Microbial Biotechnology BIOL410
Microbial Biotechnology
BIOL410
Course outline• Introduction: microbial biotechnology scope and history• Microbial Diversity• Microbial metabolism• Fermentation • Microbial Biotechnology in Agriculture and Aquaculture• Overview session• Mid Term Exam• Production of Proteins in Bacteria and Yeast• Recombinant DNA technology• Medical applications• Food technology• Bioremediation• Environmental Applications of Microorganisms• Overview session• Final exam
Industrial Microbiology
• Humans were using microbes even before they knew about their existence
• As the knowledge of microbes grew , humans improved & expanded their uses
• Now managing these microbe has become a science
Uses of Microbes
• Antibiotics• Vitamins• Food supplements• Industrial chemicals• Recombinant DNA technology
Microbes Are Everywhere!
• In the soil
Microbes Are Everywhere!
• In thermal areas
Microbes Are Everywhere!
• In ice
Microbes Are Everywhere!
• In salt
Microbes Are Everywhere!
• In water, viruses outnumber bacteria by 2-10:1
Microbes Are Everywhere!
• In the deeps
Microbes Live Together
• In biofilms in pipes
Microbes Live Together
• On your teeth
And with other organisms
• With plant roots
And with other organisms
• In coral
And with other organisms
• In clams
And with other organisms
• In lichens
And with other organisms
• With cows and termites
And with other organisms
• With fish
We Use Existing Microbes
• To make foods
We Use Existing Microbes
• To make alcohol
We Use Existing Microbes
• To clean up oil spills
We Use Existing Microbes
• To turn trash into soil
We Use Existing Microbes• To leach ores
We Use Existing Microbes
• To make medical products
Microbiotechnology
1. Traditional uses make & preserve human & animal food
2. As chemical factoriesmake chemicals & drugs
3. Genetically engineered microbes
Traditional usesa. Lactic acid bacteria
– Ferment sugars, – their metabolic products have a
pleasant taste– Used to make dairy products, cheese,
sauerkraut, green olives– With exception of some streptococci
these organisms are harmless to humans
Traditional usesb. Yeasts (Saccharomyces
cerevisiae)– Are as important as lactic acid
bacteria– Ferment sugars & produce ethanol &
CO2– Used in the wine industry– Bread making– To make vinegar 2 step process-
Yeasts ferment sugar to ethanol, then Acetobacter converts that to acetic acid
Mixed cultures
• Cultures of bacteria & fungi• Used to make fermented
foods kefir (laban), soy sauce, miso
Microbial Insecticides• Unlike chemical insecticides these are
ecologically safe• Species of Bacillus are insect pathogens
– B. thuringiensis endospores lethal to insects ( marketed as Bt)
– B. popilliae controls japanese beetles (marketed as Bp)
– Protozoa Nosema locustae bait for grasshoppers & locusts
2 Chemical FactoriesDue to their rapid rate of growth and
metabolism microbes are use to manufacture many commercial products
Can be done:AnaerobicallyAerobically
Anaerobic Fermentations
Most common substrate used is blackstrap molasses
• Ethanol• Acetone• Butanol
Aerobic ProcessesSterilized air must be supplied to prevent
contamination of cultures• Antibiotics• Amino acids used to enhance flavor of
foods• Enzymes wide variety of uses
Genetically Engineered Microbes
• Medical Uses• Agricultural Uses
Medical UsesGenetically engineered microbes use for:Hormones
Human growth hormoneInsulinTissue plasminogen activator binds to & dissolves clots
Vitamins
Agricultural Uses• Bt toxin• Ice minus gene• Better silage makers
Microorganisms and Agriculture
• Ice-nucleating bacteria story• Plant frost damage is caused by the presence
of ice-nucleating bacteria (Pseudomonas, Erwinia, Xanthomonas) on plants
• The ice+ gene on the bacterial chromosome encodes an ice-nucleating protein which allows for ice crystal formation at 0 to 2°C
• When the ice gene is deleted from the bacteria, ice crystal formation (frost damage) does not occur until -6 to -8°C
We Modify Microbes• To protect plants from pests
We Modify Microbes• To clean up toxic waste = bioremediation
We Modify Microbes• Recombinant DNA Technology:
– Insertion or modification of genes to produce desired proteins
We Modify Microbes• To make medicines
Herceptin• Trastuzumab (Herceptin) is a monoclonal antibody that interferes with
the HER2/neu receptor.
• The HER receptors are proteins that are embedded in the cell membrane and communicate molecular signals from outside the cell to inside the cell, and turn genes on and off. The HER proteins regulate cell growth, survival, adhesion, migration, and differentiation—functions that are amplified or weakened in cancer cells. In some cancers, notably some breast cancers, the HER2 receptor is defective and stuck in the "on" position, and causes breast cells to reproduce uncontrollably, causing breast cancer.
• Antibodies are molecules from the immune system that bind selectively to different proteins. Herceptin is an antibody that binds selectively to the HER2 protein. When it binds to defective HER2 proteins, the HER2 protein no longer causes cells in the breast to reproduce uncontrollably. This increases the survival of people with cancer. However, cancers usually develop resistance to herceptin.
Herceptin• Trastuzumab (perceptin) was originally
developed in mice, as a mouse antibody. Because humans have immune reactions to mouse proteins, it was later developed into a human (humanized) antibody. Because the antibodies were produced from one cell that was grown into a clone of identical cells, it is called a monoclonal antibody.
• Cost of treatment: 100 000 $ per year.
Structure of Herceptin
Acrylamide production Biotransformation
• Biotransformation:• Moderate conditions• Yield: almost 100%• No need to remove copper • Enzymatic process being
carried out below 10 C under• mild reaction conditions and
requiring no special energy source
• The immobilized cells are used repeatedly and a very
• pure product is obtained.• The first successful example of
using biotransformation in production of commodity chemicals
Acrylamide is one of the most important commodity chemicals. Its global consumptionis about 200,000 tonnes per year.
It is used in the production of variouspolymers for use as flocculants, additives or for petroleum recovery.
Immobilization (cell, enzyme)
• “Immobilized” means unable to move or stationary – an microorganism (or enzyme) that is physically attached to a solid support over which a substrate is passed and convert to product.
SummaryMicrobial Application
Problems with Biotechnology
• Transfer of genes found in transgenic organisms to natural populations.– Terminator genes have been used to
minimize this risk
Problems with Biotechnology
• Unexpected impacts of genetically modified organisms and biotechnology processes on other organisms and the environment
Problems with Biotechnology
• Expense of the utilization (research) of many biotechnology techniques
What Are Bioethics?• Ethics- knowing right from wrong,
and then doing the right idea• Bio- living organisms• Bioethics- knowing right from
wrong with living organisms, and then doing the right idea
• http://www.oelwein.k12.ia.us/hs/Ag.Home/biotechethics.htm