INTRODUCTION TO • Described bacteria and protozoa in dirty water
MICROBIOLOGY • Hungarian gynaecologist
• Recommended hand washing before clinical examinations
which was met with disdain
• Died in psychiatric hospital in 1865
• It is the study of very small (microscopic) things
• Father of infection control and prevention
• Interest in what causes spoilage and disease started many
years ago, it was thought to be spontaneous or caused by
‘bad air’ or ‘germs’
• Several prominent scientists played an important role over • French chemist who studied yeasts used to make wine
the years from grape juice
• ‘Bad’ wine is the result of incorrect yeasts (actually
bacteria)
• Basic principles of immunology
• Laid foundation of biochemical and industrial microbiology
• Published on contagion (first exposition of germ theory)
• First to discover penicillin (publication is lost)
• Wrote a poem giving syphilis its name
• Pasteur developed a vaccine against anthrax and rabies
• Italian doctor
• German doctor
• In 1665 he discovered worms in rotten meat are fly larvae
• First person to develop staining technique for
microorganisms
• First to photograph bacteria under the microscope
• Dutch tradesman and scientist from Delft, Netherlands
• German school under leadership of Koch (emphasis on
• Handcrafted microscopes, magnify between 50-300 X and
isolation, culture, and characterisation of microorganisms)
observe and describe single celled organisms
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,• Advocated the use of phenol as disinfectant in 1860 • In 1866 Haeckel classified microorganisms separately
• Modern era of aseptic surgery born from plants and animals in a third kingdom namely Protista
• Lower Protista (prokaryotes: bacteria, blue green algae,
mycoplasmas, Rickettsia, Chlamydia)
• Russian zoologist • Higher Protista (eukaryotes: protozoa, algae, slime fungi
• Received Nobel prize in 1908 for his work on principles of and fungi)
cellular immunity • Haeckel’s classification of the world
• Whittaker’s five kingdom classification of all living things
• Woese’s phylogenetic tree (of course, with advances in
• Discovery of streptomycin in 1944 science and technology, new and improved classifications
have emerged e.g. eubacteria (including all human
bacterial pathogens) and archaebacteria (including special
• Vaccine against yellow fever bacteria surviving in hydrovents, thermal springs) and
eukaryotes form distinct clades)
• Infectious diseases caused by five groups (bacteria,
• Polio vaccine in 1951 viruses, helminths, fungi, and protozoa)
• Helminths: complex multi-cellular organisms (metazoan)
• Helminths and protozoa are parasites
• DNA helix structure in 1959 • Viruses differ from other organisms (not independent and
• Mechanism of DNA replication, gene function and cell can only replicate within other cells)
division
• Discovery of sexual process in bacteria led to birth of
molecular biology
• DNA transfer between mating bacteria (conjugation)
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, diameter, while eukaryotic cells range from 10 to 100 μm
in diameter
• Eukaryotic cells have a nucleus, a membrane-bound
chamber where DNA is stored, while prokaryotic cells do
not (feature that formally separates the two groups)
• Eukaryotes have other membrane-bound organelles in
addition to the nucleus, prokaryotes do not
• Cells in general are small, but prokaryotic cells are really
small (typical prokaryotic cells range from 0.2 to 2 μm in
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, • Plasmid is smaller, circular, extra-chromosomal DNA
• Three basic forms (coccus, bacillus, and spirillum)
• Arrangement determined by orientation and degree of
attachment of bacteria during cell division
• Size is 0.2 to 5 μm
• Coccus in pairs (diplococci) • Storage of reserve metabolites
• Chains (streptococci) • Inorganic phosphate in the form of metachromatic
• Bunches (staphylococci) granules which stain red with blue dye
• In cytoplasm where protein synthesis occurs
• Phospholipids and protein
• Infoldings in the membrane known as mesosomes
• Two types (septal and lateral mesosomes)
• Bacterial chromosome attached to septal mesosome
• Chromosome is a single double-stranded circular DNA
• Chromosome is linked to mesosome (NB for cell division)
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