enzyme quiz Flashcards
Class: oxidoreductase
What type of reaction and how to name
Transfer of electrons from one molecule to another
name: electron donor:electron acceptor + oxidoreductase
Class: transferase
What type of reaction and how to name
Transfer of functional groups from one molecule to another
name: reactant recieving functional group + functional group + transferase
Class: hydrolase
What type of reaction and how to name
Bond cleavage or formation with the addition or removal of water
name: compound to be cleaved + hydrolase
Class: Lyase
What type of reaction and how to name
Group elimination to form a double bind (can result in -C bond cleavage)
name: if no c-c bonds broken, then compounds with a single bond + lyase
if c-c bonds are broken, then compound with c-c bond cleaved + synthase
Class: isomerase
What type of reaction and how to name
intramolecular rearrangements
name: reactant + isomerase
Class: Ligase
What type of reaction and how to name
Bond formation (or breaking) coupled to ATP hydrolysis (or formation)
name: both reactants + ligase
compound formed + synthetase
dehydrogenase
transfer a hydride ion (usually to an acceptor); subclass of oxidoreductase
oxidase
transfer electrons to oxygen; subclass of oxidoreductases
reductase
transfer of a hydride ion (usually from an acceptor); subclass of oxidoreductases
Kinase
transfer of phosphate (phosphoryl group) between any compound and the adenylates (AMP, ADP, ATP); subclass of transferases
Aminotransferase (transaminase)
Transfer of amino group between the compounds; subclass of transferases
phosphatase
hydrolysis of a single bond between a compound and a phosphate group producing inorganic phosphate; subclass of hydrolases
protease
hydrolysis of a peptide bond; subclass of hydrolases
glycosidase
hydrolysis of a glycosidic bond; subclass of hydrolases
synthase
breaking of a double bond of one compound and concomitant formation of a new carbon-carbon bind with a second compound to form a new single compound; subclass of lyase
hydratase
removal of water to form a double bond; subclass of lyase
mutase
the apparent migration of a functional group from one position on a compound to another position on the same compound
Proximity and orientation mechanism definition
substrate is bound in the proper alignment to and next to catalytic amino acids
how to recognize proximity and orientation mechanism
substrate binding to active site
general purpose of proximity and orientation mechanism
increase reaction rate by limiting diffusion and maximizing alignment of reacting functional groups
preferential binding of the TS mechanism definition
enzymes bind transition state with higher affinity than substrates or products
how to recognize preferential binding of TS mechanism
additional contacts made to unstable intermediate (TS) relative to substrate/product
general purpose of preferential binding of TS mechanism
increase reaction rates by lowering transition state energy
acid/base catalysis mechanism definition
enzyme donates or accepts a proton (can be to another amino acid or substrate)
how to recognize acid/base catalysis mechanism
a protonated amino acid becomes deprotonated/a deprotonated amino acid becomes protonated
acid/base catalysis mechanism general purpose
stabilize leaving groups, increase nucleophilicity, stabilize transition state
covalent catalysis mechanism definition
enzyme forms a covalent bond with the substrate
how to recognize covalent catalysis mechanism
deprotonated amino acid nucleophilically attacks substrate (forming a covalent bond)
covalent catalysis mechanism general purpose
facilitate bind cleavage, provides a new reaction pathway
electrostatic catalysis mechanism definition
charge on the enzyme interacts with a neighboring charge
how to recognize electrostatic catalysis mechanism
charge on the enzyme interacts with a neighboring charge
electrostatic catalysis mechanism general purpose
substrate specificity/orientation; stabilize charges forming
metal ion catalysis mechanism definition
metal ion in the active site participates in catalysis
how to recognize metal ion catalysis mechanism
metal ion in the active site
metal ion catalysis mechanism general purpose
charge stabilization, water ionization, electron transfer
