Enzymes III Flashcards
(38 cards)
what can you not distinguish irreversible inhibition from on a graph
non-competitive inhibotr
aspirin is an irreversible inhibotr of what
prostaglandin synthase
what does aspirine cause
covalent complex with reactive serine residue
serine gets acetylated
what is a suicide or trojan horse substrate
mask reactive compound until catalytic action of target enzyme activates
extreme specifity
COX-2
bad prostaglands, assocaited with inflammation of arthritis
COX -1
good prostaglands, protection of dGI mucosa
how is COX-2 differnt from COX-1
contains baline residue instead of isoleucine residue
how does parathion kill insect
irreversible inhibition of acetylcholine estrase
what does parthion form
stable phosphate ester with serine reside
how do you treat parathion position
atropine
isoenzymes
enzymes that have different amino acid sequences but catalyze the same biochemical rxn
what is the most abundant form of LDH normally
LDH2
LDH1 is mainly found where
heart and RBC
LDH5 is most commonly found where
liver and skeltal muscle
what LDHs are elevated following an MI
LDH1 and LDH2
what is incrased LDH5 diagnostic for
acute hepatitis
what do regulated enzymes often catalyze
slowest or rate limiting test or commited step
when do you have more PEPCK
when blood glucose is low
when do you have less PEPCK
when blood glucose is high
product inhibtion
enzyme is inhbited by products of reaction that it catalyzes
end protect inhibtion
the end product of a metabolic pathway inhibts an enzyme catalyzed step earlier in teh pathway
allosteric modulators
small molecules that regulate enzyme activity by binding at sites that are distinct from the acitive site
positive cooperativity
binding of substrate by active site in one subunit might allow substrate to bind more easily to the active sites of other subunits
what is the curve of allosteric enzymes
sigmoidal
