{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Lipid Metabolism II - Lipid Metabolism 2 Reading Gropper...

Info iconThis preview shows pages 1–14. Sign up to view the full content.

View Full Document Right Arrow Icon
Lipid Metabolism 2 Reading: Gropper 4 th ed, Ch 6, pp. 153–162 Gropper 5 th ed, Ch 5 pp. 159–168
Background image of page 1

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

View Full Document Right Arrow Icon
2 Objectives for today: Synthesis of fatty acids Synthesis of eicosanoids Metabolism of cholesterol
Background image of page 2
3
Background image of page 3

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

View Full Document Right Arrow Icon
4 Fatty Acid Synthesis Intro Except for linoleic acid and α -linolenic acid (and derivatives), body can make fatty acids from acetyl CoA Sequential assembly of a ‘starter’ molecule (Acetyl CoA) with malonyl CoA (derived from Acetyl CoA + CO 2 ) Two important reactions to remember: 1. Acetyl CoA carboxylase reaction Rate-limiting step Makes “starter” molecule 1. Fatty acid synthase system Elongates chain by 2 carbons 4-step process (repeated)
Background image of page 4
5 Acetyl CoA Translocation FA synthesized from acetyl CoA in the cytosol but almost all acetyl CoA is made in the mitochondrial matrix (by various pathways) Acetyl CoA cannot pass through inner mitochondrial membrane In the mitochondrion acetyl CoA is incorporated into citrate (Krebs cycle), which can move to cytosol In the cytosol citrate is converted into oxaloacetate and acetyl CoA (requires ATP)
Background image of page 5

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

View Full Document Right Arrow Icon
6 Fig. 4-15, p. 91
Background image of page 6
7 Reaction 1-Acetyl CoA Carboxylase Adds CO 2 to acetyl CoA to make malonyl CoA Complex enzyme; contains biotin Requires ATP Irreversible Commits acetyl CoA to fatty acid synthesis Rate-limiting step of fatty acid synthesis Inhibited by palmitoyl CoA (16:0 fatty acyl-CoA) Activated by citrate
Background image of page 7

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

View Full Document Right Arrow Icon
8 Reaction 2-FA Synthase Fatty acid synthase system Multi-enzyme complex Four-step process (repeated) Chain is elongated in 2-carbon (acetate) units Uses acetyl CoA and NADPH Process continues until palmitate (16:0)
Background image of page 8
9 Reaction 2-FA Synthase Fatty acid synthase system components Acyl carrier protein (ACP) Condensing enzyme (CE) Possess free -SH groups where ACoA and Malonyl CoA attach ACP “loaded” with acetyl CoA (loss of CoA) Acetyl group transferred to CE ACP then “loaded” with malonyl CoA (loss of CoA) Chain will build up on this part of the complex
Background image of page 9

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

View Full Document Right Arrow Icon
10 CONDENSATION CE CE
Background image of page 10
11 REDUCTION CE CE
Background image of page 11

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

View Full Document Right Arrow Icon
12 DEHYDRATION CE CE
Background image of page 12
13 REDUCTION CE CE
Background image of page 13

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

View Full Document Right Arrow Icon
Image of page 14
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}