Bacteria
Origins - Three Domain Classification
PROKARYOTESEU
I. Origins of Bacteria
EubacteriaArchaebacteria
Prokaryotes
A. Prokaryotes = 1. Kingdom Eubacteria
2. Kingdom Archaebacteria3. Prokaryote =
does not have a nucleus
I.I. OriginsOriginsB. B. 3.5 billion years ago3.5 billion years ago
C. FIRST LIFE FORMSC. FIRST LIFE FORMS were: were: Archaebacteria, or ancient bacteria Archaebacteria, or ancient bacteria
(how do we know this?)(how do we know this?)
early Earth atmosphere had almost no Oearly Earth atmosphere had almost no O22
D. EubacteriaD. Eubacteria is true bacteriais true bacteria ((EuEu = true= true))
EuEukaryote = karyote = true nucleustrue nucleus
II. Archaebacteria
A. General Info. 1. EXTREME ! Primitive bacteria2. Live in extreme or harsh environments
B. Three kinds of Archaebacteria:
1. Halophiles
= live in very basic or salty environments E.g. Great Salt lake, Dead Sea
2. Methanogens
–Anaerobic (don’t need O2 )
–Make methane gas (CH4 ) Swamp
3. Thermophiles
– live in hot or acidic environments (~pH 1-4)• Near undersea volcanic vents• Sulphur Springs• Hot springs in Yellowstone National Park
III. EubacteriaIII. Eubacteria
A. General A. General 1. Ubiquitous1. Ubiquitous = they exist everywhere, = they exist everywhere,
most of the most of the bactibacti. we know. we know
2. Harmful2. Harmful –– pathogenic (they cause pathogenic (they cause disease)disease)
3. Helpful3. Helpful –– they have a variety of usesthey have a variety of uses
4. Odd means of getting nutrients
• Chemo – autotrophic (“eat”chemicals)
• Some “eat” NH3 (ammonia)• Some “eat” H2S (hydrogen sulfide)
» Sulfide-eating bacteria
Helpful Bacteria1. Food & Drink Production
Fermentation (drinks)– Wine, beerDairy products– Cheese, sour cream, yogurt, sourdough,
Other-Pickles, vinegar,sauerkraut
Helpful Bacteria
2. Sewage DecompositionBacteria break down the organic matter
Helpful Bacteria
3. Water Treatment
Helpful Bacteria
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Where is most of the Nitrogen found on planet Earth?In the atmosphere
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Where do plants need it to be?In the soil
4. Nitrogen Fixation in roots– Helps plants take up H2 O and
nutrients from soil
Helpful Bacteria5. Bio-mineralization in Mining
– Bacteria concentrate desired elements from ore
– E.g. Au (gold)
Cu (copper)
Ralstonia metallidurans, is capable of precipitating dissolved gold.
Helpful Bacteria6. Bio-
remediation– Microbes can
help repair damaged ecosystems
– Pseudomonas , a common type of oil eating bacteria, is used around the world to help clean up oil spills.
Helpful Bacteria
7. Human Recreation
= Artificial Snow- Making– Bacteria allow
H2 O to form ice crystals
Bacterial Classification1. Shape and Groupings
2. Cell wall composition
3. Environment
4. DNA Sequences
Bacterial Cell
Bacterial StructureBacterial StructureCell WallCell Wall
Prevents cell from rupturingPrevents cell from rupturingComposition of cell wall helps to identify Composition of cell wall helps to identify bacteriabacteria
Bacterial StructureBacterial Structure
Cell MembraneCell MembraneF(xF(x) = support & protect) = support & protectDifferentially permeableDifferentially permeable
CytoplasmCytoplasmContains organelles (nonContains organelles (non--membranous)membranous)
Bacterial StructureBacterial StructureGenetic MaterialGenetic Material
Single, circular chromosomeSingle, circular chromosomePlasmid Plasmid = extra chromosome that can = extra chromosome that can replicate separately from the main replicate separately from the main chromosomechromosome•• Use as vectorUse as vector for biological engineeringfor biological engineering•• Can pass genes for Can pass genes for antibiotic resistanceantibiotic resistance to to
other bacteria (sometimes resistance to other bacteria (sometimes resistance to
several antibiotics @ one time)several antibiotics @ one time)
Bacterial StructureBacterial StructureRibosomesRibosomes
F(xF(x) is to synthesize proteins) is to synthesize proteins
Bacterial StructureBacterial Structure
Capsule (Slime Layer)Capsule (Slime Layer)viscousviscous coating outside of bacteria cell wallcoating outside of bacteria cell wallF(x)sF(x)s::
•• ProtectionProtection•• bacteriabacteria’’s s pathogenicitypathogenicity (or ability to cause disease)(or ability to cause disease)•• Protects bacteria from the Immune System (WBCProtects bacteria from the Immune System (WBC’’s)s)
Bacterial StructureBacterial StructureOther structures (Appendages)Other structures (Appendages)
FlagellaFlagella (protein appendage)(protein appendage)•• F(xF(x) = locomotion) = locomotion•• Cell can have one, two, or manyCell can have one, two, or many
PiliPili (hair(hair--like extensions)like extensions)•• F(x)sF(x)s = attachment to host and transfer of = attachment to host and transfer of
genetic materialgenetic material
FimbriaeFimbriae (shorter than (shorter than pilipili))•• F(xF(x) = adhesion to surfaces) = adhesion to surfaces
Flagella
Bacterial ShapesBacterial ShapesA. TypicalA. Typical
1.1. Coccus/CocciCoccus/Cocci = = spherical or roundspherical or round
2.2. Bacillus/BacilliBacillus/Bacilli = = rodrod--shapedshaped
3.3. Spirillum/SpirilliSpirillum/Spirilli = spiral= spiral--shapedshaped
Bacterial Shapes
Bacterial GroupingsBacterial Groupings
Groups determined by the plane Groups determined by the plane in which the cell dividesin which the cell divides
Bacterial Groupings
– 1 plane =• diplo- (pair)• strepto- (chain)
– 2 planes =• tetrad (packet of 4)
– Several planes @ random = • staphylo-
(grape-like clusters)
Identify shapes & groupings
Bacterial ShapesB. Atypical1. PleomorphicVariable in shape and sizeEg. Stella (stars)Eg. Arcula (cubes)
2. MycoplasmasLack rigid cell wallsCan change shape
GRAM STAINING• History & Definitions
– Developed by Hans Christian Gram in 1884
– Helps to identify different types of bacteria (a differential stain)
– Stain uses differences in cell wall composition to differentiate between bacteria
– Can help determine which type of antibiotics will be most effective against a particular bacteria
Gram Positive Cells• Stain purple
– Has thick peptidoglycan layer
• More susceptible to Penicillin
Thick layer of peptidoglycan
Gram Positive
POSITIVELY PURPLE!!!
Gram Negative
Thin layer of peptidoglycan
Gram Negative
• Stain pink/light red
– A thin layer of peptidoglycan (space)
• Less susceptible to Penicillin than gram positive
Penicillin (a fungus)Penicillin (a fungus)•• Antibiotic inhibits synthesis of Antibiotic inhibits synthesis of
peptidoglycanpeptidoglycan; ; used on actively growing used on actively growing
organisms.organisms.––Gram (+) cellsGram (+) cells PenicillinPenicillin
works works ––Gram (Gram (--) cells) cells PencillinPencillin
doesndoesn’’t work so wellt work so well
Overview of Staining
Why do we stain?
•To better view a cell’s structure.
Gram Staining Procedure
Steps (abbreviated):1) Add primary (1o) stain – Crystal Violet
2) Add mordant to cells – Iodine
3) Add decolorizer to cells – Alcohol
4) Add secondary (2o) stain - Safranin
Gram Staining Steps
Bibliography• Thanks to Jordan Sonneberg for the start of this ppt! • Yellowstone sciences.unlv.edu/.../Pages/episode2.htm Retrieved 11/12/08• Yellowstone serc.carleton.edu/microbelife/research_methods/ 11/212/08• Swamp Protegeu http://photos.mongabay.com/pt/Swamp_Shaded.htm Retrieved 11/12/08• Image of ribosomes sciences.unlv.edu/.../Pages/episode2.htm Retrieved 11/27/07• Image of Bacterial cell wall pbdb.itan.kyoto-u.ac.jp/saikin-e.html Retrieved 11/27/07• Map of Great Salt Lake ut.water.usgs.gov/greatsaltlake/index.html Retrieved 11/27/07
• Image of Dead Sea www.pjsoaps.com/1DeadSeaSpa.html Retrieved 11/27/07• Pickles http://www.getrichslowly.org/images/pickles1.jpg Retrieved 11/12/08• Yogurt http://wikigreenfrost.pbwiki.com/Helpful+or+Harmful Retrieved 11/12/08• Sewage treatment plant
http://www.biosolids.com.au/uploads/images/Sewage%20treatment%20process%20v2a.jpg Retrieved 11/12/08 • Water Treatment http://www.saskatoon.ca/org/water_treatment/wastewater_treatment/WWTP1a.jpg Retrieved
11/12/08 • Sauerkraut http://www.recipeathome.info/pictures/1171431564SAUERKRAUT.jpg Retrieved 11/12/08 • Nitrogen-fixing bacteria http://telstar.ote.cmu.edu/environ/m3/s4/graphics/embedded/nitronodules.gif
Retrieved 11/12/08• Biomineralization of gold http://www.biotech-weblog.com/50226711/biomineralization_of_gold_by_bacteria.php
Retrieved 11/12/08• Bioremediation http://jackandshaun.pbwiki.com/ Retrieved 11/13/08 • Oil-eating Bacteria http://www.jamstec.go.jp/jamstec/bio2.gif Retrieved 11/13/08• Bacterial shapes http://porpax.bio.miami.edu/~cmallery/150/proceuc/c8.27x3.bact.shapes.jpg retrieved 11/13/08