Bio Lecture 5

Front 1

Kinetic Stability

Back 1

When an energy barrier prevents spontaneous reactions from occuring very fast, the reaction is kinetically stable

Front 2

Transition State

Back 2

Molecules that gain necessary activation energy occupy the transition state
Bonds are unstable and ready to be broken

Front 3

Peptidoglycan

Back 3

A combination of carbohydrate and protein
Major part of cell wall
Needs peptide linkages

Front 4

Transpeptidase

Back 4

The bacterial enzyme that links AA that are required to strengthen the peptidoglycan wall

Front 5

Chlamydomanos

Back 5

Green algae that needs to take in nitrogen
Does this by taking in nitrate or ammonia to synthesize AA

Front 6

Nitrate Reductase

Back 6

An enzyme that converts nitrate to ammonia

Front 7

Apoprotein

Back 7

Protein component without the prosthetic group

Front 8

Enzyme Ability

Back 8

Enzymes cannot change the sign of DELTA G
Can not convert an endergonic reaction into an exergonic reaction
To get an endergonic reaction to proceed, energy coupling is used

Front 9

3 Major Mechanisms of Enzymes

Back 9

1. Bring reacting molecules together
2. Expose the reactant molecule to altered charge environments that promote catalysis
3. Change the shape of the substrate molecule to mimic the transition state
*** Lowers required energy to get to transition state

Front 10

Enzyme Structure

Back 10

A protein that is functional in tertiary form
Lots of substrate, equilibrium shifts to the right
Not consumed, they are able to go back and mix with more substrates

Front 11

Enzymes and Loweing EA

Back 11

Allow substrate to occupy certain orientation
Provide a charge for substrate on active site
Provide conformation strain
Catalytic site of enzyme mimics transition state

Front 12

Induced Fit vs Lock and Key

Back 12

Lock and Key = enyme and substrate fit perfectly into each other
Induced fit: Enzyme changes shape upon substrate binding

Front 13

Km

Back 13

The amount of substrate needed to get 1/2 of maximum velocity
A measure of affinity - some enzymes have high Km, some have low
Higher in the presence of a competitive inhibitor

Front 14

Competitive Inhibitor

Back 14

Looks like the substrate and can bind to the active site
Competes for the active site

Front 15

Non-competitive Inhibition

Back 15

Specific molecules that inhibit enzyme activity but do not compete for the active site
They bind on a different location on the enzyme
This binding changes the shape of the enzyme, which reduces the ability of the enzyme to effectively bind to a substrate

Front 16

Vmax

Back 16

The max rate at which enzyme can trn over substrate
Measured at the saturating levels of substrate