Title : Structure of and influence of a tick complement inhibitor on human complement component 5
Abstract :
- To provide insight into the structural and functional properties of human complement component 5 (C5 ), we determined its crystal structure at a resolution of 3.1 A
- The core of C5 adopted a structure resembling that of C3, with the domain arrangement at the position corresponding to the C3 thioester being very well conserved
- However, in contrast to C3, the convertase cleavage site in C5 was ordered and the C345C domain flexibly attached to the core of C5
- Binding of the tick C5 inhibitor OmCI to C5 resulted in stabilization of the global conformation of C5 but did not block the convertase cleavage site
- The structure of C5 may render possible a structure-based approach for the design of new selective complement inhibitors