Science Buddies: "Ask an Expert"

This is a chemistry/biochemistry question. I've already done some research and figured out this:

First, it kills bacteria by dissolving the lipids in the cell membrane. Now that the cell membrane is more water soluble, the alcohol is able to enter the bacterium and denature its proteins. The proteins change shape and lose their biological function. Without functioning proteins, the bacteria will die.

But after thinking about it, I realize that there are no chemistry concepts in that. I am in charge of the chemistry research. It does relate to structures of proteins. According to the biochemistry option in my chemistry book, proteins of quaternary structure denature in this situation.
Does all this apply to bacteria in the mouth/on the tongue as well? Or do the proteins of oral bacteria have a primary, secondary, or tertiary structure?

And if you have any additional information on how phenols and alcohols work on oral bacteria, please reply! Thank you for reading and thanks for the help in advance.

Hello,

There are several different species of bacteria that live in your mouth – all of them have proteins. Every protein has a primary structure, this is the amino acid sequence of the protein. Depending on what this sequence is, proteins can then fold to form secondary structures (e.g. α-helix or β-sheet). The tertiary structure of a protein is the 3D form, i.e. what the overall protein shape is. See the following link for a more thorough explanation:

http://themedicalbiochemistrypage.org/p ... cture.html
http://en.wikipedia.org/wiki/Protein_structure

Here are a couple of links that explain how alcohols denature proteins:

http://www.elmhurst.edu/~chm/vchembook/ ... ation.html
http://pirate.shu.edu/~rawncarr/Denaturation.doc

I hope this information is helpful. Let me know if you have any further questions.

Mary

Wow, Mary. These sites are amazing. They explain the structures much better than my book. Thank you very much! The sites are going to be very useful in my project and in the future for studying!

Happy to help. Please let us know if you have any further questions.

Mary