Peroxide-utilizing biocatalysts: structural and functional diversity of heme-containing enzymes.
Heme-containing enzymes, such as peroxidases, catalase and peroxygenase P450 all utilize peroxides for their specific reactions. A variety of reactions catalyzed by such heme-containing enzymes involve a common, highly reactive intermediate, the so-called compound I (oxo-ferryl porphyrin pi-cation radical), which is generated via the reaction of peroxide with a ferric heme iron. However, the main reaction catalyzed by the heme-containing enzyme is determined by the accessibility of substrates to their active sites. Using the accumulated knowledge, we delineate a view, in which machineries of the heme-containing enzymes, especially the heme distal side structures, precisely regulate their functions in terms of sharing a common reactive intermediate. We also show the possibility that a hemoprotein of one functionality can be engineered to that with another functionality by modifying the heme distal side elements, on the basis of molecular-based mechanistic and structural data on these peroxide-utilizing enzymes.
Matsunaga
Isamu
I
Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA. imatsunaga@rics.bwh.haravard.edu
Shiro
Yoshitsugu
Y
D006420:Hemeproteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D015394:Molecular Structure; D010544:Peroxidases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D010545:Peroxides / Q000378:metabolism*; D015202:Protein Engineering
D006420:Hemeproteins; D010545:Peroxides; D010544:Peroxidases