What is Coupled Phosphorylation?

[JamesU]

"Coupled Phosphorylation"

For school I am being forced to read SIlent Spring by Rachel Carson(which bores me to death, but anyways...) The author goes into very little detail on what coupled phosphorylation means, which is confuusing me every time she brings it up...Any helpon what this is...?

 

[jim mcnamara]

The book is 40+ years old, I believe what is referred to is the fact that phosphorylation of proteins (specifically enzymes) turns off the metabolic pathway they are active in - this is called a phosphorylation cascade.

The opposite effect, dephosphorylation, switches the enzymes activity back on - turning on the metabolic pathway.

Receptor sites on cell membranes respond to external hormones or hormone mimics like some chlorinated compounds either turning on a cascade or turning it off. glucagon and adrenaline turn on a p-cascade that shuts down glycolysis, for example.