UNIT-1-Introduction-to-Microbiology.pdf

Introduction to Microbiology SHAIRA DAWN G. OAQUERA Faculty, DBS  A What is Microbiology? E — study of microorganisms. — Micros “small”, bios “life”, logy “study of”...

Introduction to Microbiology SHAIRA DAWN G. OAQUERA Faculty, DBS  A What is Microbiology? E — study of microorganisms. — Micros “small”, bios “life”, logy “study of” B Microbes - biological entities that are too small to be F seen with our naked eye - ubiquitous in nature C Major groups: Bacteria, Algae, Protozoa, Helminths, and Fungi Viruses - noncellular; depend on cells for D G replication Why is Microbiology Important? The science of microbiology is about: microorganisms and how they work diversity and evolution of microbial cells Ecology Basic biological science Microbiology uses microbial cells to probe the fundamental processes of life (organization, metabolism and reproduction) Applied biological science Microbiology is at the forefront of many important breakthroughs in human and veterinary medicine, agriculture, and industry History: Notable Milestone in Microbiology Year Event 1676 Antonie van Leeuwenhoek saw and described bacteria & other microbes for first time 1799 Lazaro Spallanzani attempted to disprove theory of “Spontaneous Generation” 1861 Louis Pasteur demolished “Spontaneous Generation” 1866 Ernst Häeckel introduced Kingdom Protista and the terms “Ecology” & “Monera” 1883 Robert Koch developed method to isolate and culture bacteria 1887 Sergei Winogradsky developed the concept of chemoautotrophy Martinus Beijerinck characterized bacterial nitrogen and sulfur transformations; described his work 1905 as “Microbial Ecology”; discovered virus (infectious agent – TMV = Tobacco mosaic virus) 1929 Alexander Fleming discovered antibiotic penicillin & enzyme lysozyme 1953 James Watson & Francis Crick solved molecular structure of DNA 1980 Carl Woese described Archaea and proposed three domains of life 1985 Kary Mullis invented the Polymerase Chain Reaction (PCR) Craig Venter used genome sequencing to examine Sargasso Sea and identified 1.2 million previously 2004 unknown genes  Antonie van Leeuwenhoek brass plate biconvex “Father of Microbiology” and inventor of lens high-power microscopy specimen holder Crafted >200 microscopes (3-4” long, with only one lens yet with magnifying power >200x), but he kept secret the construction focusing screw methods In 1676, he first to see bacteria (he called them “wee animacules”) in the rain, seawater, snow, (1632-1723) and the scum on teeth Also described the green algae Chlamydomonas, Volvox, handle Spirogyra and Hematococcus, and ciliate Vorticella focusing screw For 50 years (1673-1723) sent thru an emissary of his findings in ~ 190 Letters with illustrations to the Royal Society of London replica of van for publication in the Philosophical Transactions of the Royal Leeuwenhoek’s microscope Society Leeuwenhoek’s Documentation Some of his Letters (A) & specimen packets (B) were found in 1981. Sample packets were re-examined with his own existing single- lens microscope Microspora (cyanobacterium) Tuber (truffle ascospores) spirillum (bacterium) erythrocytes (from capillaries) sperms  Theory of Spontaneous Generation “Life from non-life“, “De novo synthesis” “Living organisms spring forth from non-living materials” Beliefs based on untested interpretations of the world, e.g., -Observation: when meat rots, the flies abound -Conclusion: rotting meat gives rise to flies ARISTOTLE Jan Baptista van Helmont:  mice could arise from rags and wheat kernels decaying material could be transformed by the “spontaneous left in an open container for 3 weeks. action of Nature” into life. The theory held for 2 Millennia (2000 years) Theory of Spontaneous Generation Francesco Redi first to refute the idea that maggots spontaneously generate on meat left out in the open air  Louis Pasteur Disproving “Father of Microbiology and Immunology” Spontaneous Generation  Development of the germ theory of disease  Disproved “Spontaneous Generation”  Developed pasteurization “life only comes from life”  Treatment and prevention of rabies (immunization) - Louis Pasteur (1822-1895) His scientific approaches, intuition and breadth of accomplishment mark Louis Pasteur as a giant among scientists Pasteur’s Simple but Elegant Experiment to Disprove “De Novo Synthesis”  He made a series of flasks with long, twisted necks, or called “swan-neck” flasks  He boiled broth to sterilize it.  the twists and bends of the flasks’ necks prevented the introduction of any airborne microorganisms.  The Germ Theory of Disease Robert Koch  Discovered causative agents of tuberculosis (Mycobacterium tuberculosis) and cholera (Vibrio cholera)  Developed in 1881 simple and reproducible method of isolating microorganisms into pure cultures  Alexander Fleming  First antibiotic was ◄ E. coli discovered by accident ◄ Staphylococcus spent broth of Fleming’s ► Penicillium ◄Streptococcus  a clear area where bacterial Penicillium rubens ◄ Pneumococcus growth had been inhibited (= Chrysogenum ◄ Gonococcus encircled the mold notatum) ◄ B. influenzae "OneSir Fleming’s sometimes original 1928 assay method of crude finds what one extract of Penicillium is not looking for." Penicillium chrysogenum: the mold that inhibited the growth of a bacterium Penicillin: mold’s active inhibitor Paper on discovery of penicillin: Alexander Fleming, 1929. On the antibacterial action of cultures of a Penicillium, with special reference to their use in the isolation of B. influenzae. British J. Exp. Pathology 10: 226-236.  Classification of Microorganisms Acellular They are not cells and have no cell membrane. (infectious agents) Composed of few genes protected by a protein coat They can live and reproduce only when living inside a living cell Have no nucleus Pro – before, No membrane-bound Bacteria, Archaea, Prokaryotes cells without a organelles Cyanobacteria Less complex Cellular nucleus (microorganism) Eu – true Have true nucleus Eukaryotes cells that have Membrane-bound Algae, Protozoa & Fungi nucleus organelles More complex Properties of all cells Properties of some cells  Divisions of Microbiology -BACTERIOLOGY the study of BACTERIA Prokaryotic Do not contain nucleus or membrane-bound organelles The reproductive system is carried out through binary fission Thiomargarita namibiensis lives in mud on the African coast consumes hydrogen sulfide Escherichia Staphylococcus Oscillatoria  Divisions of Microbiology - MYCOLOGY the study of FUNGI Natural decomposers – secrete digestive enzymes to break down complex food sources Get nutrients by absorbing the organic material through symbiotic relationships such as with plants or a host Saccharomyces Aspergillus sp. Pleurotus sp. Lichen (Yeast) (Mold) (Mushroom) Common edible a symbiotic partnership Eukaryotic, single-celled plant pathogen mushroom of fungus and alga  Divisions of Microbiology - PROTOZOOLOGY the study of PROTOZOA Single-cell organisms which consist of a nucleus and complex organelles amebiasis Found in a variety of moist habitats such marine environments, fresh water and in soil Amoeba sp. Protozoal parasites transmitted by mosquitoes Paramecium sp. Euglena sp. (Ciliate) (Flagellate) Plasmodium sp. Free-living single cell flagellate eukaryotes \ (Sporozoa)  Divisions of Microbiology - PHYCOLOGY the study of ALGAE able to manufacture their food through the process of photosynthesis Can grow in places that have enough moisture They produce 75% or more O2 in the planet’s atmosphere Thalassionema sp. Volvox sp. Dinoflagellates (Diatom) (Green Algae) unicellular uni/multicellular unicellular Type of phytoplankton diverse group of algae source of red tides Divisions of Microbiology - HELMINTHOLOGY the study of PARASITIC WORMS large enough to be seen with the unaided eye cause a wide variety of infectious diseases God of Medicine  Divisions of Microbiology - VIROLOGY the study of VIRUSES The smallest type of microbes Consist of DNA or RNA in their nucleic acid core Wendell Stanley demonstrated TMV as different from other microbes, so simple and homogeneous that it could be crystallized like a chemical compound. Tobacco Mosaic Virus (TMV) TMV under Electron Microscope Discovered by Dmitry Ivanovsky Divisions of Microbiology - VIROLOGY Viruses are not found on the tree of life - not truly alive. Viruses are obligate (require) parasites that can only replicate within the cytoplasm of a host cell. ARCHAEA Oxidizes sulfur to sulfate, while fixating carbon from carbon dioxide Sulfolobus acidocaldarius Facultative autotroph Post-assessment Microbial Applications Shaira Dawn C. Galacgac  Are microbes good or bad? Small percentage (