CH 36 Reactive O2 species

arne1's version from 2015-09-25 16:03


Question Answer
H2O2 is scavanged by catalase (in peroxisomes - contains heme uses two H-peroxides as substrates) or glutationine peroxidase (selenium - needs reduced glutathionine; can also act on organic peroxides)
glutathionine peroxidase (needs 2GSH) can reverselippid peroxidation of unsaturated FAs in PM (important in RBCs)
Deficiency in superoxide dismutase leads toAmyotrophic lateral sclerosis (ALS) aka Lou Gherig's, often hereditary defect in dismutase gene
Functions of NOsmooth muscle relax, prevention of platelet aggregation, NT in brain
Chronic Granulomatous disease (CGD) hereditary NADPH oxidase deficiency. Recurrent infection by bacteria (pneumonia) or fungi (aspergillus). Less ROS and RNOS and HOCL. x linked
ALSsuperoxide dismutase deficiency. (Nerves are attacked)
Chronic granulomatous disease (CGD)NADPH oxidase deficiency. lack of formation in leukocytes which leads to less ROX, RNOS, HOCL. severe recurrent infections with fungi and pneumonia.
Myeloperoxidase deficiencylack of hypochlorous acid (HOCL) in phagolysosomes which is needed for destruction of fungi. Recurrant infections with candida albicans. Destruction of bacteria is normal!