Enzyme Kinetics

Front 1

V= d[P] /dt is also what?

Back 1

V= -d[S]/dt

Front 2

With decreasing [S] and increasing [P] , what wil be lost with time of reaction?

Back 2

linearity, in some cases P may inhibit E at higher concentrations.

Front 3

All E in the form of ES is what?

Back 3

Saturated

Front 4

When saturation is at high [S] increasing the [S] doesn't do what?

Back 4

increase the rate of reaction any further

Front 5

The velocity obtained at saturating [S] is what?

Back 5

the maximum velocity (Vmax)

Front 6

What is Michaelis's constant?

Back 6

[S] is 1/2 the Vmax. The term is called the Km

Front 7

What units are Km expressed in?

Back 7

moles/liter or mg/ml

Front 8

V=Vmax[S]/[S]+Km is also what?

Back 8

Km=[S](Vmax-V)/V

so when, 2V=Vmax, Km=[S]

Front 9

Km is sometimes associated with what?

Back 9

the strength of binding of the substrate for the enzyme.

Front 10

A substance with low dissociation rate is what type of affinity?

Back 10

higher affinity

Front 11

A substrate with low dissociation rate (high affinity)for the enzyme would reach what?

Back 11

half-maximal velocity at lower [S]

Front 12

A turnover number of enzyme reactions is what?

Back 12

Kcat

Front 13

The larger the Kcat the more often what happens on the surface of the enzyme?

Back 13

catalytic events

Front 14

Units of Kcat are per what?
What does Kcat measure?

Back 14

per seconds, that is (s^-1)
measures number of substrate molecules turned over per enzyme per second. Values range from chymotypsin (0.1) to carbonic anhydrase (100,000).

Front 15

The Kcat/Km determines the efficency of the enzyme-mediated reaction by giving what?

Back 15

The percentage of the effective collisions.

Front 16

True or False
Some enzymes approach the theoretical limit where close to every collision result in catalysis.

Back 16

True.

Front 17

Cells far from the thermodynamic equilibrium are in what state?

Back 17

The steady state.

Front 18

A dead cell is at what?

Back 18

equilibrium