Term
| The main features of capdiolipin |
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Definition
- only eukaryotic lipid that is synthesized in the mitochondria
- found most prominently in the inner mitochondrial membrane of animals and plants where it constitutes 20% of the total lipid content (in plants also thylakoids)
- essential component of several complexes of the respiratory chain
- additional roles in apoptosis and other processes
- also found in the cell membrane of most bacteria; Archaea contain an analog of cardiolipin |
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Term
| What the archea lipids are based on? |
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Definition
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Term
| What determins charge of the lipid? |
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Definition
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Term
| What determines the length of lipid? |
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Definition
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Term
| Classification of lipids by charge |
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Definition
1) zwitterionic lipids - charge depends on the pH of the environment e.g. Phosphatidylcholine (PC), Phosphatidylethanolamine (PE) , in ph = 7 they tend to be negatively of neutrally charged.
2) Negatively charged lipids - negatively charged at physiological pH values e.g. Phoshatidylserine (PS) , Sulfoquinovosyldiacylglycerol (SQDG) . => Overall charge of membrane is negative, also does not allow two negatively charges aas to snorkel
3) Neutral lipids e.g. Monogalactosyldiacylglycerol (MGDG) , Digalactosyldiacylglycerol (DGDG), mainly in mitochondria. |
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Term
| How could fatty acids change their lenght? |
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Definition
Fatty acids could effectively increase their length with help of cholesterol, but this is not working for all fatty acids. |
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Term
| Classification of lipids by physical shape. Which of them can form a bilayer? |
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Definition
Cylindric: headgroup and hydrophobic part are approximately equal. This is bilayer lipids.
Cone/wedge: volumes of headgroup and hydrophobic part are different. Usually form micelles and determine the formation of bilayer. |
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Term
| Why do we need non bilayer lipids? |
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Definition
| To form curves in membranes, i.e. Goldgi apparatus |
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Term
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Definition
Combination of only cones and wedges like on this picture could not form a bilayer because of mismatch of hydrophobic part. |
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Term
| What is the formula for calculating packing parameter? What values correspond for cones, wedges and cylinders? |
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Definition
p = υ • a0^(-1) • lc^(-1), υ - effective volume of nonpolar region, a0 – optimal surface of the head group at minimal chemical potential, lc – length of hydrophobic part. If p< 0.5 – coneshaped → micelle, 0.5<p<1 cilinder → bilayer, p>1 wearge → inverted micelle. |
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Term
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Definition
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Term
| How unsaturation affects the packing desity of membrane? |
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Definition
| The higher unsaturation, the less density |
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Term
| What structure of the membrane is preffered by all organisms? |
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Definition
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Term
| Is the energy consumed in the bilayer-liquid state transition? |
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Definition
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Term
| How the increase in double bounds in fatty acids affect melting temperature? |
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Definition
| The bigger the number, the less the temperature |
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Term
| How the increase in C atoms number in fatty acids affect melting temperature? |
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Definition
| It increases the temperature |
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Term
| How sterols affect the physical and chemical preperties of bilayer? |
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Definition
1) reduce lateral mobility
2) reduce the fluidity and permeability
3) alter the length of the hydrophobic core. |
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