Enzymes Flashcards
Carbonic anhydrase
Zn 2+ , prosthetic
Haemoglobin
Fe , prosthetic
Amylase
Cl– , cofactor
Example of a co- enzyme
NAD+ and FAD+
What do NAD+ FAD+ coenzymes do?
Intracellular, has a role in redox reactions.
Inactive precurser?
An enzyme that must undergo changes to the tertiary structure of the active site.
A protiens catalytically active form is called a
holoenzyme
A holoenzyme consists of…
an apoenzyme and a cofactor/coenzyme
two types of inactive precursors I need to learn?
proenzyme- needs cleaving/ tertiary structure of active site must be broken down.
apoenzyme- needs a cofactor or coenzyme to become a working holoenzyme.
What turns a proenzyme into an active enzyme? (3 things)
- pH change
- temp change
- cleaved by another enzyme
How does aspirin work?
Inhibits enzyme that catalyses reaction that produces cell signalling molecules responsible for pain sensitivity or inflammation.
Temperature coefficient (Q 10) equation…
rate of reaction x +10 °c / rate of reaction x
what does reversible inhibition do?
- removes coenzyme or cofactor
- only create hydrogen bonds with substrate (no ionic or covelant)
- does not denature enzyme
Irreversible inhibition…
- permanently denatures
- creates strong ionic or covelant bonds with enzyme.
Medicines..
inhibit essential enzymes in pathogens
explain the process of end product inhibition…
A sunstance is broken down into products by enzyme 1, and the products of this reaction are broken down by enzyme 2. The products of this reaction are broken down by enzyme 3. the products produced by this enzyme catalysed reaction act as reversible inhibitors to enzyme catalysed reaction 1.
Why does end product inhibition occur?
To regulate how much product is produced.
What is protein specificity?
The specific shape of the teriary structure of an active site. This forms a complex. This also applies to the protien specificity of antibodies and receptor protiens.
Non functional protiens
Mutated or denatured proteins that can not function.
Explain the effects of mutations on protien specificity.
- change in base sequence of DNA or mRNA
- change in primary, secondary, tertiary, and quaternary structure.
- changes shape of binding site
- no longer complimentary.
Explain the effects of denatured protiens on protein specificity?
- increased kinetic energy
- bonds (hydrogen) between R groups of amino acids.
- disulfide bonds not easily broken.
- change to teriary structure of active site.
- no E-S complex can form.
explain an example of end product inhibition…
- the production of ATP
- this involves a series of reactions that transform glucose into ATP.
- ATP molecules inhibit an enzyme in the early stages of the metabolic pathway.
digestion of starch
- first broken down by amylase into maltose
- then broken down into glucose in the small intestine by maltase
V max
point at which all enzymes become saturated.
Anabolic
reactions that build up/ cause growth
catabolic
resction that break down
metabolic pathway
a series of reactions all catalysed by enzymes