Question

what are the digestive enzymes that cells contain?

Answer 1

There's a pretty large number, depending on how you define "digestive." There are a few major classes though that are good to be aware of.

The digestive enzymes you're probably referring to are the acid hydrolases in lysosomes. These are enzymes that degrade various waste macromolecules (proteins, lipids, etc) into their component parts in the acidic environment of the lysosome in order to be exocytosed or used to rebuild new macromolecules.

Another important enzyme you could say is digestive is the proteasome, a large protein complex responsible for breaking down intracellular enzymes if misfolded or after their functional "lifetime" is over. Again, the amino acids retrieved can be reused by the cell to make new proteins.

If you really want to stretch what is defined as a digestive enzyme, a third class would be the nucleases. These are enzymes that break down nucleic acids such as DNA and RNA into their component nucleotides. While they are used to degrade DNA and RNA in cells, they are involved in many other processes too that aren't strictly degradative, such as DNA repair or somatic recombination in immune cells.

As with all things relating to molecular biology, this really only scratches the surface...hopefully that helps!

Answer 2

so based on that question "if digestive enzymes can destroy DNA, why would we have them in our cells? and Why don't they regularly destroy your DNA?"

Answer 3

Great question! As it turns out, these enzymes are very highly regulated for exactly that reason - the last thing you want is for your cell to starting digesting its own DNA. For example, some nucleases are only produced under special circumstances in response to specific signals. Other nucleases have a very low affinity for DNA to begin with, and are only able to interact with it in the presence of other proteins, which themselves may only be produced under certain circumstances,

Answer 4

While I'm at it...some nucleases involved in DNA repair only recognize specific sequences or nucleotides. For example, you probably know that uracil is not normally found in DNA. If a polymerase accidentally incorporates one into it (or a thymine residue is demethylated), a nuclease will recognize it out of context and remove it.

Answer 5

so the digestive enzymes help to repair the DNA strand? is that why we have them in our cells?

Answer 6

Yes, that's one of the functions of nucleases. The other digestive enzymes serve other functions as I outlined above.

Answer 7

these questions are based on an extraction of DNA lab, so would i answer that "the digestive enzymes in the cell is the acid hydrolases in lysosomes which help to degrade the waste macromolecules and then break them down into smaller molecules to help re build other molecules, which then will lead to the damage of the cell membrane which will then lead to the destruction of the DNA molecules and at the same time when it destroys the DNA molecules it helps to repair the DNA strand. ?

Answer 8

You got the first part of your answer, but I'm not sure where the "damaging the cell membrane" bit is coming from...acid hydrolases and nucleases are two very different kinds of enzymes that perform similar functions on different macromolecules, and they're involved in different processes.

Answer 9

well then how do the digestive enzymes get to the DNA strand?

Answer 10

The nucleases are in the nucleus. The acid hydrolases are in the lysosomes. Two different kinds of digestive enzymes in two different compartments.

Answer 11

ohh ok, so there are different digestive enzymes in different parts of the cell right?? If so, then do digestive enzymes of the cell have anything to do with the digestive enzymes that can destroy the DNA??

Answer 12

When you say "digestive enzymes of the cell," are you talking about the acid hydrolases? They have nothing to do with destroying the DNA. Nucleases are also digestive enzymes of the cell...

Answer 13

well, the question on my page says "What digestive enzymes do cells contain? If digestive enzymes can destroy DNA, why do we have them in our cells? Why don't they regularly destroy our DNA?" and if it helps in any way, this is a lab based on a DNA extraction lab using Gatorade and isotropy alcohol.

Answer 14

Well I answered all those questions. First I gave several examples of digestive enzymes, which is probably what your first question is looking for. The rest of the questions deal specifically with the digestive enzymes that degrade DNA, the nucleases, which is what I spoke about later.

Answer 15

Since this is a lab, your textbook/notes/introduction to the lab in your lab manual might have additional relevant information.

Answer 16

I wish that's so, but sometimes out teacher wants us to go beyond what we are actually working on i guess to prepare us for university... thank for your help, ill look over what you said again and ill see what i can put together, thank you :)

Answer 17

Np good luck!

Answer 18

thanx :D