biotechnology Flashcards
What is biotechnology?
The use of living organisms/ biological molecules in the production of useful products e.g. food, drugs.
Primary metabolite.
Any substance produced by a microorganism (bacteria/fungi) during its normal metabolism and growth.
Secondary metabolite.
Any substance produced by a microorganism once it has stopped growing.
Reasons why microorganisms are ideal for use in biotechnology, rather than other organisms.
- No welfare issues.
- Easy to create optimum growth conditions.
- Huge range of different species of microbes - potential to carry out lots of different reactions.
- Microbes are easy to modify, so they can be engineered to produce human products that they wouldn’t normally make.
- Short life cycle and rapid growth rate - huge amount of product can be made in short amount of time.
- Very simple and cheap nutrient requirements.
- Their cells/enzymes work at relatively low temperatures and pressures - again cheaper.
Yeast cannot respire starch, so the grains are soaked to trigger them to germinate.
As the barley grains start to germinate, the enzyme AMYLASE is activated inside them.
What does this enzyme do, and how will it benefit the yeast?
Amylase converts the starch in the grains into maltose (disaccharide). The yeast can then use this for respiration producing ethanol.
For yoghurt production of by will the reaction stop when the pH reaches 4.3?
This is a low acidic pH and it will inhibit the enzyme activity in the bacteria.
The bacteria will then die - reaction stops.
How can some cheese be labelled as “V” when many aren’t?
For a cheese to be vegetarian, the rennet used in production comes from genetically engineered bacteria, rather than from calf stomachs.
Quorn is an example of SCP. What does this mean?
Single Cell Protein.
What are the advantages of eating quorn?
Vegan/vegetarian.
Low fat/low cholesterol.
High protein content.
Advantages of using microorganisms to produce human food.
- Microorganisms reproduce fast and produce protein faster than animals and plants.
- Microorganisms have a high protein content with little fat.
- Microorganisms can use a wide variety of waste materials including human and animal waste, reducing costs.
- Microorganisms can be genetically modified to produce the protein required.
- Production of microorganisms is not dependent on weather, breeding cycles etc - it takes place constantly and can be increased or decreased to match demand.
- No welfare issues when growing microorganisms.
- Can be made to taste like anything.
Disadvantages of using microorganisms to produce human food.
- Some microorganisms can also produce toxins if the conditions are not maintained at the optimum.
- The microorganisms have to be separated from the nutrient broth and processed to make the food.-costly and time consuming.
- Need sterile conditions that are carefully controlled adding to costs.
- Often involve GM organisms and many people have concerns about eating GM food.
- The protein has to be purified to ensure it contains no toxins or contaminants.
- Many people dislike the thought of eating microorganisms grown on waste.
- Has little natural flavour.
What are the other uses for microorganisms in biotechnology, besides food production?
- Medical products for humans
- Bioremediation.
What is penicillin and how is it grown?
- This is an antibiotic made by the fungal mould penicillium chorosogenum.
- It requires a high concentration of oxygen and nutrients in order to grow well.
- It is grown in small batches in fairly small fermenters, large fermenters would be too difficult to keep oxygenated.
What is the “batch-fed” method?
Nutrients are added at regular intervals, rather than just at the start.
What type of metabolite is penicillin and why?
It is a secondary metabolite as it is produced after the fungus has stopped growing.
What is “downstream processing”?
Refers to the steps needed to purify the product that is harvested from the fermenter before it is fit for human use. This may involve separating useful products from any contaminating products and concentrating the product.
A lot of fungi make antibiotics, why do you think that they are always secondary metabolites?
Once a fungus has put energy into growing and established itself, it is useful to produce antibiotics to inhibit the growth of any nearby competing bacteria (which may compete for limited resources).
How is insulin now produced?
Bacteria are grown in huge fermenters, they produce the insulin, which is then extracted/concentrated/purified for sale.
What are the main advantages of producing insulin this way?
- Supply can now meet demand.
- Continuous production possible.
- No allergic reactions.
- No ethical/religious objections.
What is bioremediation?
The use of microorganisms to remove toxic substances/pollutants from the environment.
These could otherwise accumulate in food chains, causing harm to many other living organisms.
What are the two main ways that bioremediation is used?
Using natural organisms - break down organic matter to CO2 and H2O.
GM organisms - GM bacteria to break down / accumulate contaminants that they would not naturally encounter.
