Non-enzymatic protein function Flashcards
Structural proteins
Compose the cytoskeleton, anchoring proteins, and parts of extracellular matrix, as well as connective tissue in the body.
Collagen, elastin, tubulin, actin, keratin.
Motor proteins
Capable of generating force and movement through conformational change.
Myosin, kinesin, dyenein.
Function: muscle contraction, vesicle movement w/in cells, cell motility.
Have catalytic activity: ATPases power movement.
Binding proteins
Bind to a specific substrate.
Function: hold substrate concentration at a steady state, sequester substrate in the body.
Cell adhesion molecules (CAM)
allow cells to bind to other cell surfaces.
How does electrophoresis based in isoelectric focusing isolate proteins?
The gel is a gradient of pHs, and the protein migrates to the area of the gel in which pH=pI.
pI is the pH at which the protein is neutral (a zwitterion.)
How does electrophoresis based in SDS-PAGE isolate proteins?
SDS-PAGE disrupts non-covalent interactions, (denaturing it) and bind to proteins, creating a net negative charge.
Proteins are then separated when an electric field is applied. Proteins move through the gel (towards the +) based on frictional coefficient, which is based on MASS.
What type of receptor(s) are hormones likely to act on?
f
What are the characteristics of immnoglobulins?
Two light chains, two heavy chains, held together with disulfide bridges.
Bind to one specific antigen.
Act via: 1) neutralizing antigen, making it unable to exert its effect. 2) Marking for destruction (opsonization.) 3) Clumping (agglutinating) antigen + antibody into large, insoluble protein complexes for phagocytosing.
How does a G-protein work?
f
Types of chromatography?
f
Why is UV spectroscopy a way to analyze protein concentration?
Aromatic side chains - work b/c ?
