Transcript f215 biotechnology students version

F215 5.2.2 Biotechnology
By Ms Cullen
What is biotechnology?
• Can also be known as biotech.
• Refers to any technological or industrial use of
organisms (or components of organisms), to
produce products or processes for a specific use.
• Examples:
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medicine
agriculture
food processing
aquaculture
non-food industrial processes
environment
Medicine
Pharmaceutical
production
Diagnostic testing
Antibody testing
Imaging
Gene profiling
Human proteins
Antibiotics
Synthetic drugs
Vaccine
development
Traditional vaccines
Recombinant vaccines
Gene Therapy
Vectors for gene therapy
Gene delivery systems
Organ Transplants
Organ transplant
Xenotransplant
Stem cell technology
Food Production and Processing
Agriculture & Aquaculture
• Inherited disease
resistance
• Herbicide / insecticide
resistance
• Increased nutritional
value
• Improved stress tolerance
• Increased production rate
Food Processing
• Fermentation technology
• Enzymatic modification
• Improved process control
and efficiency
• Enhanced characteristics
(eg flavour, shelf life,
nutritional value)
• Diagnostic food testing
Environment
Bioremediation
Organic spills (petroleum)
Metal contamination
Radioactive material
Biosensors
Chemical monitoring
Pathogen monitoring
Water treatment
Pest control
Waste water
sewage
Weed control
Control of feral animals
Industry
Biofuels
Production of fuels using
alternatives to fossil fuels
(eg sugar cane, maize)
Biocatalysts
Synthesis of chemicals
Brewing industry
Pharmaceutical
production
Green plastics
Mining
Production of plastics
using petroleum
alternatives
(eg sugar cane)
Ore leaching
Metal extraction
Coal cleaning
Why are microorganisms used in
biotechnology?
Why are microorganisms used in
biotechnology?
Activity 20
Investigating population growth
The standard growth curve for a culture of microorganisms
Questions:
1. Explain why there is an initial lag in the
growth of a microorganism placed into a new
culture.
2. Suggest how this lag can be reduced when
starting a new culture.
3. Describe the effect on microbial growth of
adding fresh nutrients and removing toxic byproducts.
Primary metabolites
• During the log phase many intermediate metabolic
products are produced, which are needed by the
microbes for growth or to provide energy.
• These are known as primary metabolites and are
produced in excess and will accumulate in the
culture.
• They can then be extracted and purified.
• Primary metabolites form at same rate as the cells
grow, therefore their growth curves are very similar.
• Example: production of ethanol from yeast
Secondary metabolites
• These are organic compounds, but they are not necessarily
essential for survival of the microorganisms.
• They are often produced as defence mechanisms or to allow
the organism to compete with another.
• Many secondary metabolites have beneficial uses to humans
eg morphine, atropine, penicillin
• Secondary metabolites are produced after the active phase of
growth has ended and the culture is in the stationary phase.
• A limited number of microorganisms produce secondary
metabolites, when 1 or more nutrient is depleted from the
growth medium.
• Many important antibiotics are produced as secondary
metabolites from bacteria and fungi.
Growth and product curves showing the production of (a) a primary metabolite
and (b) a secondary metabolite
Question:
1. Explain why the curve for a primary
metabolite production closely resembles the
microorganisms growth curve.
2. Explain why this is not the case for
production of a secondary metabolite.
3. Explain the differences between a primary
and a secondary metabolite in microbial
culture.
Generalised diagram showing the features of a large-scale industrial fermenter
Fermenter
http://videos.howstuffworks.com/science-channel/29783-100-greatest-discoveries-penicillin-video.htm
Read through biofact sheet 47 on fermentation
Asepsis
• This is the practice of preventing contamination of
cultures by unwanted microorganisms.
Q Why is this important?
Q What aseptic techniques can be
used to prevent contamination?
Industrial Enzymes
Enzymes
• Enzymes are important in commercial and industrial
processes as they accelerate chemical reactions to
produce a useful product or effect.
• Some enzymes used remain in their cells, others are
extracted and purified.
• In each case if the enzymes are trapped within an
insoluble agent their efficiency is increased.
• This is called enzyme immobilisation.
Enzymes and their uses
Enzyme
Substrate
Uses
Proteases
Protein
Washing powder,
leather production,
treatment of blood clots
Amylases
Carbohydrates
Sweetners
Lipases
Lipids
Washing powder
Cellulases
Cellulose
Fabric conditioners, fruit
juice production –
prevents cloudiness
Lactases
Lactose
Producing lactose free
milk
Pectinases
pectin
Fruit juice production
Enzymes
• Enzymes are sourced from a variety of microorganisms,
bacteria, fungi and yeast.
• The bacteria Bacillus and fungi Aspergillus are particularly
useful.
• Microorganisms can be genetically modified to increase the
yield of enzymes they produce.
• The enzymes are purified by grinding cells and/or adding
alkalis. The cell debris is then removed by filtration and
centrifugation.
• The enzymes are then precipitated using ammonium sulphate.
• Further techniques may involve techniques such as filtration,
chromatography and electrophoresis.
Immobilising enzymes
Enzymes are expensive and therefore being able to
recycle them is a cheaper option. The best way to do
this is by immobilising them.
1. An enzyme solution is mixed with a solution of sodium
alginate.
2. Little droplets of this mixture are added to a solution of
calcium chloride.
3. The sodium alginate and calcium chloride react to form a
jelly, which turns the droplets into little beads.
4. The enzyme is held in the bead and is therefore immobilised.
Now have a go yourself! Complete
steps 1-6 of
Activity 22 - Investigating
Immobilised Pectinase
Whilst you are waiting:
Using P.164 -5 in OCR A2 Biology make notes on:
- the advantages and disadvantages of using
immobilised enzymes
- methods for immobilising enzymes
Now complete Activity 22 and
graph your results
Complete Qs for Activity 22
Activity 23 – Investigating
Immobilised Lipase
Draw a graph of your results and
answer Qs