Term
| Class of Enzymes that are unidirectional |
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Definition
| Hydrolases, Lyases, Ligases |
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Term
| Michaelis Menton kinetics |
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Definition
When v = 1/2 Vmax Km = [S]
Lower Km = higher affinity
V = (Vmax *[S]) / (Km+[S]) |
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Term
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Definition
Double reciprocal of Michaelis Menton graph.
Gives linear data
X-intercept = -1/Km
y-intercept = 1/Vmax |
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Term
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Definition
Substrate and inhibitor compete for
active site
Km increases but Vmax stays the same.
Statins: block rate limiting enzyme of
cholesterol synthesis
Allopurinol: Blocks uric acid production |
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Term
| Non-competitive inhibitor |
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Definition
Seperate binding sites for substrate and inhibitor.
Vmax reduced but no change in Km
(Binding of inhibitor decreases turnover of enzyme) |
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Term
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Definition
Permanent covalent adduct formed
Organophosphates(pesticides) bind permanently to AchE
(acetylcholine esterase)
Inhibition of cycloxygenase(Cox1,2) by
aspirin.(binds to serine residue at
active site) |
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Term
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Definition
Respond to ligands other than their substrates.
Can affect Km(k-type) or Vmax(V-type)
Positive(activation) Decreases Km.
(Increases affinity)
Allosteric enzymes show sigmoid curve.
Monomeric(michaelis menton) hyperbolic |
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Term
Catabolic Vs Anabolic
Energy Charge |
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Definition
Catabolic: Energy yielding pathways
(NADH, ATP, etc.)
Anabolic -> Uses ATP, NADH to make
proteins, lipids, nucleic acids etc.
High EC: Synthetic pathways activated
Low EC: Activate ATP generating sequences |
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Term
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Definition
Modifies histidine residue on
eukaryotic TF eEF2.
NAD+ donates ADP-ribose to histidyl
residue on eEF2. (blocks protein
synthesis)
Impedes breathing, swallowing. Sore thorat. |
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Term
| Covalent modification by Phosphorylation |
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Definition
Pi group attached or deattched at
reactive (-oh) groups of serine,
threonine, Tyrosine.
Bulky and heavily charged PO4-3 group
affects internal electrical environment |
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Term
| Cardiac infarction muscle proteins |
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Definition
Creatine Kinase specific for cardiac
infarction. Peak at 24 hours.
Troponins: Peak between 8-28h for cardiac infarction. (more reliable)
LDH peaks at 36-48 hours |
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Term
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Definition
Lacks enzyme to break down phenylalanine
Prevents normal brain development -> mental retardation.
1. Transamination to phenyl-pyruvate
2. Reduction or decarboxylation to Phenyl-acetate, Phenyl-lactate(musty oder) |
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