MrMistery wrote:An enzyme is a protein that has a specific three-dimensional shape. Without that shape, it cannot do whatever it is that it does. When placed at room temperature, all enzymes will slowly loose this three-dimensional shape. So in your hypothetical experiment, the enzyme will eventually get inactivated, though it would take a very long time for it. Exactly how long this would take would depend on the enzyme. An enzyme from a bacterium that normally functions at high temperature would take longer to misfold, but it would happen eventually.
Paralith wrote:I assume you meant, that increasing the enzyme concentration does not change the rate of reaction when all the substrate is used up /monopolized, correct? I'm sure there are plenty of enzyme active sites left if you keep adding more enzyme. :) .
Well it might depend on the thermodynamics. If you are investigating a reaction such hydrolysis then yes, you are correct, the two graphs would both look optimal (rise to reach a maximum and then decrease to 0). However, that will only go for reactions that are irreversible thermodynamically. If your reaction is actually reversible, then as the product accumulates it will begin to bind the enzyme and the reverse reaction will begin to occur.
There is no ideal temperature to retain conformation; basically the colder the better. That's why proteins always need to be kept on ice when working with them and they need to be stored at -80 degrees C.
What do you mean by "ideal for its conformation"? Thermal energy makes bonds in a protein constantly vibrate, the higher the temperature, the higher the vibration. Theferore, every once in a while, the protein will, by chance, "jump" to a conformation that it can't come back from. Thermostabile proteins are more stably folded, the vibration is more restricted, so the jump happens less often. There is no ideal temperature to retain conformation; basically the colder the better. That's why proteins always need to be kept on ice when working with them and they need to be stored at -80 degrees C.
Obviously in this case, the increased concentration of enzyme results in an increased rate of reaction, up to a given point when all of the active sites of the enzyme are used up.
However the question that occurred to me (and one not asked in the essay) is what would happen if you just kept adding more substrate
and simply replenished the substrate as it was used up?
In other words, would the enzymes continue to work indefinitely? Would they never stop working? And if they did stop working, at what point would this be and why?
jebus197 wrote:It's not entirely linked I suppose, but I'm also curious concerning how low temperatures affect the formation of peptide bonds in protein dehydration synthesis/condensation reaction? (And also it's mirror opposite, as in the hydrolysis/ reaction that occurs when the peptide chains of proteins break down?) Or in other words, what is the exact mechanism and effect of low temperatures on protein formation? (And while you're at it, if you feel up to it, could you please explain the process of decay under normal temperatures in reference to these reactions? Lol.)
In any case it's an oddity of life perhaps (although it appears to be a true statement) that nothing created by life processes (and nothing that the product of those processes in turn produce) is ever built to last. Everything that in any sense can be considered to be in any way engineered, appears always to have a definite start and an almost equally definite end. (With time alone probably being the only meaningful remaining variable). This seems to be equally as true of all biological processes, as it is for anything that we as humans might produce. (Which is quite a strange thought, lol).
This can be a separate topic in Biochemistry.
This can be a separate topic in Biology. Although, I think we've already discussed something similar before, regarding how life components are in fact required to be dynamic and short lived to allow for homeostasis. Try doing a search, and if nothing turns up, feel free to start a new thread on it.
jebus197 wrote:Thanks again. But this wasn't really a question, just an observation, that basically anything that is created by life is subject to fault and decay. (This includes not only biological process, but everything that is man made/engineered by humans too.) Is was an observation made in the context of enzymes and how even at very low temperatures they are unlikely to last indefinitely.
jebus197 wrote:Obviously in this case, the increased concentration of enzyme results in an increased rate of reaction, up to a given point when all of the active sites of the enzyme are used up.
jebus197 wrote:In other words, would the enzymes continue to work indefinitely? Would they never stop working? And if they did stop working, at what point would this be and why?
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