Because bacteria are so small, we use measurements called MICRONS to measure them. 1 mm = 1000microns Bacteria are much smaller than animal cells. The normal control of bacterial activity depends on its chromosomal material Bacteria

Single Bacterium circular chromosomegene plasmid cytoplasm A bacterium has one chromosome in the form of a complete circle and one or more plasmids. The chromosome and plasmid are made up of genes, each of which contains the instructions to make a certain protein.

Genetic engineering can alter an organisms chromosomes by; 1.Adding new genes (often from a different organism) 2. Removing undesirable genes (eg. Those that may cause disease) 3. Increase the number of copies of a desirable gene already in the organism. Genetic engineering

Genetic Engineering Genetic Engineering is very important to biotechnology. It directs microbes to make products they would not normally make. Pieces of chromosomes (genes) can be transferred from a different organism into bacteria and so allow bacteria to make new substances useful to humans, such as Insulin (control blood sugar), Human Growth Hormone (encourage growth in abnormally small children), and Factor VIII (required for blood clotting).

Genetic Engineering Genetic engineering using living cells involves many specialised techniques. These techniques produce bacteria with altered plasmids. The plasmids can multiply and instruct the cells to make products useful to humans. When many such bacteria are grown together, large amounts of useful products can be obtained rapidly. CREDIT

Insulin Production Insulin is a “chemical messenger” (hormone) produced in the pancreas. It keeps the blood sugar at the correct level. Some people cannot produce insulin and suffer from the disease diabetes. A functioning human insulin gene can be removed from a non-diabetic and incorporated into the plasmid of a bacterium, which is then able to produce human insulin. CREDIT

1.Chromosome extracted and insulin gene identified 2. Gene cut out 3. Plasmid extracted 4.Plasmid cut open5. Gene inserted into plasmid 6. Plasmid inserted into bacterial host cell 7. Bacterium grows and multiplies 8. Insulin mass produced by duplicates of plasmid CREDIT

Insulin The increase in world numbers of people suffering from diabetes, and also the fact that diabetics are living much longer, has increased the demand for insulin. Animal insulin could therefore be in short supply, whereas genetically engineered insulin can be produced in any quantity required to meet the needs of diabetics. CREDIT

Insulin Cattle and pig insulin are different in structure from human insulin and in some diabetics can bring about an allergic response. This may have long-term side effects such as eye and liver damage. Genetically engineered insulin has almost exactly the same structure as human insulin and therefore allergic responses are less likely to occur. Some diabetics do not like injecting themselves with insulin that comes from animals and prefer the ‘human’ insulin produced by bacteria. CREDIT

Other Important Products Other important products of genetic engineering are antibiotics and vaccines. Antibiotics are chemicals that can kill certain microbes. Vaccines are used to prevent disease. Thanks to genetic engineering, both can be produced more easily, quickly and in much larger quantities that before. CREDIT

Cloning Genetic engineering may be used to alter chromosomal material in an animal egg. This involves inserting the required gene into a suitable egg which, when fertilised, develops with altered characteristics. When the whole nucleus of an egg is removed and replaced with the nucleus of a normal body cell from another animal of the same type we call it cloning eg. Dolly the sheep. Unfortunately there can be problems as the genes used are ‘old’ – dolly developed arthritis at an early age. CREDIT

Cloning How to clone a sheep Collect a cell from a sheep (A)Collect an unfertilized egg from a sheep (B) and remove the egg’s DNA Cell with DNA Egg without DNA CREDIT

Genetic Engineering Verses Selective Breeding ComparisonGenetic Engineering Selective Breeding Time taken to improve genotype of animal or plant ImmediateMany years Improved or completely new genotype Possibly completely new genotype Improved genotype Direct or indirect alteration of genotype Direct manipulation of chromosomes Indirect – results are ‘hit or miss’ CREDIT

Genetic Engineering and Potential Hazards There are risks involved in reprogramming microbes. In altering a cell’s instructions a new form of life may be created. New strains of bacteria created by genetic engineering could be harmful to animal and plant life. CREDIT

Detergents

Biological Detergents In the past, one way to remove stains was to boil the fabric in water with a detergent. Many modern man-made fabrics however, are damaged by high temperatures. Also the heat energy used is expensive. Some detergents are called “Biological” and offer a solution to these problems. Biological detergents contain enzymes produced by bacteria

Biological Detergents These detergents contain enzymes such as proteases and lipases. These enzymes help to break down stains caused by proteins like egg, milk and blood. The stains are broken down by the enzymes into soluble substances, which can be washed away. Biotechnology is responsible for the manufacture of these detergents. The enzymes are produced by bacteria and then added to the washing powder. CREDIT

Antibiotics in Action In 1928 a Scotsman called Alexander Fleming discovered the first antibiotic – a chemical which prevents growth of some bacteria. This substance was named penicillin and was the first known antibiotic (something which kills microbes). Since then many other antibiotics have been discovered and used against diseases caused by bacteria. Any one antibiotic is not effective against all bacteria. A bacterium is sensitive to an antibiotic if its growth is prevented by the antibiotic. A bacterium is resistant to an antibiotic if its growth is not affected. CREDIT

P E S C Plate containing bacteria multidisc P = penicillin E = erythromycin S =sulphafurazole C= chloramphenicol In this example, chloramphenicol has the greatest area of clearing and is therefore the best antibiotic to get rid of this infection. Multidisc If someone has an infection and the doctor wants to know which antibiotic would be the most effective, the hospital would culture some bacteria from the infection and use a multidisc to quickly identify the best antibiotic to use. Area of clearing CREDIT

Antibiotics CREDIT