Introduction to Microbiology

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Introduction to Microbiology

• Module 1

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1.1 The Science and History of Microbes

• What is microbiology?
• Microbes are ubiquitous
• Pathogens and Non-pathogens
• Why study microbiology?
• Indigenous microflora clinical importance
• Food Production
• Bioremediation
• Biotechnology

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Causes of Disease

• Infectious Disease pathogen colonizes the body
  and subsequently causes disease
• Microbial Intoxication person ingests a toxin
  that was produced by a microorganism

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Subdivisions in Microbiology

• Prokaryotic
• Bacteria
• Archaea
• Eukaryotic
• Algae
• Fungi
• Protozoa

• Acellular
• Virus
• Viroid
• Prion

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Pioneers of Microbiology

• 1674 Anton van Leeuwenhoek
• 1796 Edward Jenner
• 1847 Ignaz Semmelweis
• 1853 John Snow
• 1857, 1861, 1864, 1881, 1885 Louis Pasteur
• 1867 Joseph Lister
• 1876, 1881, 1884 Robert Koch

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Pioneers of Microbiology

• 1884 Christian Gram
• 1904 Paul Ehrlich
• 1928 Frederick Griffith
• 1929 Alexander Fleming
• 1944 Avery, MacLeod, McCarthy
• 1948 Barbara McClintock
• 1953 Watson, Crick, Franklin, Wilkins

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Earliest Known Infectious Diseases

• Tuberculosis, Israel 7000 B.C.
• Pestilence, Egypt 3180 B.C.
• Smallpox, China 1122 B.C.
• Plague, Rome 800-430 B.C. (4 outbreaks)
• Syphilis, Europe 1500 A.D.

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Germ Theory

• Germ theory microorganisms can cause disease
• Spontaneous generation the idea that life can
  arise from non-living
• Biogenesis life can only arise from living
  organisms
• Pure culture a laboratory culture containing
  only a one single species of organism

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Kochs Postulates

• Postulates
• -Microbes must be present in diseased, not
  healthy organisms
• -Isolate grow organism in pure culture
• -Inoculate healthy organism with pure culture,
  organism will develop the disease
• -Recover same microbe from experimentally
  infected organism and grow again in pure culture

• Exceptions
• -Some microbes will not grow in vitro
• -Obligate intracellular pathogens can only
  survive and multiply within living host cells
• -Some pathogens ONLY infect humans and therefore
  can not be inoculated into other animals for
  testing
• cell culture models
• 4 Some diseases are caused by synergistic
  infection

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Microbiology Today

• Chemotherapy
• Antibiotics
• Synthetic drugs
• Immunology
• Study of disease and the bodys response to it
• Virology
• Study of viruses and viral diseases

• Basic Biology
• Using microorganisms to study metabolism and
  genetic properties similar to plants and animals
• Genetic Engineering
• Genomics
• Recombinant DNA technology

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Careers in Microbiology

• Microbiology Subdivisions
• Bacteriologist (bacteria)
• Phycologist (algae)
• Protozoologist (protozoa)
• Mycologist (fungi)
• Virology
• Immunologist
• Biotechnologist

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1.2 Molecules Metabolism Review

• Macromolecules
• Carbohydrates
• Lipids
• Protein
• Nucleic Acid

• Atoms
• Bonding
• Polar and nonpolar molecules
• Chemical reactions
• Solvents Solutes
• Acids Bases, pH
• Organic molecules

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Basic Chemistry Atoms

• Atoms the smallest component of an element,
  having properties of that element
• Nucleus
• Protons ()
• Neutrons (0, no charge)
• Outer shell
• Electrons (-)
• Elements matter composed of a single type of
  atom

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Basic Chemistry Bonding

• Chemical bonds form because of interaction of the
  electrons
• Covalent bonds
• Atoms share pairs of electrons strongest
• Ionic bonds
• Atoms complete their outermost shell by gaining
  or losing electrons and are then attracted to
  each other because of opposing charges
• Hydrogen bonds
• Hydrogen atoms interact with two or more parts of
  another molecule weakest but vitally important
  for life

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Covalent Bonds

• Polar Molecules
• Covalent bond in which shared electrons are not
  equally spaced
• Example water

• Nonpolar Molecules
• Covalent bond in which shared electrons are
  equally spaced
• Example ethane

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Chemical Reactions

• Atoms or molecules making or breaking chemical
  bonds
• Energy is required
• Endothermic- energy captured and used
• Exothermic- energy produced and released
• Activation energy
• Rate of reaction

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Solvents and Solutes

• Solution molecules dispersed in liquid
• Solute molecules that are dispersed
• Solvent liquid component of solution
• Example NaCl (table salt) dissolving in water.
• NaCl is the solute
• Water is the solvent

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Acids, Bases, and pH

• Pure water neutral, equal H and OH-
• Acids contain more H than OH-
• Bases contain more OH- than H
• pH is based on the concentration of H
• Range 0 to 14
• 0 is the most acidic
• 7 is neutral
• 14 most basic (alkaline)

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Organic Molecules

• Contain carbon (C) and hydrogen
• Carbon can form 4 bonds which makes it very
  versatile
• Complex structures
• Linear
• Branched
• Rings
• Basis of the macromolecules
• Carbohydrates, lipids, protein, nucleic acid

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Carbohydrates

• Carbon and water (CH2O)
• Monosaccharides (single sugars, monomers)
• Glucose, fructose, ribose, deoxyribose
• Glucose is the building block for many
  polysaccharides
• Disaccharides (two sugars)
• Sucrose, lactose
• Polysaccharides (many sugars, polymers)
• Glycogen, cellulose, amylose
• Functions
• Energy, building blocks

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Lipids

• Fatty Acids (FAs)
• Long non-polar chains of carbon and hydrogen
• Monomer for most lipids
• Saturated or Unsaturated
• Triglycerides
• Common as dietary fat
• Phospholipids
• Component of biological membranes
• Steroids Cholesterol
• Important in cell signaling and membranes
• Functions
• Energy and energy storage, cell signaling,
  membranes

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Proteins

• Amino Acids (monomers)
• Peptides
• Proteins
• Functions
• Enzymes
• Structural components
• Cell movement
• Carrier molecules

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Nucleic Acids

• Nucleotides (monomers)
• Deoxyribose (DNA) or Ribose (RNA)
• Base (A,C,G and T or U)
• Phosphate groups
• DNA and RNA Functions
• Genetic information
• Nucleotides as energy molecules
• Assembly of proteins

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Products of Metabolism

• Water
• Energy production
• CO2
• Changes in pH
• Acid and Base

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1.3 Central Dogma of Biology

• DNA? RNA? Protein
• All living organisms have DNA to store genetic
  information
• RNA is a messenger that carries genetic
  information
• Protein is the true message

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DNA- Stored Information

• Blueprints
• A, C, T, G (nucleotides)
• Double-stranded (ds)

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RNA- Carriers

• mRNA (messenger)
• rRNA (ribosomal)
• tRNA (transfer)
• A, C, U, G
• Single-stranded (ss)

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Protein- Functional Information

• Peptide bonds (covalent)
• Amino acids
• Beads on a string
• Proper folding and assembly (formfunction)
• Denaturation

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Transcription

• The synthesis of RNA under the direction of DNA

DNA 5- T G C C A T G A A C T C A T G C T A A
A T G-3 3-A C G G T A C T T G A G T
A C G A T T T A C-5
RNA 5- U G C C A U G A A C U C A U G C U A A
A U G -3
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Translation

• The production of proteins by decoding mRNA
  produced in transcription

RNA 5- U G C C A U G A A C U C A U G C U A A
A U G-3
Met (Start)
Asn
Ser
Cys
(Stop)
Protein M-N-S-C Met-Asn-Ser-Cys Methionine-
Asparagine-Serine-Cysteine
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DNA?RNA? Protein Interactive
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1.4 Cell Review

• Cell fundamental living unit of any living
  organism, exhibits all basic characteristics of
  life
• Obtain nutrients from environment to produce
  energy
• Metabolism all the chemical reactions that occur
  within a cell

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Cell Review

• DNA
• Species
• Organelles
• Prokaryotes and Eukaryotes
• Alternative spelling procaryotes and eucaryotes
• Cytology

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Cell Structure Review

• Prokaryotes
• DNA
• Single, Circular Chromosome
• Plasmids
• Ribosomes
• Cytoplasm
• Cell wall
• Plasma membrane
• Flagella, pili, endospores
• Binary fission

• Eukaryotes
• DNA
• Multiple, Linear Chromosomes
• Ribosomes
• Cytoplasm
• Specialized organelles
• Plasma membrane
• Mitosis
• 10x larger than prokaryotes

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Metabolism- All the chemical reactions that occur
within a cell

• Aerobic
• Requires oxygen
• Usually produces large amounts of ATP
• Krebs Cycle (Citric Acid Cycle)
• Electron Transport Chain (ETC)

• Anaerobic
• Occurs in the absence of oxygen
• Low production of ATP
• Glycolysis
• Fermentation
• Alcohol production
• CO2 production
• Lactic Acid

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Cell Review Generation Time

• Prokaryotes
• Time it takes for binary fission to occur
• 10 minutes to 48 hours
• E.coli 17 minutes
• S. aureus 30 minutes
• T. pallidum 33 hours

• Eukaryotes
• Time it takes for either mitosis or sexual
  reproduction to occur
• Yeast 80 minutes
• Aphid fly 5 days
• Rodents 4 months
• Humans 18 years

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1.5 Microbial Members Organization

• Taxonomy the science of classification of living
  organisms
• Classification arrangement of organisms into
  taxonomic groups (taxa) based on similarities or
  relationships
• Nomenclature assignment of names to various taxa
• Identification process of determining whether an
  isolate belongs to an established taxa or
  represents a previously unidentified species
• Bergeys Manual of Systematic Bacteriology

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Five-Kingdom System of Classification

• Robert Whittaker (1969)
• Monera bacteria archaeans (prokaryotes)
• Protista algae protozoa
• Fungi fungi
• Plantae plants
• Animalia animals
• NOTE viruses are not included in classification
  because they are not living organisms

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Three Domain System of Classification

• Carl Woese, University of Illinois (1977, 1990)
• Most favored classification by microbiologists,
  determined relatedness using RNA subunits (16S
  and 18S) from ribosomes

Microbes
Archaea
Bacteria
Eukarya
Includes Protista Fungi Plantae Animalia
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Binomial Nomenclature

• Binomial Nomenclature
• Genus (should always be capitalized)
• Genus specific epithet species
• Handwritten names should be underlined
• Typed names should be italicized
• Handwritten Escherichia coli
• Typed Escherichia coli

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Binomial Nomenclature (ctd)

• Abbreviations
• sp. Designates a single species
• First time written Escherichia coli
• Later written Escherichia sp.
• spp. Designates more than one species
• Clostridium spp. which can include 2 or more
• C. botulinum
• C. tetani