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29 Cards in this Set
- Front
- Back
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What are the three functions of PPP?
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Generation of NADPH for reductive biosynthetic reactions
Generation of ribose-5-phosphate for nucleotide biosynthesis Interconversions of dietary carbohydrates into glycolytic/gluconeogenic intermediates |
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What function of the immune system utilizes PPP heavily?
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Phagocytic killing cells use NADPH for oxidative bursts
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What is an oxidative burst?
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when cells release reactive oxygen species to degrade bacteria or internalized particles in a cell
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Which reduced electron carrier is most prominently used in reductive biosynthetic reactions?
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NADPH (rather than NADH)
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Why is PPP important for rapidly-dividing cells?
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PPP generates ribose-5-phosphate, the backbone of DNA. Quickly dividing cells need to be able to reproduce large amounts of DNA
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In what tissues is PPP most prominent?
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Liver
Adipose tissue Adrenal cortex Thyroid Erythrocytes Testis Lactating mammary gland Phagocytic cells |
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Which enzyme in the pentose phosphate pathway is the regulating enzyme?
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Glucose-6-Phosphate Dehydrogenase
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How many enzymes in PPP generate NADPH?
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2 (These are the major source of NADPH)
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Where does all reductive biosynthesis occur?
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In the cytosol
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Where does most oxidation chemistry occur?
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In the mitochondria
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Which oxidation step doesn't occur in the mitochondria?
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Glucose -> G6P
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What are the primary needs for NADPH?
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Reductive biosynthetic reactions (transferring electrons from smaller molecules to use energy to make larger molecules)
Control of oxidative stress |
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What purpose does glutathione serve in oxidative stress management?
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It reduces reactive oxygen species & lipid peroxidation intermediates
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What happens to glutathione when it reduces reactive oxygen species?
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two molecules of glutathione form a disulfide bond
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What enzyme splits the oxidized glutathione dimer?
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Glutathione reductase
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What enzyme oxidizes the glutathione monomers while reducing reactive oxygen species?
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Glutathione peroxidase
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What cofactor does glutathione peroxidase require?
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Selenium (This is one of the few enzymes which actually uses this cofactor)
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What is the most common enzyme deficiency worldwide?
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G6PDH Deficiency
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Why does the mutation survive?
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The weaker cells don't support the malarial plasmodium's life cycle
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what are the common symptoms of G6PDH deficiency?
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neonatal jaundice
acute hemolytic anemia |
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What is the enzyme complex called which produces oxygen radicals?
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NADPH oxidase
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What is chronic granulomatous disease?
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Defective NADPH oxidase complex in phagocytic cells
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What is the NADPH oxidase complex used for?
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produce oxygen radicals to phagocytize microorganisms
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What are the symptoms of Chromic Granulomatous Disease (CGD)?
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Pneumonia, skin abscesses, tissue abscesses, and organ abscesses, suppurative arthritis, osteomyelitis, recurrent infections
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What is suppurative arthritis?
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Infectious arthritis - caused by a bacterial infection of the joints
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What is osteomyelitis?
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inflammation-induced destruction of bone
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What deficiency also manifests with similar symptoms to CGD?
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G6PDH deficiency
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What are the 4 take-home points of PPP?
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Makes NADPH
Makes Ribose-5-Phosphate Defect leads to Anemia Defect could lead to CGD |
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what can trigger dangerous hemolytic anemia in patients with G6PDH deficiency?
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infections
fava beans quinine (in antimalarials and tonic water) sulfonamides sulfones |
