title: Heme degradation by Staphylococcus aureus IsdG and IsdI liberates formaldehyde rather than carbon monoxide.
abstract: IsdG and IsdI from Staphylococcus aureus are novel heme-degrading enzymes containing unusually nonplanar (ruffled) heme. While canonical heme-degrading enzymes, heme oxygenases, catalyze heme degradation coupled with the release of CO, in this study we demonstrate that the primary C1 product of the S. aureus enzymes is formaldehyde. This finding clearly reveals that both IsdG and IsdI degrade heme by an unusual mechanism distinct from the well-characterized heme oxygenase mechanism as recently proposed for MhuD from Mycobacterium tuberculosis. We conclude that heme ruffling is critical for the drastic mechanistic change for these novel bacterial enzymes.
authors.affiliation: Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira, Aoba, Sendai 980-8577, Japan.
authors.forename: Toshitaka
authors.initials: T
authors.lastname: Matsui
authors.forename: Shusuke
authors.initials: S
authors.lastname: Nambu
authors.forename: Yukari
authors.initials: Y
authors.lastname: Ono
authors.forename: Celia W
authors.initials: CW
authors.lastname: Goulding
authors.forename: Kouhei
authors.initials: K
authors.lastname: Tsumoto
authors.forename: Masao
authors.initials: M
authors.lastname: Ikeda-Saito
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism*; D002248:Carbon Monoxide / Q000378:metabolism*; D005557:Formaldehyde / Q000378:metabolism*; D006418:Heme / Q000378:metabolism*; D006868:Hydrolysis; D006899:Mixed Function Oxygenases / Q000378:metabolism*; D010105:Oxygenases / Q000378:metabolism*; D013211:Staphylococcus aureus / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D005557:Formaldehyde; D006418:Heme; D002248:Carbon Monoxide; C497164:IsdI protein, Staphylococcus aureus; D006899:Mixed Function Oxygenases; D010105:Oxygenases; C482079:IsdG protein, Staphylococcus aureus