Negativ e mycoplas ma mycobacte ria cell wall

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Negativ e Mycoplas ma Mycobacte ria Cell Wall (Peptidoglycan) Synthesis Beta-Lactams (Penicillins and Cephalospori ns) Yes Penicillin s don't get through the outer membra ne Don't have cell walls at all Cell wall contains Mycolic Acid so that can be targeted in addition to Pepdidoglyc an Protein Synthesis Macrolides, Tetracyclines, and Streptogrami ns Yes Yes Yes Yes Cell Membrane Integrity Polymixins Usually only used topicall y Usually only used topically Usually only used topically Yes Usually only used topically Metabolism Sulfa drugs and trimethoprim Yes Yes Yes Yes 13
Dr. Wilk’s Note Guide for Microbiology Unit 11 Drug Target Major Classes of Antibiotics Gram- Positi ve Gram- Negativ e Mycoplas ma Mycobacte ria Nucleic Acid Synthesis Quinolones and Rifamycins Yes Yes Yes Rifampin is particularly good for Mycobacteri a due to its ability to penetrate tissues Mycolic Acid Synthesis/Integrat ion Isoniazid and Ethambutol Don't make mycoli c acid Don't make mycolic acid Don't make mycolic acid Yes Antifungal Drug Targets 1. Ergosterol- polyenes 2. DNA/RNA synthesis- azoles 3. Cell Wall Synthesis- beta glucan 4. Cell Division- microtubules Class of Drug Examples Effect on the Cell Use in Patients Special Considerations Polyenes Amphoterici n B punches holes in cell membrane by binding to ergosterol systemic mycoses toxicity issues Azoles Ketoconazol e Clotrimazol e Fluconazole inhibits ergosterol biosynthesi s dermatomycoses cutaneous mycoses systemic mycoses often available OTC Allylamines Terbinafine inhibits ergosterol biosynthesi azole-resistant mycoses 2nd line antifungal 14
Dr. Wilk’s Note Guide for Microbiology Unit 11 Class of Drug Examples Effect on the Cell Use in Patients Special Considerations s Griesofulvin Griesofulvin interferes with microtubul e assembly and mitosis superficial dermatophytic mycoses oral admin for dermatophytic mycoses Flucytosine Flucytosine inhibits RNA synthesis & eventually protein synthesis cutaneous mycoses kidney and bone marrow toxicity Echinocandi ns Capsofungi n inhibit cell- wall synthesis systemic mycoses in patients who are immunocompromi sed good for aspergillosis and candidiasis Drug Targets for Protozoa What are some challenges for targeting protozoa? protein synthesis can't be targeted because protozoan cells have 80s ribosomes like humans peptidoglycan synthesis can't be targeted because protozoans don't make it ergosterol synthesis can't be used as a target because only fungi make that Drug Group Examples Used to treat Target Consideratio ns Quinines Chloroquine Mefloquine Malaria Prevents the organism from metabolizin g heme Resistance Artemisinin Artemisinin- based combo Malaria Free radical formation Expensive 15
Dr. Wilk’s Note Guide for Microbiology Unit 11 Drug Group Examples Used to treat Target Consideratio ns therapies (ACTS) and oxidative stress Quinacrine Diiodohydroxyqu in Iodoquinol Giardiasis Cell membrane integrity Optic nerve toxicity Metronidazo le Flagyl Tinidazole Trichomonas and obligately anaerobic bacteria, giardiasis, amebiasis Anaerobic metabolism widely used Nitazoxanid e

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