Flashcards in Lecture 11 - Enzymes I Deck (31)
The most common of all enzymatic reactions.
Redox (oxidation-reduction) reactions.
Primary f(x)s of enzymes
Lower activation energy (Ea) and stabilize the transition state)
How does one increase the production of products (according to Le Chatlier's Principle)?
Decrease [product] or increase [reactants]
What is meant by "coupled reactions" in terms of biochemical reactions?
The energies of a set of reactions are additive. In other words, if A-> B has a (+) G, and B->D has a (-) G, they can be added together. If the sum of both G's is (-), the reaction is OVERALL spontaneous.
These reactions revolve around the transfer of electrons.
Gain of an e-
loss of e-
Gain of H+
Loss of H+
What portion of an enzyme determines specificity for a substrate?
Cleavage of peptide bonds
What is the Vmax?
The maximum rate (reaction velocity) at which a reaction can occur.
What produces a maximum velocity (Vmax) in reactions?
The complete saturation of the active site on an enzyme.
3-D region or crevice that is produced after the residues from various parts of a protein come together in the 3* structure
Highly unstable intermediate in enzymatic reactions
What is the "purpose" of an enzyme (specifically, HOW does an enzyme catalyze reactions)?
by lowering the activation energy of a given reaction
Why are many vitamin deficiencies the cause of enzymatically driven health problems?
Often, vitamins serve as co-factors for enzymes. W/o the co-factor, the enzyme is an "apoenzyme," devoid of function.
An enzyme that contains its co-factor and is biologically active
holoenzyme ("holo-" = "complete")
Two f(x)s of metals as co-factors
Stabilize A.S. and donate e- to the chemical reaction
small organic molecules used as a co-factor
An enzyme w/o its necessary co-factor
Tightly bound co-enzymes are known also as _____.
Pathophysiology of scurvy
A lack of co-factor (Vit. C) for prolyl hydroxylase, prevents addition of -OH in collage
Pathophysiology of ariboflavinosis
A lack of riboflavin (Vit. B2) prevents activation of FAD; this causes decreased glutathione reductase function, and results in UV light damage to areas exposed to the sun through production of free radicals (no FAD to "snag" high energy free radicals)
enzyme that transfers e- between compounds
enzyme that moves f(x) group between compounds
catalyze hydrolysis of covalent bonds
Form double bonds by the addition of removal of groups
transfers a group intra-molecularly
isomerase (forms isomer)