22.5 Microorganisms, Medicines & Bioremediation

Question 1

How is penicillin produced?

Answer 1

SEMI-CONTINUOUS BATCH process

• process uses small fermenters
  
  • difficult to maintain high O2 concentration in large bioreactors
• mixture continuously stirred >> maintain high [O₂]
• Rich nutrient medium used
• growth medium contains buffer >> maintains pH around 6.5
  
  • penicillum chrysogenum sensitive to changes in conditions
• bioreactors maintained @ 25°C-27°C

Question 2

How is insulin produced commercially?

Answer 2

E.Coli genetically engineered to produce insulin

animal welfare no longer issue

produces pure insulin - less allergic reactions

Question 3

What are the 2 different approaches for bioremediation?

Answer 3

• USING NATURAL ORGANISMS
• USING GM ORGANISMS

Question 4

Describe how natural microorganisms can be used in bioremediation:

Answer 4

• pollutants are often biological/found naturally (e.g sewage, crude oil)
• naturally occuring microorganisms which break down pollutants are given nutrients to encourage proliferation (e.g in oil spills)
• pollutants broken down

Question 5

Describe how GM organisms can be used in bioremediation:

Answer 5

• development of bacteria which break down specific pollutants
• specifically pollutants which are not found naturally
  
  • which current bacteria cannot break down