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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.

SUBMITTER: Matsui T

PROVIDER: S-EPMC3672231 | biostudies-literature | 2013 May

REPOSITORIES: biostudies-literature

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Heme degradation by Staphylococcus aureus IsdG and IsdI liberates formaldehyde rather than carbon monoxide.

Matsui Toshitaka T Nambu Shusuke S Ono Yukari Y Goulding Celia W CW Tsumoto Kouhei K Ikeda-Saito Masao M

Biochemistry 20130424 18

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 p ...[more]

PMID: 23600533

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Staphylococcus aureus IsdG and IsdI, heme-degrading enzymes with structural similarity to monooxygenases.

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