Exam 3 - Reactions Flashcards
What is a nucleophile?
The electron rich species (anions, heteroatoms with lone pair electrons)
What are catalysts?
- They are enzymes and cofactors that increase the rate of of reaction by lowering the energy of activation
- They can make a non-spontaneous reaction spontaneous
- They are not consumed or a part of the product of the reaction
What is an electrophile?
Electron poor species (carbocations, carbonyl groups)
What occurs in an acid base reaction?
What are the types?
Form a reactive species
Bronsted-Lowry: Proton donors (acids) and proton acceptors (bases)
Lewis: electron donors (bases) and electron acceptors (acids)
Does not need a catalyst
What occurs in a nucleophilic substution reaction?
What enzyme catalyzes these reactions?
Addition of an electron rich species (nucleophile) to an electron poor species (electrophile)
Catalyzed by transferases
What occurs in an aromatic substitution?
What enzyme catalyzes these reactions?
substitution of a H on an aromatic ring with another group (not oxygen or nitrogen- that would be REDOX)
Catalyzed by transferases
What occurs in an acyl substitution?
What enzyme catalyzes these reactions?
Addition of a nuclephile to a carbonyl containing group, sulfonate, or phosphate group.
Catalyzed by hydrolases when bonds broke using water, transferases without water
What occurs in an elimination reaction?
What enzyme catalyzes these reactions?
A group is removed from the molecule, typically forming a double bond.
Catalyzed by lyases
What occurs in an addition reaction?
What enzyme catalyzes these reactions?
Adding a group to the molecule, typically forming an OH group.
Catalyzed by ligases
What occurs in a REDOX reaction?
What enzyme catalyzes these reactions?
Increase/decrease in the number of bonds to O,N or H. Oxidation and reduction reactions occur as a pair. If something is oxidized, something else is reduced.
Catalyzed by oxidoreductases
What occurs in an isomerization reaction?
What enzyme catalyzes these reactions?
Rearrangement of groups within the same molecule.
Ex: a group going from a wedge to dash
Catalyzed by isomerases
What are cofactors? What are the types?
- Non-proteins that allow an enzyme to perform it’s role by binding within an enzyme
- Inorganic: Ions = Mg, Zn, Cu, Fe, Ni
- Organic: Coenzymes = typically derived from vitamins
