Novel haem-degrading protein

This paper presents a beautiful octameric structure of HbpS, “a novel protein of previously unknown function from Streptomyces reticuli” complexed with iron. The authors “propose that the iron atom originates from the haem group and report subsequent biochemical experiments that demonstrate that HbpS possesses haem-degrading activity in vitro”. In the diagram taken from PDB:3FPW, the iron atoms are represented as grey spheres and phosphate ions are purple/red tetrahedra.