Wade_hydrodynamicmethods Flashcards
what properties of macromolecules can hydrodynamic methods investigate
mass, conformation, shape and associations
two types of centrifugation preparations
equilibrium, sedimentation velocity
three types of electrophoresis
SDS page, isoelectric focusing, native PAGE
three types of chromatography
gel filtration, ion exchange and affinity
T/F. in a non-restrictive media, the molecule with the highest velocity will have the highest charge
True, although this is pretty much entirely theoretical
frictional drag coefficient is related to diffusion in what way?
they are inverse of each other, Friction = 1/Diffusion
what two forces oppose centrifugal force
buoyant forces and frictional drag
what property of molecules dominates sedimentation rates
molecular mass, then shape (high friction/drag of bulky elongated proteins slows velocity)
this centrifugation technique features high rotor speeds and short spin times
sedimentation velocity
how is sedimentation coefficient determined
you record sedimentation boundary position over time, then take the derivative of change in position over time
what is zonal sedimentation
sucrose gradient centrifugation, you have stable zones of variable density and particles sediment to match that density
this centrifugation technique features low rotor speeds and you can be spinning for days
equilibrium centrifugation
what does equilibrium centrifugation data measure
profiles of molecular distributions concentration as a function of distance
why are shape effects absent in SDS-PAGE gels?
proteins are denatured by SDS, so you only see size effects
what three properties of proteins determine mobility in native gels
charge, shape and size
