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R Factor-Mediated and Chromosomal Resistance to Ampicillin in Escherichia coli
- Source :
- Antimicrobial Agents and Chemotherapy. 5:186-191
- Publication Year :
- 1974
- Publisher :
- American Society for Microbiology, 1974.
-
Abstract
- Sixty-four ampicillin-resistant strains of Escherichia coli were studied. Six characters were examined: (i) resistance to ampicillin, cephalothin, and carbenicillin, (ii) synergy between ampicillin and cloxacillin, (iii) level of β-lactamase activity after osmotic shock, (iv) transferability of ampicillin resistance, (v) immunological characterization of the enzyme, and (vi) determination of substrate profiles. One class of strains was found in which synthesis of β-lactamase is inferred to be plasmid mediated; these strains are highly resistant to ampicillin and carbenicillin, sensitive to cephalothin, do not show synergism between ampicillin and cloxacillin, and reveal a high enzymatic activity after osmotic shock. A second class is formed by strains for which β-lactamase synthesis is inferred to be chromosomal; these strains present a low resistance level to ampicillin, are sensitive to carbenicillin and resistant to cephalothin, show a synergism between ampicillin and cloxacillin, and reveal a very low enzymatic activity after osmotic shock. These characters may be used to differentiate periplasmic and cell-bound β-lactamases.
- Subjects :
- Pharmacology
Osmotic shock
Penicillin Resistance
Extrachromosomal Inheritance
Microbial Sensitivity Tests
Articles
Periplasmic space
biochemical phenomena, metabolism, and nutrition
Biology
Carbenicillin
medicine.disease_cause
Microbiology
Infectious Diseases
Cloxacillin
Plasmid
Amp resistance
Ampicillin
Escherichia coli
polycyclic compounds
medicine
Pharmacology (medical)
medicine.drug
Subjects
Details
- ISSN :
- 10986596 and 00664804
- Volume :
- 5
- Database :
- OpenAIRE
- Journal :
- Antimicrobial Agents and Chemotherapy
- Accession number :
- edsair.doi.dedup.....6d5d5839ef8f0c6a0e6973cc438219b1