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Flashcards in Regulation of Enzymes Deck (11):
1

In regards to synthesis and degradation, since Vmax = K3[Etotal], one way to increase or decrease activity is to increase or decrease ____

[Etotal]

2

By keeping enzymes, cofactors and substrates of two conflicting pathways physically separate, futile cycling of substrates is avoided. Give an example of this.

FA synthesis occurs in the cytosol
FA oxidation occurs in the mitochondria

3

Many hormones produce "second messengers" which are allosteric effectors of various enzymes and tissues. One popular second messenger that binds various enzymes, altering their activity is ___

cAMP

4

Some hormones increase the cytosolic ____, which interacts with a protein called calmodulin.

[Ca2+]

5

What happens to the Ca2+ - calmodulin complex?

affects the activity of a number of proteins

6

Phosphorylation is a type of ___ regulation

covalent

7

Phosphorylation is accomplished by a protein ___ which may be very specific for the enzyme or protein to be phosphorylated or may be broad in its specificity

kinase

8

Dephosphorylation is accomplished by a protein ____

phosphatase

9

In regards to proteolytic activation, some enzymes are synthesized in inactive form (zymogen or proenzyme). How are they activated?

proteolytic cleavage

10

What are some examples of digestive proteases (proteolytic enzymes)? Coagulation zymogens?

digestive proteases: trypsinogen, chymotripsinogen
coagulation zymogens: fibrinogen, prothrombin, etc

11

Name the three things that increase glycogen phosphorylase activity

1. allosteric effector AMP
2. phosphorylation of the enzyme
3. binding of Ca2+ - calmodulin