Solubility as a limiting factor for expression of hepatitis A virus proteins in insect cell-baculovirus system

Abstract

The use of recombinant proteins may represent an alternative model to inactivated vaccines against hepatitis A virus (HAV). The present study aimed to express the VP1 protein of HAV in baculovirus expression vector system (BEVS). The VP1 was expressed intracellularly with molecular mass of 35 kDa. The VP1 was detected both in the soluble fraction and in the insoluble fraction of the lysate. The extracellular expression of VP1 was also attempted, but the protein remained inside the cell. To verify if hydrophobic characteristics would also be present in the HAV structural polyprotein, the expression of P1-2A protein was evaluated. The P1-2A polyprotein remained insoluble in the cellular extract, even in the early infection stages. These results suggest that HAV structural proteins are prone to form insoluble aggregates. The low solubility represents a drawback for production of large amounts of HAV proteins in BEVS.

Structural Analysis of Avian Encephalomyelitis Virus Polyprotein for Development of Multi Epitopes Vaccine Using Immunoinformatics Approach

“…The formation of insoluble protein particles may hinder the vaccine protein native form. In addition, purification of the vaccine construct may cause structural alterations during solubilization and refolding steps [Silva et al 2016;Dill and Shortle 1991]. Thus the study of the solubility of the vaccine construct is a cornerstone in determining the vaccine nature.…”