regulation mechanisms Flashcards
what is homeostasis
maintenance of constant internal state of the body
what is metabolic flux
what does a lower [s] mean
more sensitive
what does a higher [s] mean
less sensitive
how to maintain a steady state in a reaction
all reactions in a pathway proceeds at the same net rate
why is AMP a more sensitive indicator of a cells energy state than ATP
a decrease in [ATP] greatly affects the activity ATP utilizing enzymes which leads to a dramatic increase in [AMP]
AMP production from ATP equations
ATP–>ADP+Pi
2ADP–>ATP+AMP
what does AMPK stand for
AMP-activated kinase
what does an increase in exercise or decrease in nutrients cause
increase in [AMP] and AMPK activity and glucose transport and glycolysis
decrease in fatty acid, cholesterol and protein synthesis
what are enzymes and what do they do
biocatalysts, accelerate biochemical reactions, operate under mild conditions, optimal conditions vary, remain unchanged after reaction, provides alternate pathway with lower Ea, free energy unchanged, equilibrium not affected
what regulates enzyme activity
substrate availability, conc of enzymes (balance between transcription and regulation), activity of enzymes (reversible allosteric interactions, reversible covalent modifications [de/phosphorylation]), availability of cofactors
what does protein kinase do
catalyse phosporylation
what does protein phosphatases do
catalyse dephosphorylation
where are proteins typically phosphorylated
hydroxyl group of serine/threonine/tyrosine
what are prosthetic groups
tightly bound coenzymes
