Antimicrobial drugs

Inhibition of cell wall synthesis

examples Penicillin, Cephalosporins, bacitracin, vancomycin/ prevents peptide interbridging

Penicillin

has a beta- Lactam ring that interferes with D-D transpeptidase that stops cell walls from being made.

Cephalosporins

also has a lactam ring that interferes with D-D transpeptidase

Bacitracin

inhibits cell wall synthesis at an earlier stage than penicillin by stopping the NAG and NAM building blocks across the membrane.

Vancomycin

has a narrow spectrum of effect limited to gram + bacteria/ is a glycopeptide and the last defense against MRSA

Inhibition of protein synthesis

Examples: Chloramphenicol,Streptomycin, Tetracyclines/ by stopping essential proteins from being made

Chloramphenicol

from Streptomyces venezuelae/ chemically made/ binds to the 50S ribosome subunit of bacteria and prevents formation of a peptide bond/ has a broad spectrum of use/ diffuses well in tissue due to small size/ SIDE EFFECT: suppression of bone marrow affecting RBC production.

Streptomycin

Isolated from Streptomyces griseus/ binds to the 30S ribosomal subunit of bacteria and interferes with the reading of mRNA/ effective against + and - gram bacteria and mycobacterium/ first effective treatment against TB/ SIDE EFFECTS: hearing and kidney damage

Tetracyclines

Isolated from Streptomyces aureofaciens/Binds to 30S ribosomal subunit of bacteria and interferes with docking of tRNA; blocking peptide synthesis/ Broad spectrum/ Diffuses well in most tissues/ Often have long retention times in the body/ SIDE EFFECTS: may suppress normal non-harmful microbiota leading to gastrointestinal upset or candida infections

Ethromycin

Isolated from Saccharopolyspora erythraea/ Binds to 50S ribosomal subunit blocking the peptide tunnel/ Effective against Gram+ bacteria/ SIDE EFFECTS: gastrointestinal upset

Linezolid

Completely synthetic drug / Binds to 50S ribosomal and prevents binding to 30S subunit (prevents formation of 70S ribosome)/ Effective against Gram+ bacteria/ Novel mechanism may help delay bacterial resistance/ Developed to help treat MRSA/ SIDE EFFECTS: diarrhea and headaches

Targeting the plasma membrane

making the bacteria suseptable to osmotic pressure.

Daptomycin

Isolated from Streptomyces roseosporus/ Attacks bacterial plasma membrane/ Changes membrane structure and stops DNA, RNA

protein synthesis./ Effective against Gram+ bacteria/ Useful against MRSA

Polymyxin B

Isolated from Bacillus polymyxa/ Binds and destalilizes both outer and cytoplasmic membrane of Gram- bacteria/ Topical use only, no prescription needed

Inhibition of nucleic acid synthesis

stops the creation of critiacal nucleic acids integral to the bacteria. Examples Rifamycins, Ciprofloxin

Rifamycins

Isolated from Amycolatopsis rifamycinica/ Inhibits synthesis of mRNA by binding to bacterial DNA-dependent RNA polymerase/ Highly diffusible molecule (tissue penetration)/Used to treat tuberculosis and leprosy (mycobacteria)/ SIDE EFFECTS: may damage the liver. urine, poop, and saliva might be colored red

Ciprofloxin

Chemical synthesized (not isolated from microbe)/ Inhibits bacterial DNA Gyrase blocking DNA replication/ Successive generations have led to a broader range drug/ Used to treat Anthrax/ SIDE EFFECTS: can cause tendon damage, nausea and diarrhea.

Sulfamethoxazole and Trimethoprim

Drug synergism (smaller dosage if two are combined)/ Inhibits the synthesis of metabolic intermediates of Thymidine (eventually inhibiting DNA synthesis)/ Often used to treat urinary tract infections (alternative to penicillin)/ SIDE EFFECTS: gastrointestinal upset

Amphotericin B

Isolated from m Streptomyces nodosus/ acts as an antifungal drug

Acyclovir

this drug makes it so the thymidine kinase fuses a phospate with a false nucleotide acylovir in virus infected cells.

Chloroquine

Used to treat and prevent Malaria/ Targets merozoites

Artemisinin

Used to treat and prevent Malaria/ Targets sporozoites

Niclosamide

Targets Tapeworms/ Prevents ATP generation

Praziquantel

Targets Flatworms and Flukes/ Alters membrane permeability

Ivermectin

Roundworms (some ticks and mites)/ Causes paralysis