Table 7.2 Chemical components of microsomes
| Composition |
RNA, ribosomal and others |
Protein (variable), both enzymes and structural |
Lipids (30-50% of composition weight) Phospholipids Phosphatidylserine Cholesterol Lecithins Phosphatidyl inositol Unsaturated Fatty acids |
| Carbohydrate metabolism |
Glucose-6-phosphatase UDP-glucose dephosporylation L-ascorbic acid synthesis UDP-glycuronic acid metabolism |
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| Protein metabolism |
Several enzymes for protein synthesis Iodine incorporation enzymes Peptidases, amidases |
||
| Fatty acid metabolism |
Reductive synthesis of short chain fatty acids Acylation with Acyl-CoA (ligase) Synthesis of glycolipids and plasmalogens Neutral glyceride synthesis |
||
| Phospholipid metabolism |
Phosphatidic acid synthesis Decarboxylation of phosphatidylserine Redistribution of phosphatides in membranes Phosphatidylcholine synthesis Transmethylation of phosphatides |
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| Steroid metabolism |
Synthesis of cholesterol from acetate Interconversion and degradation of steroids Hydroxylations, aromatizations, dehydrogenases and hydroxylases |
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| Nucleotide metabolism |
Nucleoside diphosphatases NAD and NADH pyrophosphatase, NADase 5'-Nucleotidases |
||
| Oxidation-Reduction |
NADH and NADPH cytochrome C reductase Nonspecific and NADP diaphorase Pyridine nucleotides Cytochromes, P450, coenzyme Q |
||
| Transport and Transmission |
Sarcoplasmic AMPases Cholinesterase Mg++ Ca++ dependent AMPases |
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| Drug detoxication |
N- and O- deacylations N-demethylation, sidechain and thio-ester oxidation Desulphuration, deamination and deiodination Hydroxylation of azo dyes |
||
| Binding properties |
Azo dyes Iodide Epinephrine, norepinephrine |
Cell Biology Laboratory Manual