Related Experiment Video
Updated: Aug 22, 2026
Expression of Recombinant Proteins in the Methylotrophic Yeast Pichia pastoris
Published on: February 25, 2010
[Gene optimization is necessary to express HPV type 6 L1 protein in the methylotrophic yeast Pichia pastoris]
Ping-chuan Li1, Xiao-guang Zhang, Ling Zhou
1Institute for Viral Disease Control and Prevention, China CDC, Beijing 100052, China.
Objective:
Human papillomavirus 6 (HPV 6) causes genital warts, a common sexually transmitted disease. L1-capsids protein is a highly promising vaccine candidate that has entered phase II clinical trial. But the existing methodologies for producing L1-capsids in insect cells is expensive for use in developing countries. As methylotrophic yeast,the Pichia pastoris expression system offers economy,and high expression levels. Over-expression of HPV6-L1 protein in P. pastoris was the purpose of this study.
Methods:
The whole L1 gene with preferred codons for P. pastoris was rebuilt and A-T rich regions were abolished, Cloning into pPIC3.5K,electroporation of KM71, in vivo screen of multiple inserts by G418 resistance, PCR analysis of pichia integrants, BMGY/BMMY are used for induction and expression of L1 proteins.
Results:
Three clones were found to produce L1 protein which can be identified with Western blot. Compared with L1 protein from E.coli, pichia-produced L1 has some glycosylation. Reacting strongly with MabH6B10.5 in indirect immunofluorescence assay indicated that L1 protein expressed in pichia cell holds its native conformational epitopes which is important for vaccine use. A total 125 microg pure L1 protein could be obtained from 1L cultures through ion-exchange and Ni-NTA chromatography.
Conclusion:
HPV type 6 L1 protein expressed in Pichia pastoris will facilitate the HPV vaccine development and structure-function study.
