BIOL2010 Microbiology - University of Doha PDF

BIOL2010 Microbiology Unit 1: Introduction to Microbiology 1. Why do YOU need this course? 2. What does the term Microbiology mean? 3. How is Microbiology related to your field of study? History of Microbiology In science courses, students often wonder the purpose of studying history? Studyi...

BIOL2010 Microbiology Unit 1: Introduction to Microbiology 1. Why do YOU need this course? 2. What does the term Microbiology mean? 3. How is Microbiology related to your field of study? History of Microbiology In science courses, students often wonder the purpose of studying history? Studying history is useful because it allows one to understand logic applied by past scientists to solve problems of their era. No matter what time frame, seeing examples of logic & learning from them can help to boost your own problem solving abilities. Microbiology Timeline Antonie Van Leeuwenhoek (1623-1732) During time of AVL scientists thought tiny organisms existed everywhere, some which likely caused diseases (e.g. the plague) So if tiny animals were invisible to naked eye - what is next logical step in being able to study them? Invent a tool that will allow one to see them. AVL was first person to invent a lens to be used for Studying microorganisms. AVL Animacules – ‘Tiny animals’ Discovered organisms in the oral plaque of his and others teeth. First to describe blood cells, sperm cells and many, many microorganisms, bacteria, protists and fungi. Edward Jenner (1749 – 1823) Considered the father of immunology. Pioneered the concept of vaccines. Discovered the smallpox vaccine. His work is believed to have helped to save more lives than any other human. Louis Pasteur (1822-1895) The ‘father of bacteriology’, ‘the father of microbiology’ Chemist and microbiologist involved in the study of fermentation, spontaneous generation, vaccines and bacteriology. Developed vaccines for Anthrax and rabies. Pasteurization. Robert Koch (1843 – 1910) Father of medical bacteriology. Koch’s Postulates. Germ Theory of Disease. Pioneered culturing and microbiology laboratory techniques. Discovered the bacteria that causes diseases such as: Cholera, Tuberculosis, Anthrax and Septicemia. Robert Koch (1843 – 1910) Koch’s Postulates Invaluable in their day to determine the cause and effect of bacterial diseases. No longer always reliable as we discover modern molecular techniques, and genetic markers. Ignaz Semmelweis (1818 – 1865) Contributed to the promotion of sanitation in hospitals. Demonstrated that disease could be reduced through hand washing. Made doctors and students wash hands with a chlorinated solution between dissections and patients. This dropped the mortality rate in the maternity ward at his hospital to less than 1%. Joseph Lister (1827 - 1912) Father of aseptic surgery Used carbolic acid (Phenol) to wash surgical instruments, hands, and air. This prevented infection and complications due to surgery. John Snow (1813 – 1858) The first to conduct epidemiologic studies. Traced the course of a cholera epidemic in London in 1854. His studies prevented further infections. Also a leader in anesthesia in the UK as well as medical hygiene. Florence Nightingale (1820 – 1910) Established nursing as an art and science. Distinguished nursing from medicine. Identified personal needs of patients and the role of nurses to meet them. Established standards for hospital management. Established nursing education and nursing as a respected occupation for women. Paul Ehrlich (1854 – 1915) Father of Chemotherapy. Worked in hematology, immunology, and antimicrobial chemotherapy. Developed methods for staining tissue. Developed Salvarsan, the first effective medicinal treatment for syphilis. The magic bullet. Alexander Fleming (1881 – 1955) Discovered that bodily fluids could have antimicrobial properties – Lysozyme. Discovered the first widely used antibiotic - Penicillin. Serendipity. Willoughby Miller (1853 – 1907) Dentist and the first oral microbiologist. First to discover that caries are the results of bacterial metabolism. Chemicoparasitic Theory. Carl Woese (1928 – 2012) Studied bacterial genetics. Discovered that hot spring bacteria in Yellowstone National Park had very different genomes than any other organisms on earth. Discovering the Archaea. Proposed the Three Domain System of classification. Microscopy Microorganism Size Comparison Different types of microscopes and microscopy Bright field Dark field Phase contrast Fluorescence Electron microscopy Light Microscopy Any microscope that uses visible light to function: - Bright field: Simplest form, light illuminates the entire specimen and field. Has a light background. - Dark field: Light is prevented from directly illuminating the field. Has a dark background. Used for specimens that need extra contrast. Light microscopy Phase contrast: Used to observe living organism. Special condenser and objective lenses detect small differences in refractive indices of cell structures which results in contrast. Fluorescence: UV light is used to strike the specimen, excite molecules and express a longer wavelength which can appear bright. Electron Microscopy Instead of using light, electron microscopes use a beam of electrons. Instead of using lenses to focus the light, EM’s use magnets in a vacuum to direct the electrons and allows for a much higher resolution and as a result much higher magnifications. Electron microscopy Transmission Electron Microscope (TEM): Resolution down to 1 nm, and magnification up to 500,000x. Specimens are imbedded in plastic and cut into thin sections. Needs to be thin so that the beam of electrons, which has poor penetration, can pass through the specimen. Electron Microscopy Scanning Electron Microscope (SEM): Images the surface of specimens, resolution down to 20 nm, and magnification up to 50,000x. Specimens are coated in a heavy metal, and a beam of electrons are scanned over the surface, reflected electrons are captured and the image is displayed on a screen. Electron Microscopy