1. Bacteria and Humans

2. Describe the ways that bacteria can cause disease in humans Specify how antibiotic resistance has come about, and describe ways that bacteria resist antibiotics List three ways that bacteria are helpful to humans

3. Bacteria cause disease Bacteria benefit us in food preparation and in environmental, chemical, and mining process

4. Bacteria and Disease Pathology: study of disease Pathogens: bacteria that cause disease Toxins (From Greek for poison used in arrows): Poison made from living cells –Hemotoxins: destroy RBCs, Pit Viper Venom –Necrotoxins: destroy all tissue types, Brown Recluse, and Necrotizing Fasciitis –Neurotoxins: nerve cells, black widow, scorpions, box jelly fish

5. Exotoxins: toxins made of protein Botulinum from Clostridium botulinum. –One of most poisonous substances –The most poisonous protein –Used in small doses to treat muscle spasms, and as botox –Poor canning

6. Clostridium perfringens In every bit of dirt you can find Can cause gangrene & food poisoning

7. Clostridium tetani –Causes tetanus –Uncontrolled muscle spasms In the jaw = lockjaw

8. DiseasePathogenArea AffectedMode of Transmission BotulismClostridium botulinumNervesImproperly preserved foods CholeraVibrio choleraeIntestineContaminated water Dental caries (tooth decay) Streptocooccus mutans and salivarius TeethEnvironment GonorrheaNeisseria gonorrhoeaeUrehtra, fallopian tubes, epididymis Sexual contact Lyme diseaseBorrelia burgdorferiSkin, joints, heartTick bite Rocky mountain spotted fever Rickettsia ricketsiiBlood, skinTick bite Salmonella food poisoning SalmonellaIntestineContaminated water and food Strep throatStreptococcus pyogenes Upper respiratory tract, blood, skin Airborne TetanusClostridium tetaniNerves at synapseswounds TuberculosisMycobacterium tuberculosis Lung, bones, other organs coughs

9. Endotoxins: toxins made of lipids and carbohydrates –Inside bacteria –Hurt us when they die

10. Antibiotics Drugs that interfere with cellular functions Penicillin: can’t make cell walls –Some are allergic Tetracycline: bacteria can’t make proteins Sulfadrugs: made in labs Broad-spectrum drugs: affect a variety of organisms

11. Antibiotic Resistance When a few mutant bacteria survive antibiotics a resistant population will grow as their descendents. Antibiotics puts selective pressure for resistant bacteria to succeed. Overuse of antibiotics is making generations of resistant bacteria difficult to treat

12. Useful bacteria Bacteria break down waste in treatment facilities Bacteria ferment lactose to make products such as buttermilk, sour cream, and yogurt. Bacteria digest protein in milk to make cheese –Digest carbs in cabbage to make sauerkraut

13. Useful bacteria Produce chemicals and fuels Clean up environmental disasters