What type of agar plate should I use?

[everarianas]

Hello,

I am thinking of conducting a science experiment to see the effects of the protein lysozyme on bacteria. I have found out that a bountiful amount of lysozyme in found in egg white, so I wanted to use the egg white as the source of the protein. I was searching the Internet to see how I could isolate the lysozyme from the egg white, and I came across a topic on Science Buddies where they were using gel electrophoresis with food coloring. I am aware that the electrophoresis can separate protein, so I was wondering if it would be possible to isolate the lysozyme from the egg white using the homemade gel electrophoresis? If it is possible, how would I do it? Would I actually put the egg white into the chamber and let it separate, or would I do something else? Also, if it worked, how would I wash, or separate the lysozyme from the gel so I could put the lysozyme on my bacteria petri dish?

Or, is it better to just put the egg white on my petri dishes instead of trying to isolate the lysozyme using the gel electrophoresis?

Here is the link to the project:
https://www.sciencebuddies.org/science- ... o&from=TSW

Thank you for your help

[donnahardy2]

Hi,

Egg white is composed of several different proteins, and lyzozyme is just one of the proteins. Wikipedia includes a list of all of the proteins:
http://en.wikipedia.org/wiki/Egg_white

Gel electrophoresis is an analytical technique and would not be suitable for purifying a quantity of the enzyme. Lysozyme is usually purified by chromatography techniques. This website includes a procedure using cation exchange chromatography, and the detailed procedure is included.

http://faculty.mansfield.edu/bganong/bi ... sozyme.htm

If you purified the lysozyme using chromatography, you could use the gel electrophoresis technique to determine the purity of the enzyme.

You can also purchase purified enzyme from commercial sources:

http://www.sigmaaldrich.com/catalog/Pro ... =ON&F=SPEC


It sounds like you are going to use the lysozyme for your experiment. This sounds like a fascinating project. If you used the whole egg white, you would be testing the effect of the mixture of proteins on the bacteria. It would be interesting to compare the difference between the mixture and the purified enzyme; this could be an independent variable for your project.

Please let us know if you need any more information.

Donna Hardy

[everarianas]

Thank you SO much for your response! It helped me greatly.

The link that you gave me about the cation exchange I have already looked at before. I have been considering using that technique, but the only problem is that some of what it is saying I don't understand (but I understand most of it), and I was also wondering if I could actually conduct the cation exchange at home. Do you think it is possible to conduct the experiment at home?

[everarianas]

I am doing an experiment on the effects of lysozyme on bacteria. I am not using a specific type of bacteria; I am taking samples from the inside of my mouth and fingertips to use as bacteria. I searched the Internet for agar plates, and I found all kinds and I am confused and don't know which ones to use. Here are some agar plates that I found on www.sciencestuff.com:
Nutrient Agar - http://www.sciencestuff.com/prod/L-p-Agar/1513-10
Trypticase Soy Agar w/ 5% Sheeps Blood - http://www.sciencestuff.com/prod/L-p-Agar/1516-10
Tryptic Soy Agar - http://www.sciencestuff.com/prod/L-p-Agar/1517-10
Potato Dextrose Agar - http://www.sciencestuff.com/prod/L-p-Agar/1522-10

Thank you for your help!

[everarianas]

Hello,
I am conducting an experiment where I test the effects of the protein lysozyme on bacteria. I am growing the bacteria on agar plates, and everwhere on the Internet it says to store the plates in an incubator.

How do you make a homemade incubator to store the bacteria plates?

THank you for you help!

[MaryB]

Hello,

Before you start your project, I just want to make sure you are aware of the risks of working with some bacteria. Please see the following link about “microorganism safety” before you continue and make sure you have appropriate supervision.

https://www.sciencebuddies.org/science- ... fety.shtml

Mary

[sunmoonstars]

Many bacteria will grow at room temperature, but often show faster growth if you can store them at body temperature (about 98 degrees F). If you have something that can keep them this temperature,that would be great, but if not, the plates at room temperature might grow well, too. If you want a home-made incubator, perhaps keeping the plates above/near your heater duct in the house or school will be able to give them a higher temperature.

The need for equipment is one reason we recommend that you work with a mentor who has equipment in their lab, if possible.

[sunmoonstars]

Hi,

The first link you provide will be suitable for your project.

Have fun!
Tonya

[MaryB]

In addition, here are a couple of links that may be helpful to you:

http://www.freesciencefairproject.com/b ... onies.html

http://www.umsl.edu/~microbes/pdf/Incubator.pdf

[donnahardy2]

Hi,

Cation exchange chromatography can be done at home, it's involves pouring buffers over a column and collecting the sample that elutes. However, you would need some way to prepare the buffers that are used to equilibrate the column and elute the lysozyme away from the other proteins. Do you have access to the buffer ingredients and a pH meter at school? Does your school have a UV monitor? Do you have access to a gel box and power supply so you can run gels to check the purity of the sample? Is there a cation exchange resin available? Don't worry if you don't; just let me know what resources you have available and I'll help figure out a way to get this done.

When is your project due?

Donna Hardy

[MelissaB]

Hi,

I have merged all of your topics so the experts can get a better idea of what you're doing and what you need help with. Please keep all future posts inside this one thread.

[deleted-71536]

Hi there,

The Science Buddies website has some very helpful information about agar: https://www.sciencebuddies.org/mentorin ... Agar.shtml

If you are trying to grow a variety of bacteria, I suggest using LB agar as your medium.

I hope that helps!

Heather