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___ catalyze group-transfer
reactions.
Transferases
___ catalyze hydrolysis. Hydrolases
___ catalyze ligation or
joining of two substrates.
Ligases
___ catalyze lysis of a
substrate.
Lyases
___ catalyze oxidation-
reduction reactions.
Oxidoreductases
___ catalyze structural change
within a single molecule.
Isomerases
___ is an allosteric inhibitor of PFK-1
while ___ is an allosteric activator of
PFK-1.
PEP, ADP
___ is the affinity of the
substrate for the enzyme.
Km
___ is the slowest step and
the turnover number.
Kcat
___ is when there are no ways of intermediates and
everything takes place because the enzyme acts as one
complex without entering the bulk solvent.
Metabolite channeling
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A ___ is a coenzyme or metal ion that is
tightly or covalently bound to the enzyme.prosthetic group
A ___ is a complete active enzyme with
its bound coenzyme and/or metal ions.holoenzyme
A ___ is a compound that binds to an
enzyme and interferes with its activity.inhibitor
A ___ is the protein part of
the holoenzyme.
apoenzyme/apoprotein
A high Kcat would be consistent
with a ___ (fast, slow) reaction.fast
African sleeping sickness is
caused by ___.
Trypanosomes
Do allosteric enzymes exhibit
typical Michaelis-Menten kinetics?No
Do you want a high or low
Km?
Low
For the unimolecular reaction S -->
P, the rate equation is ___.V = k[S]
If there is no spermine or spermidine
then the cells cannot ___.divide
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In competitive inhibition the
Vmax ___ and Km ___.
stays the same, increases
In noncompetitive inhibition
the Vmax ___ and Km ___.
decreases, stays the same
In the absence of a substrate
the enzyme is in the ___ state.
T
In uncompetitive inhibition
the Vmax ___ and Km ___.
decreases, decreases
Irreversible inhibition is bound ___
while reversible inhibition is bound ___.covalently,
noncovalently
Is regulation by covalent modification
faster or slower than allosteric
regulation?
slower
Michaelis-Menten Kinetics is
a ___ or ___ order reaction.
zero, first
More substrate would create a
___ (faster, slower) reaction.
faster
Sigmoidal has ___ (one,
more than one) binding site.
more than one
Spermine and spermidine have ___
(negative, positive) charges.positive
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The ___ is the energy difference between
the ground state and the transition state.energy of activation
(Eact)
The ___ is the starting point for either
the forward or reverse reaction.ground state
The formation of E + P is the
___ step.
rate-limiting
Trypanosomes are ___ (eukaryotes,
prokaryotes) and ___ (multicellular,
unicellular).
eukaryotes, unicellular
Vo vs. [S] curve is ___
(hyperbolic, sigmoidal).
sigmoidal
When ES is kept at a constant
rate, it is called the ___ state.
steady
When ES is still being formed,
it is called the ___ state.
pre-steady
With an activator Km ___ and
with an inhibitor Km ___.
decreases, increases
