Main author: Norbert Bedő
Institution or Company: Chemistry Department, Faculty of Physical Sciences, Science Institute University of Iceland, Dunhagi 3, 107 Reykjavík
Co-Author, Institution or Company:
Sigríður G. Suman, Efnafræði/Chemistry Department Raunvísindastofnun HÍ/Science Institute, University of Iceland Dunhagi 3, 107 Reykjavik.
Introduction: Mammalian Cytochrome c Oxidase (CcO) is the terminal complex (complex IV) of the electron transfer chain. It catalyses the transfer of electrons from Ferrocytochrome c to molecular oxygen, converted later to water. Cyanide is a good ligand for most transition metal ions. It interacts with many metalloenzymes: Hemoglobin, cytochromes, and oxidases. Hemoglobin and CcO play critical roles in oxygen transport and ATP production, inhibition of these enzymes results in life-threatening situations.
Methods: Cyanide act as a non competitive inhibitor for CcO. Interactions of non-toxic molybdenum sulfur complexes and CcO are studied, also their influence on the cyanide inhibitory effects.
Results: In vivo studies showed that some of the complexes are non-toxic at concentrations that correspond to lethal cyanide concentration. Competitive in vitro studies of cyanide inhibited enzyme with the complexes and a possible reactivation of CcO activity are discussed.
Conclusion: After promising in vivo studies the complexes could be good candidates as an emergency treatment for cyanide poisoning. Reactivation of inhibited enzymatic activity may support the antidote application.