Metabolic Flux Flashcards
The allosteric modulation binds ___.
Noncovalently
Protein kinase is a ___ reaction.
Transferase reaction
Phosphoprotein phosphatase is a ___ reaction.
Hydrolysis reaction
Effectors that inhibit activity are termed?
Negative effectors
Effectors that increase enzyme activity are called?
Positive effectors
Is Glucose-6-phosphate a positive or negative effector?
Negative effector
Is glucose-6-phosphate a homotropic effect?
Yes; immediate substrate or product of the enzyme which serves as an allosteric effector.
is fructose 1,6-bisphosphate a positive or negative effector?
Positive
Is fructose 1,6-bisphosphate a heterotropic effector?
Yes; an allosteric effector who is neither the immediate substrate or product of the enzyme
ATP is a ______ effector.
Homotropic effector
Covalently modifiable enzymes will undergo the addition or removal of phosphate groups from specific ___, ___ or ___ residues of the enzyme.
Serine threonine or tyrosine
The majority of enzymes in any given cell are ___ allosterically or covalently modifiable.
Neither
HExokinase is inhibited by?
Glucose 6-phosphate
What inhibits PFK? (2)
ATP, Citrate
What activates PFK?
ADP, AMP, Fructose2,6-bisphosphate
What inhibits Pyruvate Kinase?
ATP
What Activates Pyruvate kinase?
Fuructose 1,6-bisphosphatate
Is Glucokinase inhibited by glucose 6-phosphate?
No!
Is pyruvate kinase covalently modifiable?
Yes!
Via the Law of Mass action, high concentrations of NADH and Acetyl CoA drive the E3 and E2 mechanisms____.
Backward
When E1 is phosphorylated, it is on or off?
Off
When E1 is dephosphorylated, it is on or off?
On
Pyruvate dehydrogenase phosphatase will turn on or off E1?
On
Acetyl-CoA and NADH will turn E1 on or off?
Off
Covalent regulations are under ___ control
Hormonal (Insulin, glucagon, epinephrine and norepinephrine)
Phosphodiesterase can quickly terminated what?
cAMP (2nd messenger)
The ___ messenger initiates an amplification cascase
First
Caffeine can inhibit ___.
Phosphodiesterase
Glycogen phosphorylase can be caused by what two hormones?
Glucagon(liver) and Epinephrine (muscle and liver)
When insuline is present, level of cAMP___.
Decrease
Transcription factors are?
Nuclear proteins, when activated bind to a DNA’s response element and activate or repress the transcription of that gene. Leading to increased or decreased synthesis of the encoded protein.
How long is the half-life of a protein?
Between 3 minutes and 20 hours
What is the half-life of insulin?
5-7 minutes
Ubituitination is a tag for what?
Destruction of defective protein. (Recycles garbage, makes amino acid)
