Lecture 5 Membrane Structure: Lipid Components Flashcards
What is Diaglycerol (DAG)
glycerol + two fatty acids
What is phosphatidic acid (PA)
DAG + phosphate
What is lysophosphatidic acid (LPA)
PA but missing one fatty acid
Phosphatidyl-ethanolamine (PE) and phosphatidyl-choline (PC) have what kind of charge?
They have a positive charged head but a net neutral composition
Phosphatidyl-serine (PS) has what kind of charge?
A neutral head but a net negative lipid
Why is phosphotidyl-inositol (PI) important?
it is important for signaling
What are plasmalogens
They are located in the heart and brain. They have one of the fatty acid chains attached differently
What is a sphingosine
a sphingolipid with one acyl chain
What is ceramide?
a sphingosine + one fatty acid
What is myelin
ceromide-phosphate -choline
What are cerebrosides and gangoliosides
glycosphingolipids
What is 3-cholesterol
It is not a phospholipid and it has a small head group
What are leaflets
2 layers
How is lateral mobility within a leaflet?
very good
What are flippases
A proteins that flips a lipid from one leaflet to another
Membrane fluidity organization: gel vs fluid
gel= well organized fluid= not organized
Membrane fluidity organization: short FA vs long FA (fatty acids)
shot FA move in fluid
long FA pack together
Describe sphingolipid movement
They are long FA and group together
Lipids rapids are ____ and contain _____ and _____
thick; sphingolipids and cholesterol
How is membrane curvature affected by lipids
hydrophobic/hydrophilic parts are different diameters
the two leaflets curve in opposite directions
Integral vs peripheral protein structure
Intergral proteins cannot be removed from the membrane
peripheral proteins can be removed from the membrane (removed by high amounts of salt/pH)
Transmembrane proteins (integral or peripheral?)
Always integral
What is a beta barrel
a round serias of beta sheets across a membrane
what is porin
A beta barrel protein that makes pores in bacterial membranes
What do PH domains bind?
phosphorylated PI’s (phosphotidyl-inositols)
