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Chương 3: TRAO ĐỔI CHẤT LIPID

3.1. Phân giải lipid

3.1.1 Sự thủy phân lipid

3.1.2 β-oxy hóa acid béo

3.2 Sinh tổng hợp lipid

3.2.1. Sinh tổng hợp acid béo

3.2.2 Sinh tổng hợp triacylglycerol

3.2.3 Sinh tổng hợp phospholipid

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Sơ đồ trao đổi chất lipid

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3.1.1.1. Sự thủy phân Triacylglycerol (dầu, mỡ trung tính) Sự thủy phân Triacylglycerol

3.1 Phân giải lipid

3.1.1 Sự thủy phân lipid

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3.1.1.2. Thủy phân Photpholipid

Photpholipase

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3.1.2 Sù chuyÓn ho¸ Glycerol

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3.1.3 Sự β – oxi hóa acid béo

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3.2. Sinh tæng hîp Triacylglycerol

3.2.1. Sinh tæng hîp acid bÐo (§ êng h íng Malonyl - CoA)

3.2.2. Sinh tæng hîp Triacylglycerol

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Phøc hîp Acid bÐo Synthase

• Acetyl-CoA-ACP Transacylase

• Malonyl-CoA-ACP Transacylase

• β-Ketoacyl-ACP Synthase

• β-Ketoacyl-ACP Reductase

• 3-Hydroxylacyl-ACP Dehydrogenase

• Enoyl-ACP Reductase

Phøc hîp gåm Protein vËn chuyÓn nhãm acyl (ACP) vµ 6 enzym:

3.2.1. Sinh tæng hîp acid bÐo

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Ph¶n øng tæng hîp Malonyl – CoA,

c¸c dÉn xuÊt Acetyl – ACP vµ Malonyl - ACP

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S¬ ®å ho¹t ®éng cña phøc hîp acid bÐo Synthase

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3.2.2. Sinh tæng hîp triacylglycerol

(§ êng h íng Kennedy)

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Sinh tæng hîp Axit Photphatidic

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Glycerol kinase is an important enzyme in glycerol metabolism. Glycerol is produced by breakdown of a fat. One pathway for metabolism of free glycerol depends on the phosphorylation of glycerol provided by glycerol kinase.Glycerol + ATP <=> Glycerol-3-Phosphate + ADP

Gly3PDH catalyzes the oxidation/reduction of glycerol-3-phosphate (Gly3P) and dihydroxyacetone phosphate (DHAP).DHAP + NADH + H+  <=> Glycerol-3-Phosphate + NAD+

Sinh tæng hîp Glycerol -3- photphat

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3.2.3 Sinh tæng hîp Photpholipid

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a. Sinh tæng hîp Phosphatidil-serin vµ Phosphatidil-ethanolamin

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• Sinh tæng hîp Phosphatidilcholin tõ Cholin

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• Sinh tæng hîp Phosphatidil-Ethanolamin

vµ Phosphatidil-Cholin

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b. Sinh tæng hîp Phosphatidil - serin

vµ phosphatidil - inositol

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Sinh tæng hîp Sfingolipid

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Sinh tæng hîp Phosphatidil - Inositol