Chapter 2.1 Flashcards
Do catalysts affect the enthalpy of a reaction, equilibrium constant of a reaction or the gibbs free energy change
-no
What are oxidoreductases responsible for? Name examples
- they are involved in oxidation/reduction reactions
- > transfer of electrons between biological molecules
- > often have a cofactor that acts as an electron carrier
- electron donor is the reductant
- electron acceptor is known as the oxidant
-dehydrogenase, reductase and oxidase are examples
What are transferases responsible for? Give examples
- transfer the movement of a functional group
- > from one group to another
eg; kinases
->they transfer a phosphate group from one molecule to another
What are hydrolases? Give examples
- catalyze the breaking of a compound
- > into two molecules
- > using the addition of water
- > eg; phosphatase, peptidases, nucleases and lipases
What are lyases? Can they reverse the breakdown of their reactions?
- catalyze the cleavage of a single molecule into two products
- > do not require water as a substrate
- > do not act as oxidoreductases
- they can also catalyze the reverse of reaction
- > so make a single molecule from two reactants
- > in this case, the lyase becomes a SYNTHASE
-generally for synthesis, they create smaller molecules than ligases
What are isomerases?
- they just rearrange bonds within a molecule
- > can be classified as oxidoreductases, transferases, lyases
- > depends on the mechanism of the reaction
What are ligases? What important molecule do they require for these reactions?
- they catalyze addition or synthesis reactions
- > generally between large molecules
- > often require ATP
-most likely to be encountered in nucleic acid synthesis
Can enzymes affect how fast a reaction reaches equilibrium
- yes
- >but they do not equilibrium itself
