lecture 9 Flashcards
how can enzymes catalyse thermodyanically viable reactions
by lowering the activation energy of the reaction
when an enzyme catalyses a reaction what doesn’t change
the delta G value of the overall reaction doesn’t change
what are the 6 classes of enzyme
oxidoreductases, transferases, hydrolases, lyases, isomerases, ligases
what doe oxidoreductases do
catalyses by redox, transfer of electrons
what do transferases do
transfer functional groups
what do hydrolases do to catalyse
they hydrolyse things with H2O
how do the lyases catalyse
non hydrolytic breaking of bonds;
how do isomerases catalyse
:transfer of atoms/ group within a molecule to yield an isomeric form
how do ligases catalyse
join two molecules together
what are the two classes of cofactor
metal ions and coenzymes
what are metal ion cofactors and how do they work, what do they help with
they are lewis acids (electron acceptors) so they can do acid base reactions, metal ions can form coordination compounds, these coordination bonds can help position reactants where they need to be.
what are coenzymes and what do they do
they are small organic molecules, are co substrates, they are often carriers of electrons, atoms or functional groups.
where are coenzymes derived from
often derived from vitamins
what is PLP a cofactor for
glycogen phosphorylase
how does PLP help glycogen phosphorylase activity.
Pyridoxal phosphate PLP is at the centre of glucose phosphorylase. PLP in this sits right next to the reactant. It sits right next to it as PLP is good for donating a proton to the phosphate group so that it can cleave a glucose from glycogen.
