the native F1 protein. Purification of F1S-V-F1 was performed by anion exchange and hydrophobic interaction chromatography. The purification method produced more than 1 mg of purified soluble protein per litre of culture-induced. The polymerization characteristics of F1S-V-F1 were comparable to those of native F1. The purified F1S-V-F1 protein appeared equivalent to F1-V in its ability to be recognized by neutralizing antibodies.

Product name

Recombinant Yersinia pestis F1 antigen protein (His tag)

Purity: > 90% SDS-PAGE.

Expression system: Escherichia coli

Accession: P26948

Protein length: full length protein

Animal-free: No

Nature: recombinant

Species: Yersinia pestis

Predicted Molecular Weight: 18kDa

Amino acids: 22 to 170

Tags: Your N-Terminus Tag

Additional sequence information

Full-length mature chain without the signal peptide.


Our Abpromise warranty covers the use of ab236940 in the following tested applications. Application notes include recommended starting dilutions; the end-user must determine the optimal dilutions/concentrations.

Applications: SDS PAGE

Form: Liquid

Concentration: 100 µg to 0.5 mg/mL

Stability and Storage

Shipped at 4°C. Store at -20°C or -80°C. Avoid freeze/thaw cycle.

  • pH: 7.2
  • Components: Tris buffer, 50% glycerol (glycerin, glycerin)
Categories: Blog