7 Flashcards
what sites exist for an allosteric enzyme
active and regulatory
do allosteric enzymes obey michaelis-menten kinetics
no
what kind of activity curves are found for
sigmoidal
what is homotropy/homoallosrery
substrates are effectors
may bind active sites or regulatory sitres
do allosteric enzymes have quaternary structure
many of them yes
describe ATCase
6 catalytic subinits and 6 regulatory
D3 symmetry
first step in CTP biosynthesis
activated by ATP
feedback inhibition
what are feedback inhibitors usually
allosteric modulators
describe the following as homo/hetero inhibitoris/ activatros for ATc
CTP
ATP
aspratate
CTP heterotropic inhibitor
ATP heterotropic activator
asparate homotropic activator
describe the shape of phosphofructokinase
d6 HOMOTETRAMER
describe ATP relationship to phosphofructokinase
homotropic inhibitor
2 binding sites (active and regulatory)
describe fructose-6-phosphate relationship to phosphofructokinase
binds to active site
homotropic activatro
describe AMP relationship to phosphofructokinase
heterotopic(+)
describe phosphoenolpyruvate relationship
heterotropic (-)
what kind of change is reversible covalent modification associated with
tertriary structure change
is glycogen synthase anabolic or catabolic
anabolic
how is glycogen phosphorylase reglated
phosphorylation
what are phosphrylation sites on glycogen synthase associated with
reducation in actvity
is phosphorylate isocitrate dehydrogenase active or inactive
inactive
why is phosphorylated isocitrate dehygenase inactiver
phopshate takes same spot as substrate
