lab report 5

BioLab3 Lab Report 5
Enzymes

Student Name: Cooper Lyon

I. Enzyme Structure and Function

EXERCISE 1 – Preparation of an enzyme activity standard
At five minute intervals over the next fifteen minute period, record the color intensity of the solution of each test tube.
Time
(min)
Tube S1
Potato Extract + Catechol
Tube S2
Potato Extract + Water
Tube S3
Catechol + Water
0
Shade of Yellow
Clear/Milky
Clear/Milky
5
Shade of Yellow
Clear/Milky
Clear/Milky
10
Orange
Clear/Milky
Clear/Milky
15
Brown/Red
Clear/Milky
Clear/Milky

How can benzoquinone be detected?
Benzoquinone can be detected if you see a brownish amber color in the solution

Which two solutions need to be present to produce the brown-colored benzoquinone?
Potato extract and catechol need to be present

What substance is not present in tube S2 for the production of the brown-colored substance?
Catechol

What substance is not present in tube S3 for the production of the brown-colored substance?
Potato extract

II. Enzyme Specificity

EXERCISE 2 – Enzyme specificity

At five and ten minute intervals, record the color intensity in each test tube.
Time
(min)
Tube 1 with catechol
Tube 2 with hydroquinone
0
1
1
5
3
1
10
5
4

Based upon color intensity, to what degree does catechol oxidase react with hydroquinone?
4
What difference in chemical structure of the two substrates determines the specificity of catechol oxidase? The different location of the second -OH group

III. Temperature and Enzyme Activity

EXERCISE 3 – Enzyme activity and temperature

Record the relative color intensity at intervals of five and ten minutes.
Time
(min)
Tube 1
4oC
Tube 2
23oC
Tube 3
40oC
Tube 4
60oC
Tube 5
80oC
Tube 6
100oC
0
3
3
3
3
0
0
5
3
3
3
4
0
0
10
3
4
5
4
0
0

Double click the chart below. A spreadsheet will open. Enter the 10 minute read data into the spreadsheet in the areas provided. When you are finished, click into another area of the lab report. The spreadsheet will close automatically. Do not