Bacteria
Origins - Three Domain Classification EU PROKARYOTES
I. Origins of Bacteria Prokaryotes Eubacteria Archaebacteria A. Prokaryotes = 1. Kingdom Eubacteria 2. Kingdom Archaebacteria 3. Prokaryote = does not have a nucleus
I. Origins B. 3.5 billion years ago C. FIRST LIFE FORMS were: Archaebacteria, or ancient bacteria (how do we know this?) early Earth atmosphere had almost no O 2 D. Eubacteria is true bacteria (Eu = true) Eukaryote = true nucleus
II. Archaebacteria A. General Info. 1. EXTREME! Primitive bacteria 2. 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 O 2 ) Make methane gas (CH 4 ) 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. Eubacteria A. General 1. Ubiquitous = they exist everywhere, most of the bacti.. we know 2. Harmful pathogenic (they cause disease) 3. Helpful they have a variety of uses
4. Odd means of getting nutrients Chemo autotrophic ( eat chemicals) Some eat NH 3 (ammonia) Some eat H 2 S (hydrogen sulfide)» Sulfide-eating bacteria
Helpful Bacteria 1. Food & Drink Production Fermentation (drinks) Wine, beer Dairy products Cheese, sour cream, yogurt, sourdough, Other -Pickles, vinegar, sauerkraut
Helpful Bacteria 2. Sewage Decomposition Bacteria break down the organic matter
3. Water Treatment Helpful Bacteria
Helpful Bacteria Where is most of the Nitrogen found on planet Earth? In the atmosphere Where do plants need it to be? In the soil 4. Nitrogen Fixation in roots Helps plants take up H 2 O and nutrients from soil
Helpful Bacteria 5. Bio-mineralization in Mining Bacteria concentrate desired elements from ore E.g. Au (gold) Ralstonia metallidurans, is capable of precipitating dissolved gold. Cu (copper)
Helpful Bacteria 6. Bioremediation 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 H 2 O to form ice crystals
Bacterial Classification 1. Shape and Groupings 2. Cell wall composition 3. Environment 4. DNA Sequences
Bacterial Cell
Cell Wall Bacterial Structure Prevents cell from rupturing Composition of cell wall helps to identify bacteria
Bacterial Structure Cell Membrane F(x) ) = support & protect Differentially permeable Cytoplasm Contains organelles (non-membranous)
Bacterial Structure Genetic Material Single, circular chromosome Plasmid = extra chromosome that can replicate separately from the main chromosome Use as vector for biological engineering Can pass genes for antibiotic resistance to other bacteria (sometimes resistance to several antibiotics @ one time)
Bacterial Structure Ribosomes F(x) ) is to synthesize proteins
Bacterial Structure Capsule (Slime Layer) viscous coating outside of bacteria cell wall F(x)s: Protection bacteria s pathogenicity (or ability to cause disease) Protects bacteria from the Immune System (WBC s)
Bacterial Structure Other structures (Appendages) Flagella (protein appendage) F(x) ) = locomotion Cell can have one, two, or many Pili (hair-like extensions) F(x)s = attachment to host and transfer of genetic material Fimbriae (shorter than pili) F(x) ) = adhesion to surfaces
Flagella
Bacterial Shapes A. Typical 1. Coccus/Cocci = spherical or round 2. Bacillus/Bacilli = rod-shaped 3. Spirillum/Spirilli = spiral-shaped shaped
Bacterial Shapes
Bacterial Groupings Groups determined by the plane in 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 Shapes B. Atypical 1. Pleomorphic Variable in shape and size Eg. Stella (stars) Eg. Arcula (cubes) 2. Mycoplasmas Lack rigid cell walls Can 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) Antibiotic inhibits synthesis of peptidoglycan; used on actively growing organisms. Gram (+) cells Penicillin works Gram (-)( ) cells Pencillin doesn t t 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 (1 o ) stain Crystal Violet 2) Add mordant to cells Iodine 3) Add decolorizer to cells Alcohol 4) Add secondary (2 o ) 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