1. F215 control, genomes and environment
Biotechnology
F215 control, genomes and environment
Module 2 – Biotechnology and gene technologies

2. Learning Outcomes
State that biotechnology is the industrial use of living organisms (or parts of living organisms) to produce food, drugs or other products.
Explain why micro organisms are often used in biotechnological processes.

3. Biotechnology
Biotechnology is the industrial use of living organisms to produce food, drugs and other products.
Biotechnology has four major applications that affect our lives
Healthcare and medical processes
Agriculture
Industry
Food science

4. Using Micro organisms
Features of micro organisms that make them suitable for large-scale industrial processes
Rapid life cycles
Reproduce asexually
Very specific and simple requirements for growth
Can be grown on waste materials from industry
Does not raise ethical questions
Bacteria have a single copy of each gene
Simple control of gene expressions
Wide range of metabolic pathways
Some evolved to survive at high temperatures

5. Learning Outcomes
Describe, with the aid of diagrams, and explain the standard growth curve of a microorganism in a closed culture.

6. Standard Growth curve

7. Growth curve in a closed culture
Lag phase
Bacteria adjusting to new conditions
Takes a while for enzyme production
Log phase
Number of bacteria increase rapidly
Stationary Phase
Rate of growth is equal to rate of death
Decline Phase
Death rate is greater than “birth rate”
The first three stages represent a sigmoid growth curve

8. Learning Outcomes
Explain the importance of manipulating the growing conditions in a fermentation vessel in order to maximise the yield of product required.

9. Large-Scale production
Microorganisms are cultured in large containers called fermenters
The growing conditions within the fermenter are manipulated and controlled
Precise growing conditions
Temperature
Type and time of the addition of the nutrient
Oxygen concentration pH

10. A batch fermenter

11. Large scale production
Three examples are
The production of penicillin
The production of protease enzymes
The production of mycoprotein

12. Learning Outcomes
Compare and contrast the processes of continuous culture and batch culture.
Describe the differences between primary and secondary metabolites.

13. Metabolism and metabolites
Metabolism (process)
Sum total of all the chemical reactions
Processes produce
New cell and cell components
Chemicals
Waste products
Metabolites (products)
A substance produced during cell processes

14. Primary and secondary metabolites
Primary metabolite
Substance produced by organism as part of it’s normal growth
E.g. amino acids, proteins, enzymes
Production of primary metabolites matches the growth in population
Secondary metabolite
A substance only produced at a particular growth phase
No direct involvement in fundamental metabolite processes
Production usually begins after the main growth phase of the micro organisms

15. Batch culture
Starter population is mixed with a specific quantity of nutrient solution
Allowed to grow for a fixed period
Products removed
Fermentation tank emptied
Examples
Penicillin production
Enzyme production

16. Continuous Culture
Nutrients are added and products are removed from the fermentation tank at regular intervals
Examples
Insulin production from genetically modified E.Coli
Production of mycoprotein

17. Learning outcomes
Explain the importance of asepsis in the manipulation of microorganisms

18. Asepsis Asepsis Aseptic techniques absence of unwanted microorganisms
Any measure taken during a biotechnological process to prevent contamination by unwanted microorganisms

19. The importance of asepsis
Unwanted microorganisms
Compete with the culture microorganisms
Reduce the yield of useful products
Cause spoilage of the product
Produce toxic chemicals
Destroy the culture microorganism or its products.

20. Methods to maintain asepsis
Ensure all fermenters and attachments are sterile
Cleaning with pasteurised steam
Chemical sterilisation
Sterilise all liquids, solids and gases that enter the reaction vessel
Maintain a pressure difference between the air in the room where fermentation is taking place and outside
Maintains a steady airflow out of the room
Ensure culture of microorganisms is pure
Ensure the workers do not introduce unwanted microorganisms from their skin.

21. Learning Outcomes Describe how enzymes can be immobilised.
Explain why immobilised enzymes are used in large-scale production.

22. Immobilising enzymes Enzymes act as catalysts in metabolic reactions
Enzymes are useful in industrial processes
Specificity
Temperature of enzyme action
Enzymes in solution need to be separated from the products.
Immobilised enzymes can be re-used many times and leaves the product enzyme free.

23. Methods for immobilising enzymes
Gel entrapment
Example – immobilising lactase in alginate
Stages
Enzyme solution is mixed with sodium alginate solution
Droplets of this solution are added to a solution of calcium chloride
The droplet turns into a bead which contains the enzyme

24. Immobilising lactase in alginate

25. Immobilising lactase in alginate
The beads can be tightly packed into a column
The liquid substrate can be trickled over the beads
The product trickles out of the bottom of the column
The product is collected and purified.

26. Methods of immobilising enzymes
Adsorption / carrier bound
Enzyme molecules are mixed with immobilising support e.g. glass beads or clay
Covalent Bonding / cross-linked
Enzyme molecules covalently bonded to a support

27. Methods of immobilising enzymes
Entrapment / inclusion
Enzymes trapped in their natural state in a gel bead
Reaction rate can be reduced as substrate needs to get through the trapping barrier
Membrane separation
Substrate separated from the mixture by a partially permeable membrane.

28. Advantages of immobilised enzymes
The advantages of using immobilised enzymes over enzymes in solution are
Immobilised enzymes can be reused
Product is enzyme free
Immobilised enzymes are more tolerant to pH and temperature changes