Can Cellulase Proteins Be Integrated into Human Gut Bacteria for Digestion?

[MonsieurWise]

Hi, I'm currently planning on a project for my school's science fair. I was thinking about the cellulase proteins topic, because I thought it would be interesting if humans can digest cellulose just like herbivores...

I found out that breaking down cellulose requires many steps, thus demands a list of different kind of enzymes, not only one kind as I initially thought. So I have a few questions and I need some advices ^^'.

Where can I find a full list of bacteria and enzymes that involve in cellulolysis in cows? I tried to search but all they have was some general info...

After that, I would like to find out if one can somehow integrate the cellulase-producing-bacteria's genes to that of a bacteria that lives in human's stomach, the E.Coli for example, so human would have a continuous source of cellulase. Is that actually possible? If it is, what method should I use? And would it be possible to do it in a high school's lab in about 30 days?

Thank you so much in advance .

 

[FairtuMydling]

Hi, I'm currently planning on a project for my school's science fair. I was thinking about the cellulase proteins topic, because I thought it would be interesting if humans can digest cellulose just like herbivores...

I found out that breaking down cellulose requires many steps, thus demands a list of different kind of enzymes, not only one kind as I initially thought. So I have a few questions and I need some advices ^^'.

Where can I find a full list of bacteria and enzymes that involve in cellulolysis in cows? I tried to search but all they have was some general info...

This is not a full list but it is just about all we know at the moment. There are 115 families of different cellulases (or glycoside hydrolases - GH for short). You will see that there are many hundreds that have been discovered.

http://www.cazy.org/Glycoside-Hydrolases.html

After that, I would like to find out if one can somehow integrate the cellulase-producing-bacteria's genes to that of a bacteria that lives in human's stomach, the E.Coli for example, so human would have a continuous source of cellulase. Is that actually possible? If it is, what method should I use? And would it be possible to do it in a high school's lab in about 30 days?

Thank you so much in advance .

It IS possible to engineer E. coli to express cellulases, however you will need a PhD in Molecular Biology and a fully equipped PC2 laboratory. You won't be able to do it at school...and it takes longer than 30 days generally, unless you are repeating someone else's work, but even then you have to order the gene and that can take several weeks to get to you and that is before you even start the lab work.

You can get a commercial cellulase enzyme mixture from Novozymes (called the Novozymes Biomass Kit - call them up). It contains the four basic enzymes you need to hydrolyse cellulose to glucoses. You might be able to get your teacher to get some then you can do experiments on biomass or newspaper or cotton and test to see how fast the sugars are produced. It is not very exciting to watch though as it takes at least overnight. Have a chat to your teacher about it...

Cheers and good luck,

FM

 

[MonsieurWise]

Wow . I never thought it would be so complicated... I initially thought that transferring the genes would be almost like the "glowing bacteria" experiment my friend is doing...
Thank you so much for the info . It helps a lot!
Thanks again ^^.

 

[Monique]

It IS possible to engineer E. coli to express cellulases, however you will need a PhD in Molecular Biology and a fully equipped PC2 laboratory. You won't be able to do it at school...and it takes longer than 30 days generally, unless you are repeating someone else's work, but even then you have to order the gene and that can take several weeks to get to you and that is before you even start the lab work.

I don't fully agree there. A bachelor student should be able to do it in one-two weeks. Isolate cDNA of the required gene, put it into an expression vector, transform the bacteria and voila (not taking into account Murphy's law). I agree that it is not a project for a high-school student.

 

[MonsieurWise]

I have one more question...I bought the cellulase (expensive!) and I'm trying to break down the cellulose outside the body. Several things I want to ask: Will cellulases get used up in the body? If it does, will cellulases be used up in the outside environment? Will they just change their shapes, do the work, and then return to initial state? And after the cellulase break down the cellulose in a petri disk, is there a particular method for me to separate the glucose from the mess of enzymes, cellulose and any other products in the middle of breaking down?
I know that's a lot of questions...
Thank you so much in advance!