Reactions and regulation of mitochondrial sulfur catabolism

• Applicant: Professorin Dr. Tatjana Hildebrandt
• Subject Area: Biochemistry
• Term: from 2009 to 2013
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 130252757

Hydrogen sulfide (H2S) is highly toxic, but it also has physiological functions as a signalling molecule and as a substrate for mitochondrial ATP production. Animal mitochondria oxidize sulfide to thiosulfate in three consecutive steps. Genetic defects in the second enzyme of this pathway, a sulfur dioxygenase, cause the fatal metabolic disorder ethylmalonic encephalopathy. The project presented here aims to characterize the individual reaction steps of sulfide oxidation to sulfate and to identify side reactions of this pathway. In particular, the reaction mechanism of the sulfur dioxygenase and its general role in metabolism will be studied. Additionally, research will focus on a regulatory mechanism that protects mitochondria from sulfide inhibition, thus allowing an effective handling of the toxic compound.

• DFG Programme: Research Grants