Jump to content

Defining "Inhibiting" and "Allosterically Regulating"


Recommended Posts

IIRC allosterically is an indirect method of regulation, e.g. tyrosine/serine/threonine phosphorylation as seen in most signalling pathways that require the activation or inactivation of a protein, that requires the modification of the target protein.

 

Inhibition mostly relates to the direct competitive inhibitors that compete with an enzymes substrate(s) in the active site thus preventing the enzyme from catalysing the reaction it would normally.

 

Hence allosteric inhibitors do it from behind, they don't actively compete for the active site.

Link to comment
Share on other sites

Almost, but not quite. Activation (or inhibition for that matter) by posttranslational modification are normally not considered to be allosteric regulation. Allosteric regulation is characterized by binding of a ligand at a specific site of the enzyme that is not the active site. Again, it does not refer to a modification of the enzyme itself.

 

Moreover, "inhibiting" refers to all means of inhibition (of which allosteric is but a subgroup) , what is meant in the OP is probably "competitive inhibition" vs. allosteric inhibition.

 

Note that allosteric regulation can be both activating as well as inhibiting. Competive modes of regulation are, per definitionem, always inhibitory.

Also I should add that the binding of the ligand to the allosteric site leads to confirmation changes resulting in activation/inactivation of the protein. Binding of a competitor blocks the active site, but does not necessarily result in larger confirmation changes.

Edited by CharonY
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.