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Explore the fascinating history, classification, and physiology of microorganisms in this engaging lecture series by Prof. O. Pokryshko. Learn about the significant contributions of key figures like Leeuwenhoek, Pasteur, Koch, and more. Discover the relevance of studying microbiology for vaccines, antibiotics, biotechnology, and beyond. Uncover the different groups of microorganisms and their characteristics, from bacteria to viruses. Examine the developments in microbiology research and the impact on modern healthcare practices. Dive into the world of bacteria identification and classification, understanding their structures and functions. Join us in unraveling the intricate microbial world that shapes our daily lives.
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Chair of Medical Biology, Microbiology, Virology, and Immunology THE HISTORY OF MICROBIOLOGY. CLASSIFICATION AND STRUCTURE OF MICROORGANISMS.THE PHYSIOLOGY OF MICROORGANISMS. Lecturer As. Prof. O. Pokryshko
Lecture schedule • History of Microbiology. • Classification of bacteria. • Structure of bacterialcell • The physiology of microorganisms.Growth, reproduction and respiration of bacteria.
Why Study Microbiology? • Pharmaceuticals • Vaccines/Antibiotics • Biotechnology • Bioremediation • Pathogenicity • Fundamental Biology
MicrobiologyThe study of microorganisms • Microorganisms living things too small to be seen with the unaided eye • Microorganisms = Microbes
Microorganisms Divided into six groups • Bacteria • Archae • Algae • Fungi • Protozoa • Viruses
History of Microbiology • Microbes discovered >300yrs • Known to man during the mid 1800s • Period of progress began & continues to the present
Periods of microbiology development • Morphologic • Physiologic • Prophylactic
Morphological period inmicrobiology history (XVII middle of age). It is also called micrographycal period, as the study of microorganism came only to description of their dimensions and forms. Biological properties and their significances for man still a long time remained incomprehensible.
Experimental phase • Leeuwenhoek • Pasteur • Koch • Lister
Before 17th century, study of microbiology was hampered by the lack of appropriate tools to observe microbes. • Robert Hooke: In 1665 built a compound light microscope and used it to observe thin slices of cork. Coined the word cell. • Anton van Leeuwenhoeck: In 1673 was the first person to observe live microorganisms which he called “animalcules” (bacteria, protozoa), using single-lens microscopes that he designed. He observed 50,000 different specimens, reported findings to the Royal Society of London
Pasteur’s Contributions: • Pasteurization: Developed a process in which liquids are heated (at 65oC) to kill most bacteria responsible for spoilage. • Disease Causes: Identified three different microbes that caused silkworm diseases. • Vaccine: Developed a vaccine for rabies from dried spinal cords of infected rabbits. • Directed Pasteur Institute until his death in 1895.
Joseph Lister (1859): Used disinfectant to treat surgical wounds, greatly reducing infection rates. Considered the father of antiseptic surgery.
Robert Koch (1876): • First person proved that microorganisms caused diseases • Only specific microorganisms caused specific diseases • Studied anthrax affects cattle & humans • Proved that Bacillus anthracis causes anthrax in cattle. • Later identified bacterium that causes tuberculosis.
Study of viruses • Iwanoski (1892) studying diseases of tobacco plants • Discovered TMV • Filterable viruses
Prophylactic periodAfter 1914 Classic Metchnikov's researches defineda prophylactic periodinmicrobiology history. The Patriarch of world and Ukrainian microbiology - I. Metchnikov
Paul Ehrlich (1910): Search for “magic bullet”. • Discovered salvarsan, an arsenic derivative, was effective against syphilis. (1st synthetic drug to come in to widespread use) • Alexander Fleming (1928): Discovered that penicillin produced by the mold Penicillium notatum was able to prevent microbial growth. • Penicillin came into use 10 yrs later -By the 1940s known as the “wonder drug” • Rene Dubos (1939): Discovered two antibiotics (gramidin and tyrocidine) produced by bacterium (Bacillus brevis).
Classifications system. Bergey's Manual of Determinative Bacteriology – the "bible" of bacterial taxonomy. There are such levels of microorganisms’ organization: Species – Genus – Family – Class – Division – Kingdom
35 of the major groups of bacteria are distinguished primarily on morphological characteristics, namely: cell shapes (rods, cocci, curved, or filament forming); spore production; staining reactions; motility. Other groups are defined based on their metabolism, or combinations of morphological and physiological characteristics.
Some of the Major Groups of Bacteria in Bergey's Manual
Bacteria (Sing. Bacterium) • Small, single-celled (unicellular) organisms. • Procaryotes: “Before nucleus”. Lack the following structures: • Nuclear membrane around DNA • Membrane bound organelles • Mitochondria • Chloroplasts • Golgi apparatus • Endoplasmic reticulum • Lysosomes
Bacterial Identification and Classification • Shape - cocci, bacilli, spiral • Arrangement - single, pairs, chains, clusters • Size • Gram-positive vs. Gram-negative • Aerobic vs. anaerobic • Physical/structural characteristics • Biochemical characteristics • DNA analysis
The Dimension of Bacteria Relative size of a bacterial cell compared to other cells including viruses.
Coccus - round Bacillus - rod - Fusiform, coccobacilli Spirillum - corkscrew - Flexible, undulating - spirochetes - Curved - vibrios Gross morphology of bacteria • Size - 1 to 10 mm - aids in identification • Shape
Coccus Tetrad Diplococcus Sarcinae Streptococcus Staphylococcus Cocci groupings
Chains of cocci Streptococcus pyogenes
Clusters of cocci Staphylococcus aureus Sputum smear
Bacillus shaped bacteria Pseudomonas aeruginosa Escherichia coli
Bacillus shaped bacteria Fusobacterium
Bacillus chains Bacillus anthracis
Palisades arrangement Corynebacteriumdiphtheriae
Curved bacteria Vibrio cholerae Campylobacter
Curved bacteria Spirilla Borrelia burgdorferi
Cell Envelope • Cytoplasmic membrane • Cell wall Cell wall-less bacteria • No peptidoglycan layer • Cell membrane contains sterols for stability Mycoplasma pneumoniae
Cytoplasmic Membrane • Phospholipid bilayer • “Fluid mosaic” model • Embedded proteins for active transport • Enzymes for energy generation • Photosynthetic pigments
Cell membrane Peripheral Membrane Protein Phospholipid Integral Membrane Protein Peripheral Membrane Protein
Function of Cytoplasmic Membrane • Selective permeability to different molecules. • Active transport aided by permease. • Play a role in DNA replication. • Cell wall biosynthesis. • Mesosomes ----- cell division.