Microorganisms, medicines & bioremediation

What microorganism is used to produce penicillin (biotech process)

Mold (fungus) (P. Chrysogenum)

What sort of batch process is used to produce penicilin?

Semi-continuous batch process

What are the 3 steps of penicillin production?

1. Fungus grows

2. Fungus produces penicillin

3. Drug is extracted from the medium & purified

What are the conditions used to produce penicillin (5)

1. Uses rel. small fermenters (to maintain high oxygenation levels)

2. Mixture continuously stirred to keep it oxygenated

3. There is a rich nutrient medium

4. Growth medium contains a buffer to maintain pH at around 6.5

5. Bioreactors maintained at about 25-27 degrees Celsius

What type of genetically modified organism can produce insulin? How?

Bacteria

• Grown in fermenter

• Undergo downstream processing

Process of production of human insulin (5)

1. Gene for making human insulin is cut out of human genome using restriction endonucleases, leaving complementary sticky ends.

2. The gene is inserted into a bacterial plasmid using DNA ligase to form recombinant DNA.

3. Recombinant plasmid inserted into bacteria through transformation e.g., electroporation

4. Bacteria grown in continuous fermenter under optimal conditions (pH, temp, oxygen) to maximize growth.

5. Mixture removed and insulin extracted via downstream processing

Bioremediation

Use of biological systems to remove soil & water pollution

• Microorganisms used to break down pollutants & contaminants in soil/water

• Use of microorganisms or plants to break down pollutants and contaminants in soil or water often carried out on site

What are the 2 ways to carry out bioremediation?

1. Using natural organisms

2. Using GM organisms

How does the use of natural organisms work in bioremediation?

Many microorganisms naturally break down organic material to produce CO2 + H2O

• Soil & water pollutants ofen biological (sewage, crude oil)

• If naturally occurring microorganisms supported, they’ll break down & neutralise many contaminants

How does the use of GM organisms work in bioremediation?

Scientists try to develop GM bacteria that can breakdown or accumulate contaminants they wouldn’t naturally occur in

• e.g. bacteria engineered to remove mercury contamination from water

Why is bioremediation often carried out at site of contamination?

1. Area of contamination may be very large so not practical to remove contaminated material/too expensive to remove contaminated material

2. Organisms involved in bioremediation grown & break down contaminants in situ

3. Living organisms so they grow and spread

4. May be harvested and contaminants retrieved

What types of metabolites are penicillin and insulin?

• Insulin → Primary (made continuously by bacteria)

• Penicillin → Secondary (made in batches by fungus / mold)