Introduction Function catalyze conversion of pyruvate to acetyl-CoA net reaction pyruvate + NAD+ + CoA → acetyl-CoA + CO2 + NADH irreversible Structure 3 enzymes that require 5 cofactors thiamine pyrophosphate (B1) FAD (B2) NAD (B3) CoA (B5) lipoic acid similar to α-ketoglutarate dehydrogenase complex Regulation activators of pyruvate dehydrogenase ↓ in energy status of the cell ↑ NAD+/NADH ratio ↑ ADP ↑ exercise ↑ Ca2+ ↑ insulin inhibited by acetyl-CoA Clinical relevance pyruvate dehydrogenase deficiency pathophysiology X-linked (variable penetrance in females) accumulation of pyruvate alanine lactic acidosis pyruvate shunted to lactate to regenerate NAD+ presentation neurological defects treatment ↑ ketogenic nutrients lysine and leucine arsenic poisoning inhibits pyruvate dehydrogenase via inhibition of lipoic acid presentation vomiting rice water stools garlic breath
QUESTIONS 1 of 3 1 2 3 Previous Next Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK (M1.BC.14.34) A 64-year-old man who is post-op day 4 following a radical nephrectomy is noted to have a temperature of 103.4F, pulse of 115, blood pressure of 86/44, and respiratory rate of 26. Arterial blood gas shows a pH of 7.29 and pCO2 of 28. Chemistry panel shows: Na+ 136, Cl- 100, HCO3- 14. CBC is significant for a significant leukocytosis with bandemia. The laboratory reports that blood cultures are growing gram positive cocci.Which of the following is true about this patient's biochemical state? QID: 100099 Type & Select Correct Answer 1 Increased activity of alcohol dehydrogenase 8% (14/168) 2 Decreased activity of pyruvate dehydrogenase 55% (93/168) 3 Decreased activity of lactate dehydrogenase 15% (25/168) 4 Increased activity of isocitrate dehydrogenase 4% (6/168) 5 Increased flux through the electron transport chain 12% (20/168) M 1 Question Complexity D Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 2 Review Tested Concept Review Full Topic
All Videos (1) Login to View Community Videos Login to View Community Videos Pyruvate decarboxylation by pyruvate dehydrogenase Chris Robinson Biochemistry - Pyruvate Dehydrogenase Complex D 2/11/2015 211 views 5.0 (6) Biochemistry | Pyruvate Dehydrogenase Complex Biochemistry - Pyruvate Dehydrogenase Complex Listen Now 10:2 min 8/11/2022 22 plays 0.0 (0)