Introduction to Microbiology

1. Introduction to Microbiology Module 1

2. 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

3. 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

4. Prokaryotic Bacteria Archaea Eukaryotic Algae Fungi Protozoa Acellular Virus Viroid Prion Subdivisions in Microbiology

5. 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

6. 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

7. 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.

8. 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

9. 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 Koch’s Postulates

10. Chemotherapy Antibiotics Synthetic drugs Immunology Study of disease and the body’s 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 Microbiology Today

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

12. Macromolecules Carbohydrates Lipids Protein Nucleic Acid Atoms Bonding Polar and nonpolar molecules Chemical reactions Solvents & Solutes Acids & Bases, pH Organic molecules 1.2 Molecules & Metabolism Review

13. 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

14. 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

15. 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 Covalent Bonds

16. 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

17. 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

18. 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)

19. 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

20. 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

21. 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

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

23. 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

24. Products of Metabolism • Water • Energy production • CO2 • Changes in pH • Acid and Base

25. 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

26. DNA- Stored Information • “Blueprints” • A, C, T, G (nucleotides) • Double-stranded (ds)

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

28. Protein- Functional Information • Peptide bonds (covalent) • Amino acids • “Beads on a string” • Proper folding and assembly (form=function) • Denaturation

29. 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’

30. 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 AA U G-3’ Asn Ser Cys * (Stop) Met (Start) Protein M-N-S-C Met-Asn-Ser-Cys Methionine- Asparagine-Serine-Cysteine

31. DNARNA Protein Interactive

32. 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

33. Cell Review • DNA • Species • Organelles • Prokaryotes and Eukaryotes • Alternative spelling procaryotes and eucaryotes • Cytology

34. 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 Cell Structure Review

35. Aerobic Requires oxygen Usually produces large amounts of ATP Kreb’s 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 Metabolism- All the chemical reactions that occur within a cell

36. 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 Cell Review: Generation Time

37. 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 • Bergey’s Manual of Systematic Bacteriology

38. 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

39. 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

40. 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

41. 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