Microbial World and You

What is Microbiology? Micro - too small to be seen with the naked eye Bio - life ology - study of

Organisms included in the study of Microbiology 1. Bacteria 2. Protozoans 3. Algae 4. Parasites 5. Yeasts and Molds Fungi 6. Viruses Bacteriology Protozoology Phycology Parasitology Mycology Virology Microorganisms - Microbes - Germs

Bacteriology: It is science to deal with the study of the bacteria Bacteriology: It is science to deal with the study of the bacteria. Virology: It is science to deal with the study of the virus. Mycology: It is science to deal with the study of fungi. Immunology: It is the science to deal with the resistance of the body to any foreign substance. Parasitology: It is the science to deal with Parasites.

The importance of microorganisms: Microorganisms are the oldest forms of life. Microorganisms have the greatest biomass. Microorganisms have killed more people than have ever been killed in wars. Without certain microorganism life could not exist; produce O2 and N2 . Microorganisms are decomposers.

BRANCHES OF STUDY WITHIN MICROBIOLOGY Immunology Public health microbiology & epidemiology Food, dairy and aquatic microbiology Biotechnology Genetic engineering & recombinant DNA technology

MICROBES ARE INVOLVED IN Nutrient production & energy flow Decomposition (bioremediation) Production of foods Production of drugs & vaccines Genetic engineering Causing disease

History of the Study of Microorganisms:

1665 Robert Hooke “little boxes” - “cells” Cell Theory - all living things are made up of cells 1590 – First compound light microscope Zacharias Janssen Anton van Leeuwenhoek 1674 who was the first person to actually see living microorganisms

Anton Von Leeuwenhoek 1676 –first observation of bacteria “animalcules *As a tailor, used lenses to examine cloth. It was probably this that led to his interest in lens making. *He assembled nearly 250 microscopes, some of which magnified objects 270 times.

*As he looked at things with his microscopes, he discovered presence of “micro” organisms - organisms so tiny that they were invisible to the naked eye. *He called these tiny living organisms “animalcules”. He first described bacteria and the protozoans.

Edward Jenne 1796 – First vaccine (smallpox) 1857 – Germ Theory of Disease Louis Pasteur Rudolph Virchow 1858 the owner of the Theory of Biogenesis, that said ; Cells can only arise from preexisting cells

1884 Disease transmission Robart koch Koch’s Postulates who established the relationship between Bacillus anthracis and anthrax; also isolated the bacillus that causes tuberculosis 1885 - Vaccine against Rabies Louis pasteur - Developed vaccines for Chickenpox, anthrax, rabies

Demonstrated that all fermentations were due to the activities of specific yeasts and bacteria. Alexander Fleming 1929 Discovery of Penicillin (first antibiotic) British bacteriologist observed bacterial staphylococci colonies disappearing on plates contaminated with mold. Fleming extracted the compound from the mold responsible for destruction of the bacterial colonies.

The product of the mold was named penicillin, after the Penicillium mold from which it was derived 1938 – First Electron Microscope The electron microscope is capable of magnifying biological specimens up to one million times. These computer enhanced images of 1. smallpox, 2. herpes simplex, and 3. mumps are magnified, respectively, 150,000 and 90,000 times. Watson & Crick 1953 Structure of DNA Revealed Jonas Salk 1954 Polio Vaccine

Golden Age of Microbiology 1857 - 1914 Pasteur Pasteurization Fermentation Joseph Lister Phenol to treat surgical wounds – 1st attempt to control infections caused by microoganisms

Robert Koch Koch’s Postulates Edward Jenner Vaccination Paul Erlich 1st synthetic drug used to treat infections Salvarsan - arsenic based chemical to treat Syphilis

Recent history: Genetic engineering Cloning Human Genome Project Biotechnology Who knows what is next?

Sizes of Microbes Virus - 10 →1000 nanometers * Bacteria - 0.1 → 5 micrometers ** (Human eye ) can see .1 mm (1 x 10 -3 m) * One billionth or 1 x 10 -9 m ** One millionth or 1 x 10 -6 m

Microbes - what comes to mind? Diseases Infections Epidemics Food Spoilage Only 1% of all known bacteria cause human diseases About 4% of all known bacteria cause plant diseases 95% of known bacteria are non-pathogens

Microbes Benefit Humans  1. Bacteria are primary decomposers - recycle nutrients back into the environment 2. Microbes produce various food products: cheese, pickles, green olives yogurt, soy sauce, vinegar, bread Beer, Wine, Alcohol 3. Microbes are used to produce Antibiotics: Mold: Penicillin in 1928 by Alexander Fleming

4. Microbial Antagonism: Our normal microbial flora prevents potential pathogens from gaining access to our body

Microbes do benefit us, but they are also capable of causing many diseases: Pneumonia, Whooping Cough, Botulism, Typhoid Fever, Measles Cholera……………

Tools of Microbiology Compound light Microscope - live specimens - 1,000 mag. or less 2. Electron Microscope - non-living specimens - > 1,000 X mag. 3. Incubator – keep microbes warm for growth

Techniques of Microbiology Staining – to better see structures Microbial Culture - growing the tiny beasties Container for microbe culture - usually Petri dish Culture media Food for the microbes - E.g. Agar – (from red algae) - Others such as nutrient broths

Biological OrderedClassification When classification schemes were first developed, all living organisms could easily be placed in a general category, like Kingdom Plantae or Kingdom Animalia. General categories, such as Kingdoms still work well in classification but they break down when some organisms in one category have characteristics which are similar to organisms in another category. A case in point is the one-celled organism, Euglena, which bears both animal and plant characteristics.

Taxonomic categories

Depend on this classification; the Living Organisms is divided in to 3 Domains (1978 Carl Woese) 1. Bacteria Unicellular prokaryotes with cell wall containing peptidoglycan 2. Archaea Unicellular prokaryotes with no peptodoglycan in cell wall

3. Eukarya Protista Fungi Plantae Animalia

Depend on this classification, we can divide the Living Organisms in to 6 Kingdoms : 1. Animalia 2. Plantae 3. Fungi 4. Protista 5. Arcaebacteria 6. Eubacteria

Type of cells Prokariotic cells: bacteria and blue- green algae Eukariotic cells: fungi and protozoa Viruses: infective particle that need a viable cell for their replication and can be seen using EM

Procaryotes: relative simple morphology and lack true membrane defined nucleus

Eucaryotes: morphologically complex with a true membrane enclosed nucleus

viruses Since viruses are acellular and possess both living and nonliving characteristics, they are considered neither prokaryotic nor eukaryotic. They will be discussed in separate section of the course

Domain: Archaea Prokaryotic Lack peptidoglycan Often live in extreme environments Not known to cause disease in humans or animals Had been considered bacteria until examination of their unique rRNA sequences.

Includes: Methanogens Extreme halophiles Extreme thermophiles

Scope of Microbiology: Microbiology has an impact on medicine, agriculture, food science, ecology, genetics, biochemistry, immunology, and many other fields.

Many microbiologists are primarily interested in the biology of microorganisms, while others focus on specific groups; Virologists - viruses Bacteriologist - bacteria Phycologist – algae Mycologist -fungi Protozoologist – protozoa

Medical Microbiology: deals with diseases of humans and animals; identify and plan measures to eliminate agents causing infectious diseases. Agricultural Microbiology: impact of microorganisms on agriculture; combat plant diseases that attack important food crops.

Food and Dairy Microbiology: prevent microbial spoilage of food & transmission of food-borne diseases (e.g. salmonellosis); use microorganisms to make food such as cheeses, yogurts, pickles, beer, etc.

Industrial Microbiology: using microorganisms to make products such as antibiotics, vaccines, steroids, alcohols & other solvents, vitamins, amino acids, enzymes, etc.

Genetic Engineering: Engineered microorganisms used to make hormones, antibiotics, vaccines and other products.