Bacterial resistance to penicillins and cephalosporins

Smith, J. T.; Hamilton‐Miller, J. M. T.; Knox, Robert

doi:10.1111/j.2042-7158.1969.tb08267.x

Cited by 44 publications

(20 citation statements)

References 141 publications

(95 reference statements)

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“…This classification agrees in essential but not in details with the general classification of p-lactamases from Gram-negative bacteria proposed by some authors (Smith & HamiltonMiller, 1963;Ayliffe, 1965;Citri & Pollock, 1966;Sawai, Mitsuhashi & Yamagishi, 1968;Smith, Hamilton-Miller & Knox, 1969;Jack & Richmond, 1970).…”

Section: Discussionsupporting

confidence: 67%

Interaction between Carbenicillin and -Lactamases from Gram-negative Bacteria

Bobrowski¹,

Borowski²

1971

Journal of General Microbiology

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The rates of hydrolysis of carbenicillin and of other penicillins and cephalosporins by nine different P-lactamase preparations obtained from Gram-negative bacteria were compared. Enzymes produced by Klebsiella strains, most active against penicillins, as well as P-lactamases synthesized by Escherichia coli and Proteus tnirabilis strains hydrolysed carbenicillin, although at relatively lower rates than ampicillin or cephaloridine. In contrast, carbenicillin was extremely resistant to /3-lactamases with a predominant cephalosporinase activity as produced by Pseudomonus aeruginosa, Proteus vulgaris and Enterobacter strains. The cephalosporin P-lactamases activity of these enzymes was inhibited by carbenicillin. A considerably increased enzymic activity observed in one strain of Pseudomonas ueruginosa when grown in the presence of carbenicillin or other P-lactam antibiotics was unable to destroy carbenicillin to any measurable extent. A possible permeability barrier to carbenicillin has been demonstrated in some strains.

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Section: Discussionsupporting

confidence: 67%

Interaction between Carbenicillin and -Lactamases from Gram-negative Bacteria

Bobrowski¹,

Borowski²

1971

Journal of General Microbiology

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“…CHFmoTHF.R. (40). If the pa,tterns of such levels of resistance were sufficiently characteristic for certain mechanisms, it should be possible to infer prevalence of such mechanisms in large scale data from routine susceptibility testing.…”

Section: Resultsmentioning

confidence: 99%

“…The levels of resistance of the bacillus to differento f-lactam antibiotics, however, often do not correlate with the rates at which these antibiotics are hydrolyzed by the 6-lactamase released from disrupted bacilli (17,28,30,40). The ,-lactamase appears to act synergistically with other resistance mechanisms, such as permeability barriers to the entry into the bacillus of some antibiotics, in producing resistance to them (28,30,40). Thus, the particular ,B-lactamase together with the other resistance mechanisms that an isolate may possess appear to determine…”

mentioning

confidence: 99%

Characterization and Prevalence of the Different Mechanisms of Resistance to Beta-Lactam Antibiotics in Clinical Isolates of Escherichia coli

Medeiros

Kent

O’Brien

1974

Antimicrob Agents Chemother

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A survey of clinical isolates from a hospital laboratory showed that Escherichia coli could be grouped into three classes of beta-lactam-antibiotic resistance by results of routine susceptibility testing to ampicillin, cephalothin, and carbenicillin. E. coli highly resistant to ampicillin and carbenicillin but not to cephalothin (class I) were found to have one of two levels of R factor-mediated, periplasmic-,8-lactamase which resembled RTEM and was located behind a permeability barrier to penicillins but not to cephalosporins. This permeability barrier appeared to act synergistically with the ,B-lactamase in producing high levels of resistance to penicillins. E. coli highly resistant to ampicillin and cephalothin but not carbenicillin (class II) were found to have a ,8-lactamase with predominantly cephalosporinase activity which was neither transferable nor releasable by osmotic shock. E. coli moderately resistant to one or to all three of these antibiotics (class E) were found to have low levels of different ,8-lactamases including a transferable ,8-lactamase which resembled R,,,6. Thus, different mechanisms producing resistance to ,B-lactam antibiotics could be deduced from the patterns of resistance to ampicillin, cephalothin, and carbenicillin found on routine susceptibility testing. E. coli of class I were much more prevalent than the other classes and the proportion of E. coli that were class I increased with duration of patient hospitalization. The incidence of class I E. coli rose only slightly over the past 7 years and that of class II E. coli remained constant despite increased usage of both cephalothin and ampicillin. These observations emphasize that the properties of the apparently limited number of individual resistance mechanisms that exist in a bacterial flora, such as their genetic mobility and linkages and the spectrum of their antibiotic inactivating enzymes and permeability barriers, may govern the effect that usage of an antibiotic has upon the prevalence of resistance to it and to other antibiotics.

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“…The production of this enzyme renders the organisms less susceptible to the lethal action of penicillins and cephalosporins and may even lead to complete resistance to these antibiotics (14,15,17).…”

mentioning

confidence: 99%

Function of the Outer Membrane of Escherichia coli as a Permeability Barrier to Beta-Lactam Antibiotics

Zimmermann

Rosselet

1977

Antimicrob Agents Chemother

322

254

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On the basis of a simple theoretical model, the ease of penetration of f3-lactam antibiotics through the outer membrane ofEscherichia coli was measured. The cell envelope was found to act as a diffusion barrier to both penicillins and cephalosporins. The validity of the model and the cooperative action of cellbound f8-lactamase and outer membrane were further verified by comparing calculated and experimentally determined velocities of /8-lactam hydrolysis by intact cells and sonically treated cell suspensions. The results showed good correspondence at five different antibiotic concentrations. Similar conclusions could be drawn from a comparison of (3-lactam concentrations on both sides of the outer membrane, calculated from enzyme kinetic measurements and minimal inhibitory concentrations for both a (8-lactamase-producing E. coli and its enzyme-negative variant. in the case of benzylpenicillin and cephalothin, however, no correspondence was found. The joint action of several parameters determining the efficacy of penicillins and cephalosporins against 63-lactamaseproducing E. coli is discussed.Escherichia coli can carry extrachromosomal resistance determinants (R factors) mediating constitutive synthesis of 3-lactamase (EC 3.5.2.6). The production of this enzyme renders the organisms less susceptible to the lethal action of penicillins and cephalosporins and may even lead to complete resistance to these antibiotics (14, 15, 17).Whereas gram-positive 63-lactamase-producing organisms liberate their enzyme into the surrounding medium, the 3-lactamases of gram negative bacteria are compartmentalized (4,15). The fact that these enzymes can be totally released from E. coli by osmotic shock (8, 9) demonstrates that they are attached loosely to the cytoplasmic membrane or localized in the periplasm.Both f3-lactamases and the outer membrane are important factors in the resistance ofE. coli to penicillins and cephalosporins (1-3, 18). Conclusions regarding the ease of penetration of these antibiotics through the outer membrane, however, have mainly been drawn from comparisons of rates of hydrolysis by intact cells and sonically treated cell suspensions (6, 15). This determination alone is not sufficient to measure outer-membrane permeability.Given a periplasmic localization of 3-lactamase and assuming that both penicillins and

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Bacterial resistance to penicillins and cephalosporins

Cited by 44 publications

References 141 publications

Interaction between Carbenicillin and -Lactamases from Gram-negative Bacteria

Interaction between Carbenicillin and -Lactamases from Gram-negative Bacteria

Characterization and Prevalence of the Different Mechanisms of Resistance to Beta-Lactam Antibiotics in Clinical Isolates of Escherichia coli

Function of the Outer Membrane of Escherichia coli as a Permeability Barrier to Beta-Lactam Antibiotics

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