Structural Biochemistry Group, The University of Edinburgh, UK.
A structure of residues 1-177 of the cyclophilin domain of a large divergent cyclophilin from the filarial nematode parasite Brugia malayi has been crystallised and solved in two different crystal forms. The active site has a similar structure to that of human cyclophilin A. Two of the 13 residues important in forming the human cyclophilin A/cyclosporin A complex are altered in the B. malayi cyclophilin and explain the relatively poor inhibition of peptidyl prolyl isomerase activity by cyclosporin A.