Expression cloning and biochemical characterizations of recombinant cyclophilin proteins from Schistosoma mansoni

Recombinant Schistosoma mansoni cyclophilin proteins of the A and the B subtypes (SmCYP A and B) mere expressed in bacterial cells as histidine-and maltose-binding fusion proteins and also as nonfused proteins. in addition, S. mansoni CYPs were produced in Sf9 insect cells in their natural forms. Purified recombinant SmCYP B mas found to possess a peptidyl-prolyl cis-trans isomerase (PPIase) activity, with a k(cat)/K-m value of 8.2 x 10(5) M-1 s(-1). The SmCYP B isoform is approximately two to three times more active than SmCYP k SmCYP B-specific RNA appears to be more abundant in adult schistosomes than SmCYP A RNA in Northern blots. These results support the conclusion that SmCYP B represents the major schistosomal CYP. The PPIase-associated activity of both CYPs was inhibitable by the immunosuppressive drug cyclosporin A (CsA). We attempt to explain differences in PPIase activities and in CsA inhibition by examining models of the two CYPs complexed to CsA. (C) 1998 Academic Press.