Chapter_17

Chapter_17 - An overview of citric acid cycle • Gateway...

Info iconThis preview shows pages 1–10. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: An overview of citric acid cycle • Gateway to any aerobic metabolism of any molecules that can be converted to acetyl-CoA or dicarboxylic acid; • Important source of precursors for other biosynthesis, such as amino acids, nucleotide bases, cholesterol and porphyrin; • Acetyl group; • 2 CO2, 1 GTP; 8 e- in NADH or FADH2; oxaloacetate Glucose is completely oxidized through the citric acid cycle or the tricarboxylic acid (TCA) cycle or the Krebs cycle The formation of acetyl coA from pyruvate: the pyruvate dehydrogenase complex 4-10 md; The citric acid cycle oxidizes two-carbon units I. The formation of acetyl coA from pyruvate Three steps reactions; These steps must be coupled to preserve the free energy derived from the decarboxylation steps to drive the formation of NADH and acetyl-CoA. Pyruvate Dehydrogenase I. The formation of acetyl coA from pyruvate 1.1 Pyruvate combines with TPP and is then decarboxylated (E1) Exceptionally acidic Pyruvate dehydrogenase I. The formation of acetyl coA from pyruvate Step 2: the hydroxylethyl group attached to TPP is oxidized to form an acetyl group and concomitantly transferred to lipoamide (E1) Pyruvate dehydrogenase I. The formation of acetyl coA from pyruvate Step 3 The acetyl group is transferred from acetyllipoamide to CoA to form acetyl CoA(E2) Dihydrolipoyl transacetylase E3 modifies redox potential of FAD The citric acid cycle oxidizes two-carbon units Flexible linkages allow lipoamide to move between different active sites E2--trimer; E1-- α 2 β 2 tetramer; E3-- αβ dimer Pyruvate dehydrogenase Flexible linkages allow lipoamide to move between different active sites E2--trimer; E1-- α 2 β 2 tetramer; E3-- αβ dimer Pyruvate dehydrogenase...
View Full Document

This note was uploaded on 09/13/2010 for the course BIOL 4087 taught by Professor Waldrop during the Spring '08 term at LSU.

Page1 / 26

Chapter_17 - An overview of citric acid cycle • Gateway...

This preview shows document pages 1 - 10. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online