Basic Microbiology - Introduction to Microbiology

Basic Microbiology Chapter one: Introduction to Microbiology  - Microbiology Microbiology is the study of microorganisms, a large and diverse group of microscopic organisms that exist as single cells or cell clusters....

Basic Microbiology Chapter one: Introduction to Microbiology  - Microbiology Microbiology is the study of microorganisms, a large and diverse group of microscopic organisms that exist as single cells or cell clusters. The group includes: 1. Bacteria - Bacteriology ~ 2. Fungi (yeasts and molds) - Mycology B %** S 3. Protozoa, and microscopic algae – Parasitology , - Phycology 4. Viruses - Virology  L Microbes in Our Lives… pathogenic or non-pathogenic pathogenic B r * The microorganisms, germs or microbes? Germ actually comes from the Latin word germen, meaning to spout from, or germinate it was first used in relation to microbes in the nineteenth century to explain the rapidly growing cells that caused disease. Microbes are minute living things that individually are usually too small to be seen with the unaided eye. The group includes bacteria, fungi (yeasts and molds), protozoa, and microscopic ji5 algae. It also includes viruses, those noncellular entities - sometimes regarded as straddling the border between life and nonlife  ~ …Microbes in Our Lives Importance of microbes 1. Microorganisms are important in maintaining Earth’s ecological balance (photosynthesis). 2. Some microorganisms live in humans and other animals and are needed to maintain good health (synthesis some of B vitamins) – Microbiota. (trillions of microbes) > - Swiss cheese (i) ↑ 3. Some microorganisms are used to produce foods and chemicals (vitamins, organic acids, enzymes, alcohols). 99 4. Some microorganisms cause disease (Tuberculosis).  History of microbiology… In 1665, X after observing a thin slice of cork through a crude microscope, Englishman Robert Hooke reported that life’s smallest structural units were “little boxes,” or “cells.” Hooke’s discovery marked the beginning of the cell theory— the theory that all living things are composed of cells Anton van Leeuwenhoek observed live microorganisms through the magnifying lenses of the more than 400 microscopes he constructed Between 1673 and 1723 as shown in figure 1.  - …History of microbiology… X The period from# 1857 to 1914 has been appropriately named first golden age of Microbiology In 1861 Louis Pasteur demonstrated that microorganisms are present in the air and can contaminate sterile solutions, but that air itself does not create microbes. He filled several short-necked flasks with beef broth and then boiled their contents. Some were then left open and allowed to cool. In a few days, these flasks were found to be contaminated with microbes (figure 3).  Figure 3: Pasteur’s experiment pasteur dipate i · the theory ? ~ j25 kills the microorganisms * Boiling  Golden Stages in Microbiology… - ~ 3 -. 1. Fermentation and Pasteurization: Fermentation: Pasteur found that yeasts ferment sugars to alcohol and that bacteria can oxidize the alcohol to acetic acid. Pasteurization: heating process used to kill bacteria in some alcoholic beverages and milk. 2. The Germ Theory of Disease: Robert Koch proved that microorganisms cause disease. He used a sequence of procedures, now called Koch’s postulates (1876), that are used today to prove that a particular microorganism causes a particular disease.  ~ …Golden Stages in Microbiology… 3. Vaccination: - In 1798, Edward Jenner demonstrated that inoculation with S cowpox material provides humans with immunity to S,? smallpox. About 1880, Pasteur discovered that a virulent bacteria could be used as a vaccine for fowl cholera. antibiotic chemotherapy , g 4. Antimicrobial agents birth: Paul Ehrlich introduced an arsenic-containing chemical called salvarsan to treat syphilis (1910) - chemotherapy. Alexander Fleming observed that the Penicillium fungus inhibited the growth of a bacterial culture. He named the active ingredient penicillin (1928) - antibiotics.  …Golden Stages in Microbiology… 3 In 1910, Paul Ehrlich found a chemotherapeutic agent called salvarsan, an arsenic derivative effective against syphilis, By the late 1930s sulfonamides (sulfa drugs) were synthesized at about the same time. X 5. Molecular Genetics: Microbial genetics studies the mechanisms by which microorganisms inherit traits, and molecular biology looks at how genetic information is carried in molecules of DNA. In the 1950s, James Watson and Francis Crick proposed a model for the structure and replication of DNA. In the early 1960s, François Jacob and Jacques Monod discovered messenger RNA.  …Golden Stages in Microbiology… & :s ~ 6. Microbes and Human Welfare: Recycling Vital Elements: bacteria converting chemical element such as carbon, nitrogen, oxygen, sulfur, and phosphorus into forms that plants and animals can use. Sewage Treatment: using bacteria to convert organic material into such by-products as carbon dioxide, nitrates, phosphates, sulfates, ammonia, hydrogen sulfide, and methane. Bioremediation using microbes: toxins can be removed from underground wells, chemical spills, toxic waste sites, and oil spills.  …Golden Stages in Microbiology… -X 7. Biotechnology and Recombinant DNA Technology: Commercial use of microorganisms to produce some common foods and chemicals. Biotechnology has undergone a revolution by expand the potential of bacteria, viruses, and yeast and other fungi as small biochemical factories. Cultured plant and animal cells, as well as intact plants and animals, are also used as recombinant cells and organisms.. Gene therapy: by inserting a missing gene or replacing a defective one in human cells. X…Golden Stages in Microbiology… X …Golden Stages in Microbiology…  - Microorganisms and human body… intestine small sin mucus membrane , large , lacrimal gland ji? , - , oral cavity - Normal microbiota: microorganisms on and inside our bodies making up our normal flora (figure 4). Role of microbiota (normal flora) in human body: 1. Protect us against disease by preventing the overgrowth of harmful microbes 2. Produce useful substances such as vitamin K and some B vitamins 3. Under some circumstances normal microbiota can make us sick or infect people we contact : 59 50 % %145616 !* -  …Microorganisms and human body… Biofilms - Microorganisms may exist as: 1. Single cells that float or swim independently in a liquid 2. Attach to each other and/or some usually solid surface Biofilm: Bacterial communities that form slimy layers on surfaces (figure 5) Biofilm role: 1. Protect our mucous membranes from harmful microbes. 2. Cause infections as endocarditis or clog medical implants (catheters). 3. Play role in antibiotic resistance (protective barrier). X  …Microorganisms and human body… / & Infectious Diseases: a disease in which pathogens invade a susceptible host, such as a human or an animal, the pathogen carries out at least part of its life cycle inside the host, and disease frequently results (e.g. malaria). Emerging infectious diseases (EIDs):new or changing disease showing an increase in incidence in the recent past or a potential to increase in the near future. Factors contributed to the development of EIDs: :, taking *T 1. Evolutionary changes in existing organisms (e.g.,Vibrio cholerae) 2. The spread of known diseases to new geographic regions or populations by modern transportation (e.g., West Nile virus) 19 …Microorganisms and human body 3. Increased human exposure to new, unusual X infectious agents in areas that are undergoing ecologic changes (e.g., Venezuelan hemorrhagic virus, H1N1 influenza, SARS). 3. Antimicrobial resistance (e.g.,vancomycin-resistant S. aureus)  - Classification of microorganisms Before the existence of microbes was known, all organisms were grouped into either the animal kingdom or the plant kingdom. In 1978, Carl Woese devised a system of classification based on the cellular organization of organisms as follows: 1. Bacteria (cell walls contain a protein–carbohydrate complex called peptidoglycan) 2. Archaea (cell walls, if present, lack peptidoglycan) 3. Eukarya, which includes the following: I. Protists (slime molds, protozoa, and algae) II. Fungi (unicellular yeasts, multicellular molds, and mushrooms) III. Plants (mosses, ferns, conifers, and flowering plants) IV. Animals (sponges, worms, insects, and vertebrates)  - Nomenclature of microorganisms It was established in 1735 by Carolus Linnaeus Scientific names are latinized Scientific nomenclature assigns each organism two names: 1. Genus (plural: genera) is the first name and is always capitalized. 2. Specific epithet (species name) follows and is not capitalized. See table one for examples  X Table 1: Examples for microorganisms' scientific names Scientific name Source of Genus Name Source of Specific Epithet Honors public health Salmonella enterica Found in the intestines microbiologist (bacterium) (entero-) Daniel Salmon Is.35 Do Streptococcus pyogenes Appearance of cells in chains Forms pus (pyo-) (bacterium) (strepto-) 55 9 , - - : - Saccharomyces cerevisiae Fungus (-myces) that uses sugar Makes beer (cerevisia) (yeast) (saccharo-) 9939.. Penicillium chrysogenum Tuftlike or paintbrush (penicill-) Produces a yellow (chryso-) (fungus) appearance microscopically pigment -% 1995. Trypanosoma cruzi Corkscrew- (trypano-, borer; Honors epidemiologist (protozoan) soma-, body) Oswaldo Cruz