2. 1 BACTERIA Chapter 19.1

3. 2 This is a pore in human skin and the yellow spheres are bacteria

4. 3 Clean skin has about 20 million bacteria per square inch

5. 4 Evolution/Classification  Prokaryotes  The oldest fossils known, nearly 3.5 billion years old, are fossils of bacteria- like organisms.  Evolution has yielded many species adapted to survive where no other organisms can.  Grouped based on: Structure, physiology, molecular Composition, reaction to specific types of stain (Gram Positive/Gram Negative). Eubacteria= Germs/bacteria Archaebacteria

6. 5 Kingdom Archaebacteria  First discovered in extreme environments  Methanogens: Harvest energy by converting H 2 and CO 2 into methane gas Anaerobic, live in intestinal tracts  Extreme halophiles: Salt loving, live in Great Salt Lake, and Dead sea.  Thermoacidophiles: Live in acid environments and high temps. Hot Springs, volcanic vents

7.  Depending on the species, bacteria can be aerobic which means they require oxygen to live or anaerobic which means oxygen is deadly to them. Green patches are green sulfur bacteria. The rust patches are colonies of purple non sulfur bacteria. The red patches are purple sulfur bacteria.

8. 7 Chemosynthetic bacteria use the sulfur in the “smoke” for energy to make ATP.

9. 8 The red color of this snow is due to a blue-green bacteria

10. 9 Kingdom Eubacteria  Can have one of three basic shapes 1.Bacilli – rod-shaped 2.Spirilla – spiral-shaped 3.Cocci – sphere-shaped Strepto – in chains Staphylo – grape-like clusters

11. 10 BACTERIA PICS

12. 11 Bacillus bacteria are rod shaped

13. 12 Coccus bacteria are ball shaped

14. 13 Spirillium bacteria have a corkscrew shape

15. 14 Diplo-bacteria occur in pairs, such as the diplococcus bacteria that causes gonorrhea

16. 15 Staphylo - occur in clumps, such as this staphylococcus that causes infections of cuts

17. 16 Strepto- occur in chains of bacteria, such as this streptococcus bacteria that causes some types of sore throats

18. Cyanobacteria You may have seen them as "green slime" in your aquarium or in a pond. Cyanobacteria can do "modern photosynthesis", which is the kind that makes oxygen from water. All plants do this kind of photosynthesis and inherited the ability from the cyanobacteria.

19.  The Gram stain, which divides most clinically significant bacteria into two main groups, is the first step in bacterial identification.  Bacteria stained purple are Gram + - their cell walls have thick petidoglycan.  Bacteria stained pink are Gram – their cell walls have have thin peptidoglycan and lipopolysaccharides.

20. 19 STRUCTURE OF BACTERIA StructureFunction Cell WallProtects and gives shape Outer Membrane Protects against antibodies (Gram Neg. Only) Cell Membrane Regulates movement of materials, contains enzymes important to cellular respiration CytoplasmContains DNA, ribosomes, essential compounds Chromo- some Carries genetic information PlasmidContains some genes obtained through recomb. Capsule & Slime Layer Protects the cell and assist in attaching cell to other surfaces EndosporeProtects cell agains harsh enviornments PilusAssists the cell in attaching to other surfaces FlagellumMoves the cell

21. 20 No Nucleus-DNA in Cytoplasm

22. 21 Eubacteria - Nutrition and Growth  Heterotrophic or Autotrophic  Some are Photoautotrophs – Use sunlight for Energy  Some are Chemoautotrophs.  Many are Obligate Anaerobes. (live w/o O 2 )  Ex. Clostridium tetani – Tetanus  Some are Faculatative Anaerobes (can live w/ or w/o O 2 )  Ex. Escherichia Coli  Some are Obligate Aerobes (need O 2 to survive) Ex.) Mycobacterium tuberculosis  Temperature requirements Some are Thermophilic, Some prefer acidic envmt.

23. 22 REPRODUCTION IN BACTERIA

24. 23 BACTERIA REPRODUCES BY FISSION First the chromosomal DNA makes a copy The DNA replicates

25. 24 NEXT THE CYTOPLASM AND CELL DIVIDES The two resulting cells are exactly the same

26. 25 In addition to the large chromosomal DNA, bacteria have many small loops of DNA called Plasmids

27.  Bacteria can reproduce sexually - conjugation or asexually - binary fission.

28. 27 CONJUGATION

29. 28 Bacteria and Disease DiseasePathogenAreas affected Mode of transmission BotulismClostridium botulinumNervesImproperly preserved food CholeraVibrio choleraeIntestineContaminated water Dental CariesStreptococcus mutans, sanguis, salivarius TeethEnvironment to mouth GonorrheaNeisseria gonorrhoeaeUrethra, fallopian Sexual contact Lyme diseaseBerrelia burgdorferiSkin, jointsTick bite Rocky Mountain SF Rickettsia recketsiiBlood, skinTick bite Salmonella IntestineContaminated food, water Strep throatStreptococcus pyogenesURT, blood, skin Sneezes, coughs, etc. TetanusCostridium tetaniNervesContaminated wounds TuberculosisMycobacterium tuberculosisLung, bones coughs

30. 29 Helicobacter pylori is the pathogenic bacteria that can causes ulcers

31. 30 Leprosy is a bacterial infection that decreases blood flow to the extremities resulting in the deterioration of toes, ears, the nose and the fingers.

32. 31 BOTULISM

33. 32 ROCKY MOUNTAIN SF

34. 33 LYME DISEASE

35. 34 SALMONELLA

36. 35 STREP THROAT

37. 36 TUBERCULOSIS

38. 37 Common Antibiotics AntibioticMechanismTarget bacteria PenicillinInhibits cell wall synthesisGram Positive AmpicillinInhibits cell wall synthesisBroad spectrum BacitracinInhibits cell wall synthesisGram Positive – Skin Ointment CephalosporinInhibits cell wall synthesisGram Positive TetracyclineInhibits Protein SynthesisBroad spectrum StreptomycinInhibits Protein SynthesisGram Neg. tuberculosis Sulfa drugInhibits cell metabolismBacterial meningitis, UTI RifampinInhibits RNA synthesisGram Pos., some Neg. QuinolinesInhibits DNA SynthesisUTI

39. 38 Some Final Information  Because antibiotics have been overused, many diseases that were once easy to treat are becoming more difficult to treat.  Some Bacteria are Useful Ex. Producing and Processing food Breaking down dead organic material Make unripened cheese like ricotta and cottage by breaking down the protein in milk.