Metabolic energy and enzymatic activity Flashcards
ATP
adenosine triphosphate (contains adenine, a ribose sugar, and 3 phosphate groups)
ADP
adenosine diphosphate.
one phosphate group went away through hydrolysis
AMP
adenosine monophosphate.
2 phosphate group went away through the hydrolysis of ATP and then ADP
ATP work performance
1) driving endergonic reaction through phosphorylation of reactant
2) changing the shape and binding ability of proteins through phosphorylation
3) changing the shape and binding ability of proteins through non-covalent binding
endergonic
reaction that requires energy to be driven
exergonic
reaction that releases free energy from the process
ATP synthase
enzyme that promotes the endergonic reaction of ADP to ATP with a phosphate addition
in the inner layer of mitochondria, in the thylakoid membrane of chloroplast, in the plasma membrane of bacteria
enzymes
macromolecules acting as catalysts
substrate
the reactant that the enzyme acts on.
Every enzyme is extremely specific for its substrate
enzyme-substrate-complex
when an enzyme binds to a substrate
active site
the region of the enzyme where the substrate binds
induced fit
the enzyme changes its shape due to chemical reactions
cofactors
non-protein helpers for catalytic activity, bound tightly (inorganic as metals, non-reversible) or bound loosely (organic as vitamins, reversible)
apoenzyme
part of the enzyme that is not enzymatically active
holoenzyme
when an apoenzyme binds with a cofactor
inhibition
the action of enzyme inhibited,
reversible inhibition (weak interactions) irreversible inhibition (covalent bonds)
competitive inhibition
mimics the substrate, competing for the active site
noncompetitive inhibition
binds to the enzyme away from the active site changing the shape of the active site
allosteric regulation
Allosterically regulated enzymes are typically composed of several subunits, each with its active site.
The entire complex oscillates between an active and an inactive state
allosteric activator
regulatory molecules that bind to the enzyme in order to stabilize its active form
allosteric inhibitor
regulatory molecules that stabilize the inactive form of the enzyme
allosteric cooperativity
the active form is stabilized by the presence of a substrate in one of the active sites
feedback inhibition
the end-product of a metabolic pathway is used to regulate its own production
