title: Hydrogen sulfide activation in hemeproteins: the sulfheme scenario.
abstract: Traditionally known as a toxic gas, hydrogen sulfide (H2S) is now recognized as an important biological molecule involved in numerous physiological functions. Like nitric oxide (NO) and carbon monoxide (CO), H2S is produced endogenously in tissues and cells and can modulate biological processes by acting on target proteins. For example, interaction of H2S with the oxygenated form of human hemoglobin and myoglobin produces a sulfheme protein complex that has been implicated in H2S degradation. The presence of this sulfheme derivative has also been used as a marker for endogenous H2S synthesis and metabolism. Remarkably, human catalases and peroxidases also generate this sulfheme product. In this review, we describe the structural and functional aspects of the sulfheme derivative in these proteins and postulate a generalized mechanism for sulfheme protein formation. We also evaluate the possible physiological function of this complex and highlight the issues that remain to be assessed to determine the role of sulfheme proteins in H2S metabolism, detection and physiology.
authors: Department of Chemistry, University of Puerto Rico, Mayagüez Campus, PO Box 9019, Mayagüez 00681-9019, Puerto Rico.
authors: Bessie B
authors: BB
authors: Ríos-González
authors: Department of Chemistry, University of Puerto Rico, Mayagüez Campus, PO Box 9019, Mayagüez 00681-9019, Puerto Rico.
authors: Elddie M
authors: EM
authors: Román-Morales
authors: Department of Chemistry, University of Puerto Rico, Mayagüez Campus, PO Box 9019, Mayagüez 00681-9019, Puerto Rico.
authors: Ruth
authors: R
authors: Pietri
authors: Department of Chemistry, University of Puerto Rico, Mayagüez Campus, PO Box 9019, Mayagüez 00681-9019, Puerto Rico. Electronic address: juan.lopez16@upr.edu.
authors: Juan
authors: J
authors: López-Garriga
mesh_terms: D002248:Carbon Monoxide / Q000378:metabolism; D006418:Heme / Q000031:analogs & derivatives* / Q000096:biosynthesis / Q000378:metabolism; D006420:Hemeproteins / Q000378:metabolism*; D006801:Humans; D006862:Hydrogen Sulfide / Q000737:chemistry / Q000378:metabolism*; D009569:Nitric Oxide / Q000378:metabolism
chemical_list: D006420:Hemeproteins; C052173:sulfheme; D009569:Nitric Oxide; D006418:Heme; D002248:Carbon Monoxide; D006862:Hydrogen Sulfide
keywords: Ferryl intermediate; Histidine; Hydrogen sulfide; Sulfheme protein; Sulfhemoglobin; Sulfperoxidase