Bacteria and protozoa – were thefirst microorganisms observed byhumans It took 200 years before man wasable to establish a connectionbetween microorganism andinfectious disease. It was the discovery of microscopethat made microbiology understandmore about the nature of diseases.
Anton van Leeuwenhoek – wasthe first person to see livebacteria and protozoa Father of microbiology A fabric merchant, surveyor,wine assayer, and a minor cityofficial in Delf, Holland Ground tiny glass lensesmounted in metal frames Single lens microscopes “Animalcules”
Scrapings from teeth Ditches and pond water Blood and sperm Diarrheal stool
A French chemist Fermentation Grapes (glucose)-yeasts-ethanol Disproved the spontaneousgeneration Aerobes and anaerobes Developed the processpasteurization to kill microbes thatwere causing to spoil. Can be usedto kill pathogens in many types ofliquids. Involves heating to 55 degreecelsius and holding at thattemperature for several minutes.
He discovered the infectious agents that causedthe silkworm diseases that were crippling thesilk industry in France. Germ theory of disease- made contributions thata certain microorganism can cause a certaindisease. Hospital practices to minimize the spread ofdisease by pathogens Developed vaccines to prevent chicken cholera,anthrax, and swine erysipelas Developed the vaccine to prevent rabies in dogsand successfully used the vacine to treat humanrabies
German physician Contributor to the germ theoryof disease He proved that anthraxbacillus was truly the cause ofanthrax. Koch’s postulate Discovered that a. bacillusproduces spores capable ofresisting adverse conditions Fixing and staining andphotographing bacteria
Developed methods of cultivating bacteria onsolid media. R.J. Petri- colleague of robert Frua hess- agar (polysaccharide)as solidifyingagent Dicovered mycobacterium tuberculosis andvibrio cholera
Spontaneous generation– abiogenesis Classical notions ofabiogenesis, now moreprecisely knownas spontaneousgeneration, held thatcertain complex, livingorganisms aregenerated by decayingorganic substances.
John tyndall and Louis Pasteur – were the onewho disproved the abiogenesis theory. Rudolf Virchow – was the first who proposedabout biogenesis
A microorganism must be found in all cases ofthe disease and must not be present in healthyanimals or humans. The microorganism must be isolated from thediseased animal or human and grown in pureculture in the laboratory. The same disease must be produced whenmicroorganisms from the pure culture areinoculated into healthy susceptible laboratoryanimals The same microorganism must be recoveredfrom the experimentaly infected animals andgrown again in pure culture
Exeptionshave to grow the pathogen in amedia but not all can grow (viruses,rickettsiasSome pathogens are species-specificSynergistics –caused by more than oneorganismLess pathogenic when cultured
In the late 1800s and for the first decade of the1900s, scientists seized the opportunity tofurther develop the germ theory of disease asenunciated by Pasteur and proved by Koch. There emerged a Golden Age ofMicrobiology during which many agents ofdifferent infectious diseases were identified.Many of the etiologic agents of microbial diseasewere discovered during that period, leading tothe ability to halt epidemics by interrupting thespread of microorganisms.
Despite the advances in microbiology, it wasrarely possible to render life-saving therapy toan infected patient. Then, after World War II,the antibiotics were introduced to medicine.The incidence of pneumonia, tuberculosis,meningitis, syphilis, and many other diseasesdeclined with the use of antibiotics.
Work with viruses could not be effectivelyperformed until instruments were developed tohelp scientists see these disease agents. In the1940s, the electron microscope wasdeveloped and perfected. In that decade,cultivation methods for viruses were alsointroduced, and the knowledge of virusesdeveloped rapidly. With the development of vaccines in the 1950sand 1960s, such viral diseases as polio, measles,mumps, and rubella came under control.
Modern microbiology reaches into many fields ofhuman endeavor, including the development ofpharmaceutical products, the use of quality-control methods in food and dairy productproduction, the control of disease-causingmicroorganisms in consumable waters, and theindustrial applications of microorganisms. Microorganisms are used to produce vitamins,amino acids, enzymes, and growth supplements.They manufacture many foods, includingfermented dairy products, as well as otherfermented foods such as pickles, sauerkraut,breads, and alcoholic beverages.