Enzymes 2.4 Flashcards
What is the induced fit hypothesis
When the active site (complementary to the shape of the substrate molecule) slightly changes shape to enable the substrate to bind more effectively. This forms an enzyme-substrate complex.
What is a catabolic metabolic pathway
When a larger substrate molecule is broken down into smaller molecules. Releases energy.
What is an anabolic metabolic pathway
When smaller molecules are synthesised to form larger molecules. Energy is used.
What is a cofactor
substance needed by enzymes to ensure reaction takes place at the appropriate rate. Some cofactors (prosthetic groups) found within enzymes structure, others (coenzymes or co-substrates) form temporary associations with the enzyme or substrate.
what is the equation for Q10 (increase in rate of reaction when temperature is increased by 10’C.
rate of reaction at (T+10)’C / Rate of reaction at T’C
How does pH effect enzyme activity
Excess H ions will interfere with H bonds and ionic forces on active site. This causes active site to change shape.
What are the effects of snake venom? (enzyme inhibitor)
-Inhibits AChE (enzyme) which breaks down ACh (neurotransmitter)
-Makes ACh stay attached to muscle receptors and keeps muscle contracted
-This causes paralysis
What does (potassium) cyanide (KCN) do? (enzyme inhibitor)
- gets hydrolysed once ingested to produce hydrogen cyanide
-This can dissociate into H^+ and CN^- ions
-CN^- binds irreversibly to enzyme in mitochondria
-Inhibits aerobic respiration
How does aspirin act by enzyme inhibition
-Prevents formation on prostaglandins (that make nerve cells more sensitive to pain + increases swelling)
-Can reduce blood clots, and risk of strokes
Describe what ATPase inhibitors do…
- treat heart failure and atrial arrhythmia
Inhibit sodium potassium pump
so more calcium ions can enter the cell
Calcium ions increase muscle contractions and strengthens heartbeat.
Describe what ACE inhibitors do
-Inhibits ACE which operates in metabolic pathway that increase your blood pressure
Used: To lower blood pressure in patients with hypertension
To treat heart failure
To minimise risk of second heart attack/stroke in patients who have suffered a myocardial infarction
Protease inhibitors function
Treat some viral infections
Inhibit protease enzymes so that viral coats cannot be made
nucleoside reverse transcriptase inhibitors
inhibit enzymes that make dna using a viral rna template instead
