Plasma kallikrein therefore is composed of a heavy chain and a light chain held together by a disulfide bond .
Plasma prekallikrein is converted to plasma kallikrein by factor XIIa by the cleavage of an internal Arg - Ile bond .
Plasma kallikrein is composed of a heavy chain and a light chain held together by a disulfide bond .
Plasma prekallikrein is converted to plasma kallikrein by factor XIIa by the cleavage of an internal Arg - Ile bond .