1. Chapter 26 Microbial Growth Control

2. Physical Antimicrobial Control Clicker Question:

3. Physical Antimicrobial Control Clicker Question:

4. Thermal Death Curve: Mesophilic Bacterium Clicker Question:

5. Thermal Death Curve: Mesophilic Bacterium Clicker Question:

6. Thermal Death Curve: Mesophilic Bacterium Clicker Question:

7. Thermal Death Curve: Mesophilic Bacterium Clicker Question:

8. Decimal Reduction Time vs Temperature Clicker Question:

9. Pasteurization Times and Temperatures: Pasteur’s original: half hour at 63 o C-66 o C as a Batch. Originally designed to prevent spoilage of wine. Later applied to milk to prevent Mycobacterium bovis transmission of TB. Milk current standard based on killing Listeria monocytogenes, Campylobacter sps, Salmonella and Escherichia coli O157:H7, Coxiella burnetti. HEAT EXCHANGER: 72 o C for 15 sec. Clicker Question:

10. HTST Pasteurization – Continuous Counter Current Flow Counter- current Heat Exchanger Clicker Question:

11. Small Heat Exchanger

12. Heat Exchanger Diagram

13. Ultrapasteurization Heat Exchanger : heats milk to 138 o C for 3 sec (2 to 4 sec). Ultrapasteruized milk is supposed to last 6 months at room temperature without spoilage. Milk is packaged in plasticized cardboard containers. There’s a Story Here.

14. The Autoclave and water !

15. Ultra Violet Lights Are ON Clicker Question: The mesh work at the back holds behind it a HEPA Filter so that sterile air moves outward as a laminar flow.

16. Radiation Kills Just Like Heat 1 Gray (Gy) = 100 rads 1 rad = 100 ergs/g

17. Decimal Reduction Doses of Ionizing Radiation Check out the D 10 for humans

18. Clicker Question:

19. It Works Beautifully with Food

20. Filtration Depth Filters Membrane Filters Nucleopore Filters.

21. Bacteria stuck on membrane filters. Clicker Question:

22. Membrane Filtration Clicker Question:

23. Antimicrobial Chemical Effects

24. Minimal Inhibitory Concentration Lowest Concentrations    Highest Concentrations We did these with microtiter plates in Chapter 31 (Fig 31.8)

26. Antiseptics

28. Antimicrobial Agents Used In Vivo Clicker Question:

29. Antimicrobial Spectra Clicker Question:

30. Antibiotic Production Today

31. Salvarsan and Paul Ehrlich Clicker Question:

32. Sulfa Drugs: Gerhard Domagk, 1930’s First Chemosynthetic Antibiotics

33. Nucleoside Analogs First ones were simple, more complex one developed in response the AID’s epidemic.

34. Quinolones Ciprofloxacin Moxifloxacin Clicker Question:

35. Naturally Occurring Antimicrobials: The Antibiotics

36. β-lactamase Resistant Ceftriaxone A Cephalosporin

37. The Amino Glycosides: Target 30S ribosome

38. The Macrolides : Eythromycin Targets the 50S ribosome

39. The Tetracyclines : Targets 30 S ribosome

40. Daptomycin and Platensimycin Cyclic Lipopeptide: alters Cell Membranes Inhibits Fatty Acid biosynthesis

44. Antibiotic Resistance Antibiotic Resistance Mechanisms 1.Lacks structure antibiotic inhibits. 2.Impermeability. 3.Enzyme that alters structure of antibiotic. 4.Makes modification of antibiotic target. 5.Develops a resistant, alternate pathway. 6.Efflux Pump.

45. The Classics !

47. Epidemiological Patterns of Antibiotic Resistance

48. Appearance of Drug Resistance

49. Resistance to Vancomycin over come by converting the carbonyl to a methyl.

50. Computer Aided Drug Design

51. Other Antimicrobial Strategies Natural Products  searches for fit into prokaryotic essential enzymes from databases of plant or other organisms secondary products. This is how Platensimycin was discovered by a screen of 250,000 known bio-products. Drug Combinations  Augmentin is a combo drug containing amoxicillin and the β-lactamase inhibitor Clavulanic acid. See next slide.

52. Textbook Combo: Sulbactam and Ampicillin Clicker Question:

53. Augmentin = Clavamox = Tyclav Amoxicillin Clavunlanic Acid