Cloning, expression and identification of phage's capsid Vp3 protein of guinea pig inclusion conjunctivitis chlamydia / 中华传染病杂志

ABSTRACT

Objective To get phagc's capsid Vp3 gene and protein of guinea pig inclusion conjunctivitis (GPIC) chlamydia. Methods The genome DNA was extracted from the φCPG1 phage.The full sequence of Vp3 gene was amplified by polymerase chain reaction (PCR) from the above genome DNA. The Vp3 gene was digested by restriction endonuclease and then inserted into prokaryotic plasmid vector pET30a (+). The recombinant plasmid was transformed into E. coil BL21, and was identified by restriction endonuclease, PCR and sequencing. The E. coil BL21 with expected recombinant plasmid was induced and the expressed recombinant Vp3 protein was identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot, then purified by agarose gel. Results The recombinant gene was sequenced and proved to be 447 bp which was consistent with the φCPG1 Vp3 gene sequence in GenBank. A 25 000 capsid protein was expressed and confirmed by SDS-PAGE and Western blot. The purified protein was obtained. Conclusion The capsid Vp3 protein of φCPG1 is successfully expressed and purified, which is helpful for the further study on its mechanism and clinical applications.