Introduction to Microbiology
Norazli [email protected]
norazlicucst.weebly.com (online note)DNEH 1292: Environmental Microbiology 1
Lecture 1
Environmental Microbiology
Assesment:Formative: 40%Midterm 20Assinment 10Lab report 10Summative 60Final Exam Theory 40
OSPE/LAB 20
Learning Outcomes…IAt the end of this section, students will have an appreciation of &/or be able to: The important developments in Microbiology Describe basic and specialised microscopy
techniques and their applications The extent of the microbial world Describe the important differences between
prokaryotes (Bacteria and Archaea) and eukaryotes
Learning Outcomes…IIAt the end of this section, students should be able to: Describe basic and specialized techniques for
quantifying microbial growth Summarize the process of bacterial and viral
reproduction and describe the dynamics of a bacterial growth curve and the plaque assay
Indicate how bacteria are divided into groups according to their phylogeny &/or metabolism
Lecture PlanScope of Microbiology Extent of the microbial worldHistory of MicrobiologyTechniques Microscopy and Staining Pure culture methods Quantitative methods Microbial growth curvePlaque assayMicrobial diversity Phylogeny Substrate utilization
ReferencesJensen, M.M. and Wright, DN. (1993) Introduction to Microbiology for the Health Sciences, 3rd. ed.Edward, A.L. (1997) 5th. Fundamentals of microbiology, Benjamin Cummings.Nestar, E.W. (1995), Microbiology : A Human Perspective, new York: Mc Graw Hill.Wesley A.V. (1992), Basic Microbiology, 7th. Ed. New York : Harper Collins.Brock T.D et al (1994), Biology of Microorganisms, 7th. Ed. Pretice Hall.Wikipedia
Introduction“microbiology’ - the study of microorganisms organisms to small to be seen with the naked eye except in large groups effects of large numbers often visible e.g., chemical reactions in soil horizons e.g., toxin and gas production in incompletely
sterilised food cans e.g., disease in animals and plants
Environmental Microbiology
Study of the composition and physiology of microbial communities in the environment.Such as Soil Water Air Sediments
Microbial World
VirusesBacteria (Eubacteria) and ArchaeabacteriaFungi (Yeasts and Molds)ProtozoaMicroscopic Algae
BenefitsMaintain balance of environment (microbial ecology)Basis of food chainNitrogen fixationPhotosynthesisDigestion, synthesis of vitaminsManufacture of food and drink
BenefitsGenetic engineeringSynthesis of chemical productsRecycling sewageBioremediation: use microbes to remove toxins (oil spills)Use of microbes to control crop pestsNormal microbiota
Harmful Effects
Cause disease (basis for bioterrorism)
Food spoilage
Pioneers of MicrobiologyRobert Hooke, UK (1665) Proposed the Cell Theory Observed cork with crude microscope All living things are composed of cells
Spontaneous generation Some forms of life could arise
spontaneously from non-living matter
Francesco Redi, IT (1668) Redi’s experiments first to dispprove S.G.
Pioneers of Microbiology
Antoni van Leeuwenhoek, DE (1673) First observed live microorganisms
(animalcules)Schleiden and Schwann, DE Formulated Cell Theory: cells are the
fundamental units of life and carry out all the basic functions of living things
Pasteur, FR and Tyndall, UK (1861) Finally disproved S.G.
Pioneers of Microbiology
Louis Pasteur (1822-1895), Chemist Fermentation (1857) Pasteurization: heat liquid enough to kill
spoilage bacteria (1864) Vaccine development – rabies Proposed the germ theory of disease Proposed aseptic techniques (prevent
contamination by unwanted microbes) Director of Pasteur Institute, Paris (1894)
Pioneers of Microbiology
Joseph Lister, UK (1867) Used phenol (carbolic acid) to disinfect
wounds First aseptic technique in surgeryRobert Koch, DE (1876) Postulates – Germ theory (1876) Identified microbes that caused anthrax
(1876), tuberculosis (1882) and cholera(1883)
Developed microbiological media & streak plates for pure culture (1881)
Branches of MicrobiologyBacteriology: study of bacteriaMycology: study of fungiImmunology: study of immunity Edward Jenner, UK: developed vaccination
(1798) Metchnikoff, RU: discovered phagocytes (1884) Paul Ehrlich, DE: theory of immunity (1890)Virology: study of viruses Beijerinck, NE: discovered intracellular
reproduction of TMV; coined the term “virus” (1899)
Branches of Microbiology
Parasitology: study of protozoa and parasitic wormsChemotherapy Treatment of disease by using chemical means Antibiotics produced naturally Synthetic drugs Paul Ehrlich (1878) – used arsenic compounds to
fight disease – ‘magic bullet’
Branches of Microbiology
Chemotherapy Alexander Fleming, Scotland (1928) discovered
penicillin Selman Waksman, Ukraine (1944) discovered
streptomycin
Problems Toxicity of drugs => Selective toxicity Resistance of bacteria to drugs
Branches of Microbiology
Recombinant DNA Technology Recombinant DNA Genetic engineering/biotechnology Microbial genetics – mechanism by which
microbes inherit genes Molecular biology – structure and
function (expression) of genes Molecular epidemiology/diagnostics
Branches of Microbiology
Biotechnology GMOs/GEMs for industrial, pharmaceutical and
agricultural applications Improvements of agriculture (plants and
animals) Gene therapy: inserting a missing gene or
replacing a defective one in human cells
Classification of Microorganisms
A. Principles of Classification and Nomenclature
B. Eukaryotic OrganismsC. Prokaryotic Organisms
Principles of Classification and Nomenclature
Taxonomy Kingdom
Phylum (pl: Phyla)
Class
Order
Family
Genus (pl: Genera)
Species (pl: Species)
Principles of Classification and Nomenclature
Nomenclature Scientific name (Systematic Name)
Binomial System of Nomenclature
Genus name + species name italicized or underlined genus name is capitalized and may be abbreviated species name is never abbreviated.
eg: Bacillus subtilisB. subtilis
Eukaryotic Organisms
Eukaryotic Kingdoms Kingdom Protista
(Protozoa and Algae)
Kingdom Fungi
Kingdom Plantae
Kingdom Animalia
Prokaryotic Organisms
Prokaryotic Kingdoms Kingdom Eubacteria Kingdom Archaeobacteria
SYMBIOSIS is the interaction between 2 different organisms living together
HOST- usually the LARGER of the 2 organisms
SYMBIONT- usually the SMALLER member
THE THREE SYMBIOTIC RELATIONSHIPS ARE...
PARASITISM MUTUALISM COMMENSALISM
PARASITISM
Is a relationship where the Symbiont lives in/on the HostThe Symbiont (or Parasite) BENEFITS The Host is HARMEDFor example, the tick in the picture above is a parasite. It benefits by extracting blood from its human host. The human is harmed because
Is a relationship between the host and a symbiont, where both organisms benefit and neither is harmed.The relationship can be long or short term.For example, in the photo above, the host flower benefits by being pollinated by the traveling butterfly. The symbiont butterfly benefits from the nectar that it extracts from the flower.
Mutualism
COMMENSALISM
Is a relationship between the host and symbiont, where the symbiont benefits and the host is neither helped nor harmed.The symbiont benefits by receiving transportation, housing, and/or nutrition.For example, in the photo above the symbiont barnacles receive transportation from the host whale. The host whale is neither helped nor harmed by the barnacles.