Microbial Metabolism- pt. 1

Question 1

What is Metabolism?

Answer 1

All chemical and physical reaction in cells

Question 2

What are the two forms of metabolism?

Answer 2

1) Anabolism
2) Catabolism

Question 3

What three things does metabolism accomplish?

Answer 3

1. assembles small molecules into macromolucules (anabolism)
2. degrades macromolecules into smaller molecules (catabolism)
3. Creates and uses energy in the form of ATP or Heat​

Question 4

What are the 3 forms of work?

Answer 4

1. chemical
   
   1. ​energy required for synthesis of molecules
2. Trasnport
   
   1. ​Energy required to move molecules in/out of cells
3. Mechanical
   
   1. ​energy required for cell motility

Question 5

Why are enzymes considered a catalyst?

What type of molecule are enzymes?

Answer 5

They speed up reactions

• Macromolecules

Question 6

How do enzymes work?

Answer 6

• Contain an active site/sites
• Promote a reaction by binding a specific substrate

Question 7

What type of macromolecule are enzymes typically?

Answer 7

Protein

Question 8

What are the types of enzymes?

Answer 8

1. Simple enxymes
   
   1. a protein by itself
2. Conjugated enzymes
   
   1. apoenzyme+cofactors
3. ribozyme
   
   1. Enzyme made of RNA

Question 9

What are the cofactors of enzymes?

Answer 9

1. Trace Metals
2. Coenzymes (vitamins)

Question 10

What do trace metals do in enzymes?

Answer 10

Activate enzymes (bring active site and substrate together)

Participate in chemical reaction

Question 11

What do coenzymes do in enzymes?

Answer 11

Remove chemical groups from on substrate to another

Question 12

What are the differences between exoenzymes and endoenzymes?

Answer 12

Both are produced inside the cell.

• Exoenzymes are transported outside cell to break down food molecules and harmful substances
• Endoenzymes stay inside cell and are used for cell’s metabolic processes

Question 13

What are:

• constitutive enzymes?
• regulated enzymes?

Answer 13

• constitutive= Always present in constant amounts (adding more substrate does no change concentration)
• Regulated= Production has to be turned on/off based on substrate concentration

Question 14

How do enzymes affect reaction rates?

Answer 14

Increase reaction rates by lowering the activation energy

Question 15

How do substrate concentration affect enzyme activity.

What is the limiting factor in this?

Answer 15

Substrate concentration

high substrate=high activity

low substrate = low activity

• Activity will not increase above saturation

Question 16

What is competitive inhibition of an enzyme?

Answer 16

Inhibitor binds to catalytic site and prevents enzyme from forming product.

Question 17

What is non-competitive inhibition?

How does it affect the enzyme?

Answer 17

Inhibitor inhibits activity at different site (not catalytic site)

Usually alters enzyme shape (enzyme becomes inactive)

Question 18

Give a competitive inhibition example:

Answer 18

Sulfa: resembles PABA

Competes for catalytic site on enzymes for folic acid synthesis

Question 19

What is enzyme repression?

Answer 19

Stopping enzyme synthesis when end product has been made to excess.

Question 20

What is enzyme induction

Answer 20

Synthesis of enzyme is turned on when substrate is present

Question 21

What are:

• exergonic reactions
• endergonic reactions

Answer 21

• Exergonic=

Reaction that results in release of energy

• endergonic

Reaction that results in the use of energy