0214 Generic strategies in metabolic organisation and regulation Flashcards
Metabolism comprises anabolism & catabolism Anabolic and catabolic pathways are coupled Futile cycles NOT desirable Pathways and cycles are found in metabolism Controlling enzymes controls pathways Only key enzymes are regulated Nutrients have multiple fates Starting materials must face a committed step Compartments facilitate metabolism & control fluxes
What are roles of metabolic pathways (hint: 7 main roles)
- Death
- Repair
- Storage
- Growth
- Provision
- Motion
- Communication
(Doctors say good patients must communicate)
What is the role of complexity of metabolic pathways
- Directing flux
- Regulation of processes
- Integration of multiple pathways
- Commitment of resources
- Energy Efficiency
D.R. I.C.E.
Describe some ways that futile cycles are minimized in our bodily processes
Reciprocal regulation (one signal = distinct responses) Substrate availability (compartmentalisation, directing flux) Co-factor availability
What is the consequence of enzyme clustering and where are enzymes commonly clustered
Enzyme clustering allows for rapid passage of subtrates, easy regulation and prevents loss of unstable intermediates. Enzymes are commonly clustered on membranes (e.g. the endoplasmic reticulum)
What are the 2 types of reactions in regards to ATP. What ones are more favourable
Reactions can be linked to either ATP production (G-ive) or ATP hydrolysis (G+ive). ATP is favourable while ATP hydrolysis is usually unfavourable
What is the role of branches in metabolic pathways
Branch points in pathways let us regulate the flux of a certain reaction by ‘’siphoning’’ intermediates when we have excess product. This is especially important in pathways with committed steps where branching points before the committed step will reduce flux
What is a futile cycle and why is it unwanted
Futile cycles occur when two metabolic pathways run simultaneously in opposite directions and have no overall effect. They are prevented because they are extremely inefficient and costly
What are the 2 enzyme changes that can regulate metabolic activity. Which one is long term and which one is short term
Enzymes can regulate processes by a change in the concentration of enzymes or a change in the effectiveness/activity of enzymes. Amount = long term. Activity = short term
