Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings PowerPoint ® Lecture Slide Presentation prepared by Christine L. Case M I C R O B I O L O G Y a n i n t r o d u c t i o n ninth edition TORTORA  FUNKE  CASE Part B 20 Antimicrobial Drugs

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Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Antiviral Drugs: Enzyme Inhibitors  Protease inhibitors  Indinavir  HIV  Inhibit attachment  Zanamivir  Influenza  Inhibit uncoating  Amantadine  Influenza  Interferons prevent spread of viruses to new cells  Viral hepatitis Figure 13.2b

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Antihelminthic Drugs  Niclosamide  Prevents ATP generation  Tapeworms  Praziquantel  Alters membrane permeability  Flatworms Figure 12.27

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Antihelminthic Drugs  Ivermectin  Paralyzes worm  Intestinal roundworms Figure 12.29a

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Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings E Test Figure  MIC: Minimal inhibitory concentration.  MBC: Minimal bactericidal concentration.

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Figure 20.20

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Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Antibiotic Resistance  Various mutations can lead to antibiotic resistance  Mechanisms of antibiotic resistance 1.Enzymatic destruction of drug. 2.Prevention of penetration of drug. 3.Alteration of drug's target site. 4.Rapid ejection of the drug.  Resistance genes are often on plasmids or transposons that can be transferred between bacteria.

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Antibiotic Resistance  Misuse of antibiotics selects for resistance mutants. Misuse includes:  Using outdated or weakened antibiotics.  Using antibiotics for the common cold and other inappropriate conditions.  Use of antibiotics in animal feed.  Failure to complete the prescribed regimen.  Using someone else's leftover prescription.

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Effects of Combinations of Drugs  Synergism  Antagonism