Expression of Coxsackievirus B4 proteins VP0 and 2C in Escherichia coli and generation of virus protein recognizing antisera

Abstract

Coxsackievirus B4 (CBV-4) capsid protein VP0 and non-structural 2C protein were expressed and purified using a glutathione-S-transferase (GST) fusion protein expression system. We used a full-size CBV-4 cDNA as a template to amplify the genes by polymerase chain reaction (PCR). The genes were cloned into expression vector pGEX-2T and expressed as a fusion protein with GST. The GST-fusion proteins (GST-2C and GST-VP0) were purified in denatured and native forms and used to generate antibodies in rabbits. The antisera raised against GST-VP0 fusion protein recognized the corresponding structural proteins (VP0, VP2 and VP4) from purified CBV-4 preparations and infected cell lysates. In addition, cross-reactivity with CAV-9 and CBV-5 capsid proteins was observed. Anti-GST-2C antisera precipitated viral 2C protein in CBV-4-infected GMK cells, showing that the antibodies recognize the corresponding natural antigen.