Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings MICROBIOLOGY CHAPTER 9 part a An Introduction to Taxonomy: the Bacteria Microbiology 130 Roberta Brashear-Kaulfers
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Taxonomy Taxonomy: the Science of Classification The science of classifying organisms Provides universal names for organisms Provides a reference for identifying organisms Groupings of organisms WHY Classify? Establish criteria for ID Arrange related organisms into groups Provide information about evolution of organisms
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Taxonomy Systematics or phylogeny: The study of the evolutionary history of organisms. All Species Inventory is underway ( ) To identify all species of life on Earth Linnaeus – ( )Father of modern taxonomy Created Binomial nomenclature 2 names- Genus-species
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Levels of Classification Kingdom Division/Phyta/Phylum SubPhylum Class Order Family Genus Species/Specific Epithet Subspecies/Strain
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Dichotomous Key- to Identify Bacteria
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Taxonomy 1735Plant and Animal Kingdoms 1857Bacteria and fungi put in the Plant Kingdom 1866Kingdom Protista proposed for bacteria, protozoa, algae, and fungi 1937Prokaryote introduced for cells "without a nucleus" 1961Prokaryote defined as cells in which nucleoplasm is not surrounded by a nuclear membrane 1959Kingdom Fungi 1968Kingdom Prokaryotae proposed 1978Two types of prokaryotic cells found
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings 5 Kingdom System or 6 Kingdom System Kingdom Monera - Eubacteria - new bacteria - Prokarya - Archaebacteria – old bacteria Kingdom Protista- 1 celled organisms- Eukarya Kingdom Fungi- multicellular fungi/yeast- Eukarya Kingdom Plantae- photosynthetic plants- Eukarya Kingdom Animalia- animals from zygote- Eukarya
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings The Three-Domain System Table 10.1
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings The Three-Domain System Figure 10.1
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Table 10.2
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Endosymbiotic Theory Figures 10.2, 10.3
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Scientific Binomial Source of Genus Name Source of Specific Epithet Klebsiella pneumoniaeHonors Edwin KlebsThe disease Pfiesteria piscicidaHonors Lois PfiesterDisease in fish Salmonella typhimuriumHonors Daniel SalmonStupor (typh-) in mice (muri-) Streptococcus pyogenes Chains of cells (strepto-) Forms pus (pyo-) Penicillium chrysogenum Tuftlike (penicill-)Produces a yellow (chryso-) pigment Trypanosoma cruziCorkscrew-like (trypano-, borer; soma-, body) Honors Oswaldo Cruz Scientific Names
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Taxonomic Hierarchy Figure 10.5
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Species Definition Eukaryotic species: A group of closely related organisms that breed among themselves Prokaryotic species: A population of cells with similar characteristics Clone: Population of cells derived from a single cell Strain: Genetically different cells within a clone Viral species: Population of viruses with similar characteristics that occupies a particular ecological niche
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Domain Eukarya Animalia: Multicellular; no cell walls; chemoheterotrophic Plantae: Multicellular; cellulose cell walls; usually photoautotrophic Fungi: Chemoheterotrophic; unicellular or multicellular; cell walls of chitin; develop from spores or hyphal fragments Protista: A catchall for eukaryotic organisms that do not fit other kingdoms
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Prokaryotes Figure 10.6
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings The Tree of Life is replaced by a Shrub Universal ancestor- unlikely Broke into 2 lines –Bacteria and Archae Still not correct, both share similar genes Some organisms have genes from all 3 Domains “Shrub of Life” theory - lateral gene swapping Archae made of : - Methanogens- - Extreme halophiles- Extreme thermoacidophiles- have extremozymes at 80*
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Classification of Viruses Acellular infectious agents DNA and protein coat Classified by chemical and physical characteristics Shape, Symmetry of protein coat Presence of envelope, Enzymes and/or tail, Virology- study of viruses is important because: 1) recognized branch of Microbiology 2) Concern to health scientists. Many cause diseases in humans, animals, plants and other microbes
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Bergey’s Manual of Determinative Bacteriology Provides identification schemes for identifying bacteria and archaea Morphology, differential staining, biochemical tests Bergey’s Manual of Systematic Bacteriology Provides phylogenetic information on bacteria and archaea Based on rRNA sequencing Approved Lists of Bacterial Names Lists species of known prokaryotes Based on published articles References
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Identification Methods Morphological characteristics: Useful for identifying eukaryotes Differential staining: Gram staining, acid- fast staining Biochemical tests: Determines presence of bacterial enzymes Figure 10.8
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Phage Typing
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
Serology Combine known antiserum plus unknown bacterium Slide agglutination ELISA Western blot