The CADD, Chlamydia protein associating with death domains, crystal structure reveals a dimer of seven-helical bundles. Each bundle contains a di-iron centre adjacent to an internal cavity that forms an active site similar to that of methane mono-oxygenase hydrolase [1].

1: Structure of the Chlamydia protein CADD reveals a redox enzyme that modulates host cell apoptosis. Schwarzenbacher R, Stenner-Liewen F, Liewen H, Robinson H, Yuan H, Bossy-Wetzel E, Reed JC, Liddington RC; J Biol Chem. 2004;279:29320-29324. PMID:15087448