L11 Flashcards
what does an uncompetitive inhibitor do to an enzyme
binds the ES and stops transition to EP
what part of the enzyme can you speed up
the amount of time it takes to find the substrate, but not the other time it takes to make the products
competitive Vmax and Km
Vmax same
Km higher
non-competitive inhibitor Vmax and Km
Vmax lower
Km same
uncompetitive inhibitor Vmax and Km
Vmax lower
Km lower
what is the concentration of an enzyme called
activity
what are the units of activity
U/ml or U/ul
when you multiply activity by volume of enzyme, what is that
total activity
whats the potency of an enzyme or weight of protein called
specific activity
what are the units of specific activity
U/mg
activity/ protein concentration
how to calculate specific activity
units of enzyme / amount of protein
how to calculate enzyme activity
units of enzyme / volume
how to calculate total activity
activity x volume
when specific activity goes up, what does that indicate?
that we have purified our enzyme away from other proteins
when activity goes up, what does that mean
just that the concentration went up, doesn’t really tell us if we’ve purified
what enzymes are used for protein extraction
cytoplasmic enzymes
what enzymes break down proteins
proteolysis
what should be done to make sure no enzymes or proteins die once extracted from the cell (3)
ph changes
heat denaturation
oxidation
assays should be: (4)
sensitive
specific
rapid
quantitative
what kind of purification is electrophoresis
charge
what kind of purification is gel electrophoresis
size
what must the protein be in order for it to be centrifuged
soluble
what is the supernatant
the protein at the top of the centrifuge tube
whats a common and reversible purification method
salting out
what kind of purification is salting out
solubility
what is dialysis
de salting
what is dialysis good for? bad for?
great for separating proteins from salts
bad for separating proteins based on size
what is chromatography
techniques to separate mixtures based on physical properties such as size or charge
whats the stationary phase
a substance that the compounds to be separated pass by or interact with
whats the mobile phase
the carrier for the compounds to be separated
5 steps to column chromatography
pouring
packing
loading
running/eluting
collecting
what makes up stationary phase in size exclusion chromatography
porous beads
whats the volume of the column
Vt
volume outside the beads
Vo
volume inside the beads
Vi
volume at which sample is eluted
Ve
partition coefficient
fraction of the pores within the beads available to the sample
if Kav is 1, what does that mean
beads are fully accessible
if Kav is 0, what does that mean
always excluded by beads
what will be the fastest traveller
Vo
