4.4 Cofactors, coenzymes, and prosthetic groups Flashcards
what’s a cofactor
a non-protein ‘helper’ to the enzyme it may form part of the active site or transfer an atom or group of atoms from one reaction to another
when are inorganic cofactors obtained from
via the diet as minerals
what inorganic cofactor does amylase need to for the correct shaped active site to break starch down
Cl- ion
what’s a coenzyme
an organic cofactor a helper to the enzyme
where are coenzyme derived from
derived from vitamins in the diet
what coenzyme does vitamin B3 synthesis and what does this coenzyme do
it synthesises NAD a coenzyme responsible for the transfer of H atoms between molecules involved in respiration NADP also has a similar role
what coenzyme does vitamin B5 make and what does this coenzyme do
it makes coenzyme A which breaks down fatty acids and carbs in respiration
what are prosthetic groups
they are cofactors which are tightly bound to the enzyme protein and form a permanent feature
which is the prosthetic group for carbonic anhydride
zinc ions Zn2+ for part of the structure for carbonic anhydrase and this enzyme is nessacary for the metabolism of CO2
why are some enzymes produced in an inactive form
they could cause damage to the cell producing the or the tissues where they are release
what is precursor activation
when an enzyme produced in an inactive form undergoes an change in shape usually to the active site to be activated, this can happen by adding a cofactor
what’s a precursor enzyme called
apoenzyme
what’s a precursor enzyme called once the cofactor has been added
holoenzyme
what could trigger the activation of an inactive enzyme and what an example of this
a change in temp or pH eg pepsinogen is activated by the acidic pH in the stomach to transfer to pepsin
