CAS CH 273 Lecture Notes - Lecture 12: Peripheral Membrane Protein, Integral Membrane Protein, Lipid Bilayer
16 Dec 2015
School
Department
Course
Professor
Document Summary
O lipids can freely diffuse in the plane of the bilayer. Transverse diffusion (or flip- flop diffusion) is extremely slow (the half-times are days or more): the fluidity of the lipid bilayer is temperature-dependent. Lipid mobility and fluidity phospholipid to anchor to the membrane. 5. 4 rise per turn helix: so for 30 membrane, need 5. 4 /turn / 3. 6 aa/turn = 1. 5 rise/aa, thus 30 membrane/ 1. 5 /aa = 20 aa. After a short period, the two different dyes originated from the two different membranes will intermix: this has also be demonstrated by photobleaching experiments. Some proteins or lipids are specific for one of the two layers: glyco-groups face outside, lipids can be transferred to the other layers by one of the two different mechanisms, facilitated diffusion. A protein catalyzes the equilibrium of a phospholipid between the two layers. Eventually, the concentration at the two layers are the same. (flipase: active transport.
