Proten Prufication Ewuations

Question 1

Specific activity

Answer 1

Total protein activity (U)/ total protein (mg)

Question 2

Purication level

Answer 2

Specific activity post/ specific activity of the crude

Question 3

Yield

Answer 3

Total protein activity post/ total activity crude

Question 4

Total activity

Answer 4

Unit/ml x volume of sample (ml)
Also known as a the enzymatic assay

Question 5

Total protein

Answer 5

Protein mg/ml x volume of sample ml
Aka the Bradford assay

Question 6

What is used to evaluate the effectiveness of a protein purification method

Answer 6

An assay

Question 7

What is SDS and what does it do

Answer 7

Is responsible for disturbing proteins and “coating them” in a uniform negative charge
- part of the denaturing process included breaking the disulphides bond

Question 8

What is affinity chromatography

Answer 8

The tendency for proteins to be attracted to certain molecules which bind to beads. The excess parties are removed and the target protein is eluted via high concentration solution

Question 9

What is metal affinity chromatography

Answer 9

The tendency for his tagged proteins to be attracted to a metal ion. The proteins bind to the metal and are eluted by a strong buffer or by lowering the pH

Question 10

What is salting out

Answer 10

The causation for proteins to pre top are out of solutions with a high concentration. This is because the positively charged salt ions outcompete the proteins ability to interact with water, causing them to Cluster together

Question 11

Size exclusion chromatography

Answer 11

Aka gel filtration chromatography
- the act of filtering proteins based on their molecular size. In a comlum with Prius beads allows small proteins to enter and take a longer path that larger proteins. Larger are extracted first