Characterization of vector elements and soluble expression of PCV3  cap protein in Kluyveromyces marxianus

Due to thermotolerance and rapid growth yeast Kluyveromyces marxianus ( K.marxianus ) is emerging as a new platform organism for production of recombinant proteins. We constructed an expression vector to express exogenous proteins. Firstly, qPCR was used to validate the expression efficiency of endogenous promoters. Selecting PDC1 as the promoter to initiate the expression of EGFP for validation, the vector could successfully express foreign proteins. With Hygromycin in the medium the vector can accumulate in the cell. Further construction the cap of porcine circovirus type 3  ( PCV3 ) was carried out on the vector, and soluble PCV3  cap protein was obtained. Under electron microscopy, PCV3  cap formed viral like particles(VLP). This study successfully constructed the expression vector and elements of K.marxianus , which can further promote the research on the expression of exogenous proteins in K.marxianus . The soluble expression of PCV3  cap and formed VLP structure laid the foundation for further developing PCV3  vaccines.