JCE Software Chemistry Comes Alive!
Different Amounts of Substrate

Increasing the amount of substrate in an enzymatic reaction increases the amount of product produced.

View slide thumbnails.
View Slide Thumbnails
  Next movie.
View Next Movie
 

2.4 MB, 42 seconds

File: MOVIES/KJBIOCHEM/GLUOXID1.MOV

Voiceover
The enzyme glucose oxidase, is poured into two beakers containing buffer, horseradish peroxidase and a dye. Different concentrations of glucose are added to the two beakers. Glucose oxidase catalyzes the formation of gluconolactone from glucose. At the same time, the dye is converted to a colored compound. The formation of the blue-green color is used to follow the course of the reaction. The beaker with more glucose is a darker color, indicating that more gluconolactone was produced.

Discussion
Glucose oxidase catalyzes the formation of gluconolactone from glucose and also forms hydrogen peroxide as a by-product of the reaction. The horseradish peroxidase breaks down hydrogen peroxide into water and oxygen, using the dye as an electron donor. At the same time, the dye is converted to its oxidized form, which is a colored compound. Since the amount of hydrogen peroxide produced indicates how much reaction has taken place, the formation of the blue-green color can be used to follow the course of the reaction.


Design, Text, and Demonstration:  
  Kristin Johnson University of Wisconsin - Madison, Madison, WI 53706
Video production, editing, and voice:  
  Jerrold J. Jacobsen University of Wisconsin - Madison, Madison, WI 53706
  Greg Minix University of Wisconsin - Madison, College of Engineering, Madison, WI 53706
  Michael Killips University of Wisconsin - Madison, School of Nursing, Madison, WI 53706