Kazal domain found in factor I-like modules (FIMs) region on the carboxyl-terminal of complement component C7 proteins. Complement component C7 is a subunit of the membrane attack complex (MAC), a fundamental machinery in the mammalian innate immunity. KAZAL domains are common in serine protease inhibitors [1].

1: Solution structure of factor I-like modules from complement C7 reveals a pair of follistatin domains in compact pseudosymmetric arrangement. Phelan MM, Thai CT, Soares DC, Ogata RT, Barlow PN, Bramham J; J Biol Chem. 2009;284:19637-19649. PMID:19419965