Term
|
Definition
|
|
Term
|
Definition
| study of the rates of enzyme-catalyzed rxns |
|
|
Term
|
Definition
| quantity of reactant that disappears in a specified unit of time |
|
|
Term
| how to calculate velocity of a rxn (V) |
|
Definition
V = -d[A]/dt = d[P]/dt
V = velocity of rxn
d = decrease in substrate concxentration or increase in product concentration
t = time
A = reactant A
P = product P |
|
|
Term
| velocity of rxn (V) vs. rate constant (k) |
|
Definition
V = k[each reactant]
V = velocity of rxn
k = rate constant |
|
|
Term
|
Definition
| rxn in which the velocity is directly proportional to the reactant concentration
have unit s-1 |
|
|
Term
|
Definition
| rxn that includes 2 reactants
have units M-1 s-1 (per mole per second) |
|
|
Term
|
Definition
| second-order rxns that appear to be first-order rxns |
|
|
Term
|
Definition
| rxn in which rate is independent of rxn concentration |
|
|
Term
| rate equation of a first-order rxn |
|
Definition
|
|
Term
| rate equation of a second-order rxn |
|
Definition
|
|
Term
| this is a necessary intermediate in catalysis |
|
Definition
|
|
Term
| Michaelis-Menton equation |
|
Definition
| V0 = Vmax X ([S]/([S] + KM))
V0 = initial velocity
Vmak = maximum velocity
S = substrate
KM = Michaelis constant |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
| when Vmax can be obtained |
|
Definition
| when total enzyme (ET) is attained |
|
|
Term
| when the enzyme is said to be saturated |
|
Definition
| when all the available enzyme is bound to the substrate and displaying zero-order kinetics |
|
|
Term
|
Definition
| the substrate concentration at which the rxn velocity is half its maximal value |
|
|
Term
|
Definition
| 1/V0 = (KM/Vmax) X (1/S) + (1/Vmax) |
|
|
Term
| the KM value of an enzyme varies based on... |
|
Definition
| substrate and environmental conditions |
|
|
Term
| enzymes when substrate concentration is below KM |
|
Definition
| enzymes have little activity and are sensitive to changes in substrate concentration |
|
|
Term
| enzymes when substrate concentration is above KM |
|
Definition
| enzymes have much activity and are insensitive to changes in substrate concentration |
|
|
Term
| enzymes when substrate concentration is approximately KM |
|
Definition
| enzymes have much activity and are sensitive to changes in substrate concentration |
|
|
Term
| maximal velocity (Vmax) reveals... |
|
Definition
| an enzyme's turnover number |
|
|
Term
| an enzyme's turnover number |
|
Definition
| the number of substrate molecules than an enzyme can convert into product per unit time when the enzyme is fully saturated with substrate |
|
|
Term
| this limits theb rate of formation of the ES complex |
|
Definition
| diffusion; can't be faster than the diffusion controlled enzyme-substrate encounter |
|
|
Term
|
Definition
| when catalytic velocity is restricted only by the rate at which enzymes encounter substrate in the solution |
|
|
Term
| when enzymes have kinetic perfection |
|
Definition
| when they have their Kcat/KM ratios at their upper limits |
|
|
Term
| the 2 classes of multiple substrate rxns |
|
Definition
1: sequential rxns
2: double-displacement rxns |
|
|
Term
|
Definition
| all substrates must bind to the enzyme before any product is released |
|
|
Term
|
Definition
| rxn where a ternary complex forms |
|
|
Term
|
Definition
| consists of enzyme and both substrates |
|
|
Term
| the types of sequential mechanisms for sequential rxns |
|
Definition
|
|
Term
| ordered mechanism for sequential rxns |
|
Definition
| substrates bind to the enzyme in a defined sequence |
|
|
Term
| double-displacement (ping-pong) rxns |
|
Definition
| one or more products are released before all substrates bind the enzyme |
|
|
Term
| the defining feature of double-displacement rxns |
|
Definition
| the existence of a substituted enzyme intermediate |
|
|
Term
| substituted enzyme intermediate |
|
Definition
| in a double-displacement rxn, this is when the enzyme is temporarily modified |
|
|
Term
| representation of sequential rxn |
|
Definition
|
|
Term
| representation of double-displacement rxn |
|
Definition
|
|
Term
| which parameter of an enzyme-catalyzed rxn depends on enzyme concentration? |
|
Definition
|
|
Term
| KM is the equivalent of... |
|
Definition
| Substrate concentration when 1/2 Vmax is reached |
|
|
Term
| what parameter of an enzyme-catalyzed rxn is a measure for the affinity of its substrate? |
|
Definition
|
|
Term
| When a substrate concentration is MUCH greater than KM, the rate of catalysis is almost equal to... |
|
Definition
|
|
