Antibiotic Discovery Flashcards
First antimicrobial? Why?
Salvarsan, finding treatment for syphilis
Initial problems with penicillin? (2)
1) Difficult to purify
2) Hard to produce high yields
Define antibiotic
Natural or synthetic chemical substance that inhibits a type of microorganism within a host, without unacceptably interfering with the life of the host itself
Main difference between antimicrobial/antibiotic?
The effect on host
Discovery history of antibiotics (when, where)?
Mainly 1940s-1960s
Organisms in soil
New antibiotic action discovery?
Changing scaffold of existing antibiotic compounds
Methods of finding antibiotics? (2)
1) Sequence organism genome and express genes associated with antimicrobial production
2) Back produce from target in pathogen
Percentage of soil organisms cultured?
1%
Purpose of iChip?
Mimics natural environment - inoculated with soil and age and placed in soil to grow
Produce pure cultures - each hole traps one cell
New antibiotics found? (2)
1) Teixobactin - S. pneumoniae, MRSA, M. tuberculosis activity (no gm-neg). Inhibits peptidoglycan biosynthesis
2) Lugdunin - From S. lugdunensis, cyclic peptide. MRSA, VRE action (no gm neg)
Other methods of finding new antibiotics? Examples?
Revisiting existing compounds with undesirable toxicity profiles (fidaxomicin, daptomycin)
Method of overcoming antibiotic resistance?
Combination therapies
Politics of antibiotic development?
Make less money than chronic treatments, less incentive to produce
New antibiotics held for complicated cases
How many drugs get through trials? Current figure in trials?
1 in 5, 42 currently
What is the narrow spectrum era?
Rapid diagnosis to prevent empirical antibiotic use and slow resistance
