Allosteric effect vs cooperativity

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LoLPoPs

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It seems like I'm getting confused between the two concepts:
allosteric effect vs cooperativity.

Both of them I thought were all or nothing where binding of one induces binding of others. And when it comes to question, both of them are almost always in the answer choices together.
Can someone clarify the two concepts please?
Thanks!!! :love:

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It seems like I'm getting confused between the two concepts:
allosteric effect vs cooperativity.

Both of them I thought were all or nothing where binding of one induces binding of others. And when it comes to question, both of them are almost always in the answer choices together.
Can someone clarify the two concepts please?
Thanks!!! :love:


allosteric: when an enzyme has more than one binding site (1 for substrate and 1 more) and binding of one molecule can change the enzyme so that the other site becomes active to be able to bind to another molecule. The second site can also change in shape so that the second molecule may not bind. so if the first molecule is an inhibitor then the second site will become deactivated and wont bind the substrate. If the 1st molecule is inducer then it may be needed to activate the second site so that the substrate can bind.


co-opeativity: this may or may not deal with enzyme conformations but it DEALS WITH AFFINITY. binding of 1 molecule increases the affinity for other molecules. This is positive co operativity. If the binding of one molecule decreases affinity for others it is negative cooperativity. This is particularly important in in vivo system where enzymes have to work with limited concentrations of substrates and there may be high concentrations of inhibitors present. Hemoglobin is one of these. When one oxygen binds it increases the affinity for other oxygens to bind. Usually this deals with multiple subunits interacting.

I hope that helps.
 
allosteric: when an enzyme has more than one binding site (1 for substrate and 1 more) and binding of one molecule can change the enzyme so that the other site becomes active to be able to bind to another molecule. The second site can also change in shape so that the second molecule may not bind. so if the first molecule is an inhibitor then the second site will become deactivated and wont bind the substrate. If the 1st molecule is inducer then it may be needed to activate the second site so that the substrate can bind.


co-opeativity: this may or may not deal with enzyme conformations but it DEALS WITH AFFINITY. binding of 1 molecule increases the affinity for other molecules. This is positive co operativity. If the binding of one molecule decreases affinity for others it is negative cooperativity. This is particularly important in in vivo system where enzymes have to work with limited concentrations of substrates and there may be high concentrations of inhibitors present. Hemoglobin is one of these. When one oxygen binds it increases the affinity for other oxygens to bind. Usually this deals with multiple subunits interacting.

I hope that helps.

Oh wow. This clarifies everything! Thanks a lot!!!!! :love:
 
allosteric: when an enzyme has more than one binding site (1 for substrate and 1 more) and binding of one molecule can change the enzyme so that the other site becomes active to be able to bind to another molecule. The second site can also change in shape so that the second molecule may not bind. so if the first molecule is an inhibitor then the second site will become deactivated and wont bind the substrate. If the 1st molecule is inducer then it may be needed to activate the second site so that the substrate can bind.


co-opeativity: this may or may not deal with enzyme conformations but it DEALS WITH AFFINITY. binding of 1 molecule increases the affinity for other molecules. This is positive co operativity. If the binding of one molecule decreases affinity for others it is negative cooperativity. This is particularly important in in vivo system where enzymes have to work with limited concentrations of substrates and there may be high concentrations of inhibitors present. Hemoglobin is one of these. When one oxygen binds it increases the affinity for other oxygens to bind. Usually this deals with multiple subunits interacting.

I hope that helps.

This is very helpful-but in regards to Allosteric: In Destroyer # 161, how come it says that "during allosteric interaction, when a molecule binds, a conformational change occurs and the primary binding site will NO LONGER bind to its usual substrate." Whereas above, it talks about it being able to do both.
 
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This is very helpful-but in regards to Allosteric: In Destroyer # 161, how come it says that "during allosteric interaction, when a molecule binds, a conformational change occurs and the primary binding site will NO LONGER bind to its usual substrate." Whereas above, it talks about it being able to do both.

There are two types of allosteric regulation

Positive allosteric regulation and negative allosteric regulation:

Positive allosteric regulation is where a molecule binds to OPEN the active site per se, hence "activating" the enzyme.

Negative allosteric regulation is where a molecule binds to CLOSE/INHIBIT the active site, hence "inhibiting" the enzyme.
 
There are two types of allosteric regulation

Positive allosteric regulation and negative allosteric regulation:

Positive allosteric regulation is where a molecule binds to OPEN the active site per se, hence "activating" the enzyme.

Negative allosteric regulation is where a molecule binds to CLOSE/INHIBIT the active site, hence "inhibiting" the enzyme.

That's what I thought..so I wonder why Destroyer implied otherwise. Thanks man.
 
That's what I thought..so I wonder why Destroyer implied otherwise. Thanks man.

As long as you understood it correctly, trust yourself. Some of the Destroyer and other practice questions baffled me quite a bit also. Be confident that you know it ;)
 
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