Co-expression of chaperones from P. furiosus enhanced the soluble expression of the recombinant hyperthermophilic α-amylase in E. coli.

The extracellular α-amylase from the hyperthermophilic archaeum Pyrococcus furiosus (PFA) is extremely thermostable and of an industrial importance and interest. PFA aggregates and accumulates as insoluble inclusion bodies when expressed as a heterologous protein at a high level in Escherichia coli. In the present study, we investigated the roles of chaperones from P. furiosus in the soluble expression of recombinant PFA in E. coli. The results indicate that co-expression of PFA with the molecular chaperone prefoldin alone significantly increased the soluble expression of PFA. Although, co-expression of other main chaperone components from P. furiosus, such as the small heat shock protein (sHSP) or chaperonin (HSP60), was also able to improve the soluble expression of PFA to a certain extent. Co-expression of chaperonin or sHSP in addition to prefoldin did not further increase the soluble expression of PFA. This finding emphasizes the biotechnological potentials of the molecular chaperone prefoldin from P. furiosus, which may facilitate the production of recombinant PFA.