3. Taxonomy
a Organizing, classifying and
naming living things
a Formal system originated by
Carl von Linné (1701-1778)
a Identifying and classifying
organisms according to
specific criteria
a Each organism placed into a
classification system
6. BACTERIA
a ARCHAEBACTERIA
• Introns in DNA a EUBACTERIA
• Lack peptidogycan in • Includes most
cell walls bacteria
• Live in extreme • Most have one of three
environments shapes
• May be divided into up
to 12 phyla
• Classification is
controversial
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7. TYPES OF ARCHAEBACTERIA
Methanogens
living in
Thermoacidophilies sewage
Living in hot springs
Extreme halophile
living in the Great Salt Lake Padaga
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10. Most Species of Eubacteria may be
Grouped Based on Staining
a Gram-Negative a Gram-Positive
• Lack thicker layer of • Thicker layer of
peptidoglycan peptidogycan
• Stain purple
• Stain pink
• Exotoxins (released
• Endotoxins when bacteria die)
Gram- negative Gram-positive
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13. Bacterial Taxonomy Based on
Bergey’s Manual
a B ergey’s M anual of D eterminative B acteriology
– five volume resource covering all known
procaryotes
• classification based on genetic information –
p h y lo g e n e t ic
• two domains: Archaea and Bacteria
• five major subgroups with 25 different phyla
14. Major Taxonomic Groups of Bacteria
a V o l 1A : D o m a i n A r c h a e a
• primitive, adapted to extreme habitats and
modes of nutrition
a V o l 1B : D o m a i n B a c t e r i a
a Vol 2-5:
• P h y l u m P r o t e o b a c t e r i a – Gram-
negative cell walls
• P h y l u m F i r m i c u t e s – mainly Gram-
positive with low G + C content
• P h y l u m A c t i n o b a c t e r i a – Gram-
positive with high G + C content
15. Naming and Classifying
microorganisms
• Linnaeus system for scientific nomenclature
• Each organism has two names:
1) Genus
2) Specific epithet
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16. Scientific Names
a Italicized or underlined.
The genus is capitalized, and the specific epithet is with lowercase
a Could be as an honor for the scientist
a A Latin origin
e.g. Escherichia coli (E. coli)
- discoverer: Theodor Escherich In
- describes the habitat (colon/intestine) intestine
e.g. Staphylococcus aureus (S. aureus)
- Clustered (staphylo), spherical (cocci) On skin
- 27/02/2012
Gold colored colonies (aureus) Padaga
Masdiana 16
17. Binomial Nomenclature
Examples: Escherichia coli, E. coli, Escherichia spp., and
“the genus Escherichia”
The genus name (Escherichia) is always capitalized
The species name (coli) is never capitalized
The species name is never used without the genus name
(e.g., coli standing alone, by itself, is a mistake!)
The genus name may be used without the species
name (e.g., Escherichia may stand alone, though when
doing so it no longer actually describes a species)
When both genus and species names are present, the
genus name always comes first (e.g., Escherichia coli,
not coli Escherichia)
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18. Binomial Nomenclature
Both the genus and species names are always italicized
(or underlined)—always underline if writing binomials by
hand
The first time a binomial is used in a work, it must be
spelled out in its entirety (e.g., E. coli standing alone in a
manuscript is not acceptable unless you have already
written Escherichia coli in the manuscript)
The next time a biniomial is used it may be abbreviated
(e.g., E. for Escherichia) though this is done typically only
when used in combination with the species name (e.g.,
E. coli)
The species name is never abbreviated
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19. Binomial Nomenclature
It is a good idea to abbreviate unambiguously if there is
any potential for confusion (e.g., Enterococcus vs.
Escherichia)
These rules are to be followed when employing binomial
nomenclature even in your speech. It is proper to refer
to Escherichia coli as E. coli or even as Escherichia, but
it is not proper to call it coli or E.C.!
When in doubt, write the whole thing out (and underline)!
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20. Types of Eukaryotes
Protozoa Algae
a Unicellular eukaryote a Unicellular/multicellular
a Absorb or ingest organic eukaryote
chemicals a Has cellulose cell walls
a May move using a Gain energy through
pseudopods, cilia or photosynthesis
flagella a Produce molecular and
a e.g. Amoeba organic compounds
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21. Fungi (singular: Fungus)
a Eukaryotes
a Chitin cell walls
a Use organic chemicals for
energy
a Molds and mushrooms are
multicellular, consists of
mycelia (composed of
filaments called hyphae)
a Yeasts are unicellular
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22. Multicellular animal
parasites
a Helminths: flatworms and
roundworms
a Multicellular
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23. Viruses
a Too small to be observed with light microscope
a Consists of DNA/RNA core
a Core is surrounded by protein coat
a Coat may be enclosed in a lipid envelope
a Viruses are replicated only when they are in living
host cell
a Bacteriophage-viruses that infect bacteria
a Viroids-nucleic acid without protein coating
a Prions- Infectious protenacious particles
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