Abstract / Description of output
The effects of mecillinam, ampicillin and cephalexin on peptidoglycan synthesis in Salmonella typhimurium 2616 have been studied at equivalent concentrations or "isoactivities". Using antibiotics at isoactivities allows a direct comparison of the biochemical effects of different antibiotics. When mecillinam was added at different times during the division cycle at a concentration that produced 50% inhibition of peptidoglycan synthesis in an exponential culture over a short period of time, the inhibition of synthesis was greatest in the newborn cells and least in the dividing cells. Antibiotic competition experiments showed that mecillinam preferentially bound to penicillin-binding protein 2 in S. typhimurium 2616. High performance liquid chromatography analysis of the residual peptidoglycan synthesized in the presence of mecillinam showed an unexpected increase in pentapeptides and a significant increase in cross-linking. Other antibiotics added at equivalent activities did not show an increase in cross-linking.
Original language | English |
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Pages (from-to) | 423-33 |
Number of pages | 11 |
Journal | Research in microbiology |
Volume | 144 |
Issue number | 6 |
Publication status | Published - Jul 1993 |
Keywords / Materials (for Non-textual outputs)
- Amdinocillin/pharmacology
- Ampicillin/pharmacology
- Bacterial Proteins
- Carrier Proteins
- Cell Division/drug effects
- Cephalexin/pharmacology
- Chromatography, High Pressure Liquid
- Depression, Chemical
- Hexosyltransferases/metabolism
- Multienzyme Complexes/metabolism
- Muramoylpentapeptide Carboxypeptidase
- Penicillin-Binding Proteins
- Peptidoglycan/analysis
- Peptidoglycan/biosynthesis
- Peptidyl Transferases/metabolism
- Salmonella typhimurium/cytology
- Salmonella typhimurium/drug effects
- Salmonella typhimurium/metabolism