Biotechnology

• Everyday Products Made with Biotechnology

  • Biofuels
  • Bread
  • Fruit Juice Production
  • Biological Washing Powders
  • Lactose-free milk
• Yeast


  A single-celled fungus that uses sugar as its food source
• Fermentation of Glucose


  1. Yeast respires anaerobically

  2. Produces ethanol and carbon dioxide

  3. Energy is released
• Biofuel


  A fuel made from living organisms rather than a fossil fuel like oil, coal or gas
• The alcohol produced by fermentation of glucose can be used as biofuel
• In countries such as Brazil, biofuel is partly replacing petrol as the fuel for cars and other vehicles
• Producing ethanol from plant material

  1. Chop up plant material into small pieces

  2. Mix with yeast

  3. Yeast respires anaerobically

  4. Ethanol is produced

  5. Liquid is separated from solids

  6. Water is removed
• Sometimes the waste parts of crop plants, such as the stalks or outer leaves, are used, but in other places, crops are grown specifically to be harvested for making ethanol
• In some places, this is causing concern that there is less land available for local people to grow food crops needed for survival
• Yeast and Making Bread

  1. Yeast is mixed with flour and water

  2. Yeast respires anaerobically, producing carbon dioxide

  3. Carbon dioxide is caught in the dough, causing the bread to rise
• Fruit Juice Production


  1. Fruit is chopped up

  2. Enzyme pectinase is added

  3. Pectinase breaks down pectin

  4. Cell walls break more easily

  5. More juice can be squeezed out

  6. Juice becomes clearer
• Pectinase


  An enzyme that breaks down pectin, a chemical found inside plant cell walls
• Biological washing powders


  Contain enzymes similar to digestive enzymes that help break down large organic molecules like fats and proteins
• Advantages of biological washing powders

  • Quickly break down large, insoluble molecules
  • Effective at lower temperatures
  • Can be used to clean delicate fabrics
• Lactose


  The sugar found in milk
• Lactase


  The enzyme that breaks down lactose
• Human babies are born with the ability to produce lactase, but many people lose this ability as they get older
• Symptoms of lactose intolerance include nausea, flatulence and diarrhoea
• Using Lactase to Produce Lactose-free Milk

  1. Lactase enzyme is added to dairy milk

  2. Enzyme breaks down the lactose
• Lactose-free milk is a product made by adding the enzyme lactase to dairy milk to break down the sugars in it
• Microorganisms


  Capable of producing complex molecules and reproducing rapidly
• The most common type of microorganisms used in biotechnology are bacteria
• Benefits of bacteria in biotechnology

  • Few ethical considerations to growing them in large numbers
  • Possess plasmids which can transfer DNA
• Plasmids


  Small, circular loops of DNA that can transfer DNA from one cell to another
• Fermenter


  A container used to grow ('culture') microorganisms like bacteria and fungi in large amounts
• Penicillin was the first antibiotic, discovered in 1928 by Alexander Fleming
• Penicillin Production


  1. Penicillium mould produces a chemical to prevent bacterial infection

  2. Chemical was isolated and named penicillin

  3. Methods developed to produce it on a large scale using an industrial fermenter
• Conditions in a Fermenter

  • Aseptic precautions
  • Nutrients
  • Optimum temperature
  • Optimum pH
  • Oxygenation
  • Agitation
  • Waste removal
• Mycoprotein


  A protein-rich food suitable for vegetarians, produced by culturing the fungus Fusarium in fermenters
• Genetic modification


  Changing the genetic material of an organism by removing, changing or inserting individual genes from another organism
• Transgenic organism


  An organism that has received genetic material from another organism
• Recombinant DNA


  The DNA of an organism that now contains DNA from another organism as well
• The gene for human insulin has been inserted into bacteria which then produce human insulin which can be collected and purified for medical use to treat people with diabetes
• Genetic Modification using Bacterial Production of a Human Protein

  1. Locate gene to be inserted

  2. Use restriction enzymes to isolate gene with 'sticky ends'

  3. Cut bacterial plasmid with same restriction enzyme

  4. Use DNA ligase to join gene and plasmid

  5. Insert engineered plasmid into bacterial cell

  6. Bacteria reproduce, copying plasmid and expressing gene

  7. Genetically engineered bacteria placed in fermenter to rapidly reproduce and produce human protein
• Reasons bacteria are useful for genetic engineering

  • Share the same genetic code as other organisms
  • No ethical concerns over their manipulation and growth
  • Presence of plasmids makes them easy to manipulate
• Advantages of Genetic Modification

  • Reduced use of chemicals like herbicides and pesticides
  • Increased crop yields
  • Rapid reproduction rate of bacteria
• Risks of Genetic Modification

  • Increased costs of GM seeds
  • Increased dependency on certain chemicals
  • Risk of gene transfer to wild plants
  • Reduced biodiversity
  • Potential for plants to not grow as well as non-GM
  • Potential for bacteria to pass human genes to other bacteria