1 HISTORY OF MICROBIOLOGY.pdf

REAN STAR PAULINE C. CORTINA, RMT  THE FIRST OBSERVATIONS Lucretius (98-55 B.C.) and Girolamo Fracastoro (1478-1553)  suggested that diseases were caused by “invisible living creatures” Francesco Stelluti (1577-1652)  made the earliest observations on bees and weevils using...

REAN STAR PAULINE C. CORTINA, RMT  THE FIRST OBSERVATIONS Lucretius (98-55 B.C.) and Girolamo Fracastoro (1478-1553)  suggested that diseases were caused by “invisible living creatures” Francesco Stelluti (1577-1652)  made the earliest observations on bees and weevils using a microscope supplied by Galileo Robert Hooke reported to the world that life's smallest structural units were "little boxes," or "cells," marked the beginning of the CELL THEORY--- all living things are composed of cells Hooke's Microscope (1665) Antonie van Leeuwenhoek was inspired by this publication Anton van Leeuwenhoek (1632-1723) considered as the “first true microbiologist” first actually to observe live microorganisms through the magnifying lenses of more than 400 microscopes he constructed wrote a series of letters to the Royal Society of London describing the "animalcules“ (tiny living and moving cells) he saw through his simple, single-lens microscope (50x to 300x) made detailed drawings of "animalcules" in rainwater, in his own feces, and in material scraped from his teeth üBacteria üProtozoa üSperm cells üBlood cells üMicroscopic worms  3-4” microscope  Required good lighting and patience  SPONTANEOUS GENERATION  believed that some forms of life could arise spontaneously from nonliving matter  toads, snakes, and mice could be born of moist soil; flies could emerge from manure; and that maggots, the larvae of flies, could arise from decaying corpses Aristotle (384-322 B. C.)  Mentioned that simple invertebrates could arise from Spontaneous Generation Francesco Redi (1626-1697) d e m o n s t r a t e t h a t m a g g o t s d i d n o t a r i s e spontaneously from decaying meat (1668) results of his investigation invalidated the long- held belief that life forms could arise from non- living things John Needham (1731-1781)  observed that a boiled mutton broth eventually became cloudy after pouring it into a flask that was then sealed tightly  found that even after he heated nutrient fluids (chicken broth and corn broth) before pouring them into covered flasks, the cooled solutions were soon teeming with microorganisms claimed that microbes developed spontaneously from the fluids  Asserted that organic matter possessed a “vital force” that could give rise to life Lazzaro Spallanzani (1729-1799)  suggested that microorganisms from the air probably had entered Needham's solutions after they were boiled  proposed that air carried microorganisms to the culture medium showed that nutrient fluids heated after being sealed in a flask did not develop microbial growth Anton Laurent Lavoisier (1743-1794)  showed the importance of oxygen to life  THEORY OF BIOGENESIS Rudolf Virchow (1821-1902)  challenged the case for spontaneous generation with the concept of Biogenesis: living cells can arise only from pre-existing living cells Theodor Schwann (1810-1882) Observed that no growth occurred in a flask that contained a nutrient solution after allowing the air to pass through a heated tube George Friedrich Schroder (1810-1885) and Theodore von Dusch (1824-1890)  Noticed that no growth occurred after allowing the air to pass through a sterile cotton wool placed on a flask of heat-sterilized medium Louis Pasteur (1822-1895) disproved the doctrine of spontaneous generation demonstrated that microorganisms are present in the air and can contaminate sterile solutions, but that air itself does not create microbes showed that microorganisms can be present in nonliving matter-on solids, in liquids, and in the air demonstrated conclusivel y that microbial life can be destroyed by heat and that methods can be devised to block the access of airborne microorganisms to nutrient environments form the basis of Aseptic Techniques Aseptic Techniques  techniques that prevent contamination by unwanted microorganisms, which are now the standard practice in laboratory and many medical procedures John Tyndall (1820-1893) Showed that dust carry germs that could contaminate a sterile broth Tyndallization  is a form of sterilization in the 19th century that uses moist heat for 3 consecutive days to eradicate vegetative cells and endospores Ferdinand Cohn (1828-1898) Discovered that there are bacteria that could withstand a series of heating and boiling because of heat resistant structures known as endospores  THE GOLDEN AGE OF MICROBIOLOGY (1857-1914) Fermentation and Pasteurization Theodor Schwann  stated that yeast cells are responsible for the conversion of sugars to alcohol Louis Pasteur found that microorganisms called yeasts convert the sugars to alcohol in the absence of air: FERMENTATION  Pasteur's solution to the spoilage problem was to heat the beer and wine just enough to kill most of the bacteria that caused the spoilage: PASTEURIZATION Charles Chamberland - bacterial porcelain filter (1884), and developed anthrax vaccine along with Pasteur.  Germ Theory of Disease Microorganisms might have relationships with plants and animals specifically, that microorganisms might cause disease ANTISEPTIC SYSTEM: Ignaz Semmelweis (1816-1865)  demonstrated that physicians, who at the time did not disinfect their hands, routinely transmitted infections from one obstetrical patient to another  demonstrated that routine handwashing can prevent the spread of disease Joseph Lister (1827-1912)  introduced the system of antiseptic surgery in Britain  applied the germ theory to medical procedures began treating surgical wounds with a phenol solution pioneered in promoting among surgeons handwashing before and after an operation, the wearing of gloves, sterilization of surgical instruments Robert Koch (1843-1910)  First to show irrefutable proof that bacteria indeed cause disease discovered Bacillus anthracis in the blood of cattle that had died of anthrax (1876) Discovered Mycobacterium tuberculosis (1882) f i r s t t o c u l t i v a t e b a c t e r i a o n b o i l e d potatoes, gelatin, meat extacts and protein  established a sequence of experimental steps for directly relating a specific microbe to a specific disease: Koch's Postulates Koch’s Postulate 1. The microorganism must be present in every case of the disease but absent from a healthy host 2. The suspected microorganism must be isolated from a diseased host grows in a pure culture 3. The same disease must be present when the isolated microorganism is inoculated into a healthy host 4. The same organism must be isolated again from the disease host Collaborators of Koch Fanny Hesse (1850-1934) suggested the use of agar, a solidifying agent, in the preparation of the culture media Julius Richard Petri (1852-1921) developed the Petri Dish, which is a circular glass or plastic plate for holding the culture media Martins Beijerink (1851-1931) and Sergei Winogradsky (1856-1953) developed the enrichment-culture technique and the use of selective media IMMUNOLOGY: ADVENT OF VACCINATION Edward Jenner (1749-1823)  embarked on an experiment to find a way to protect people from smallpox  introduced the concept of vaccination P hysicians in China immu n i z e d p a t i e n t s b y removing scales from drying pustules of a person suffering from a mild case of smallpox, grinding the scales to a fine powder, and inserting the powder into the nose of the person to be protected Louis Pasteur (1822-1895) and PierrePaul Emile Roux (1853-1933) Pasteur used the term vaccine for an attenuated culture both made a series of experiments to produced attenuated stains of bacteria prove that when attenuated strains are introduced into healthy host, the latter remains protected and healthy against the virulent agent Emil von Behring (1854-1917) prepared antitoxins for diphtheria and tetanus Elie Metchnikoff (1845-1916) first to described the immune system cells and the process of phagocytosis  THE BIRTH OF MODERN CHEMOTHERAPY: DREAMS OF A "MAGIC BULLET“ Chemotherapy  treatment of disease by using chemical substances chemical treatment of non-infectious diseases, such as cancer Antibiotics  chemicals produced naturally by bacteria and fungi to act against other microorganisms Synthetic drugs  chemotherapeutic agents prepared from chemicals in the laboratory  THE FIRST SYNTHETIC DRUGS Paul Ehrlich (1854-1915)  speculated about a bullet" that could hunt down and destroy a pathogen without harming the infected host  found a chemotherapeutic agent called Salvarsan (Arsphenamine), an arsenic derivative effective against syphilis Selman Waksman (1888-1973) discovered streptomycin and neomycin antibiotics regarded as “Father of Antibio t ics” by so m e historians  A FORTUNATE ACCIDENT- ANTIBIOTICS Alexander Fleming (1881-1955)  accidentally discovered Penicillin  mold was later identified as Penicillium notatum (later renamed Penicillium chrysogenum Howard Florey (1898-1968) and Ernst Chain (1906-1979) Made the purification process for penicillin and clinical trials to humans Edward Abraham (1913-1999)  First to propose the correct biochemical structure of Penicillin