Leakage of Periplasmic Enzymes From Cells of Heptose-Deficient Mutants of Escherichia Coli, Associated With Alterations in the Protein Component of the Outer Membrane

Singh, Akhand Pratap; Reithmeier, Reinhart A.F.

doi:10.2323/jgam.21.109

Cited by 14 publications

(10 citation statements)

References 13 publications

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“…The loss of LPS in the sensitive strain allowed a concomitant loss of some of the OM proteins and enzymes. Similar effects have been observed in OM of Salmonella typhimurium after the LPS underwent mutation25) or in heptose-deficient mutants of E. coli 26,27). From results of this and other studies we believe that the effect of PB on OM of S. marcescens is due to a summarizing multistep action of the antibiotic:…”

Section: Polyacrylamide Gel Electrophoresis Of Various Outer Membranesupporting

confidence: 75%

Chemical and electrophoretic changes induced by polymyxin B on outer membrane components from Serratia marcescens.

Brown

Tsang

1978

J. Antibiot.

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The effects of polymyxin B (PB) on outer membrane (OM) components from resistant (strain 08) and sensitive (strain Bizio) cells of Serratia marcescens were characterized by chemical analysis and polyacrylamide gel electrophoresis (PGE) in sodium dodecylsulfate. Chemical analysis revealed no major differences in the OM fractions after PB treatment of both strains, except for the loss of protein in PB treated OM of the sensitive strain. The yield and composition between the lipopolysaccharides (LPS) of the two strains were different both before and after treatment.PGE revealed that there was a complex formation between the LPS of resistant strain and PB but both dissociation and degradation occurred in the LPS components in the sensitive strain. In addition, it was found that the protein components were destabilized by PB with subsequent loss of some of the components from OM of the sensitive strain. The difference in the amount of LPS and their ability to complex with PB may reflect different degrees of antibiotic susceptibility of these two strains of S. marcescens. A sequential multistep mechanism is proposed for the action of PB on outer membranes of this species. ExperimentalWhole cells of S. marcescens strain 08 (PB resistant) and strain Bizio (PB sensitive) were grown and harvested as described earlier2).

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Section: Polyacrylamide Gel Electrophoresis Of Various Outer Membranesupporting

confidence: 75%

Chemical and electrophoretic changes induced by polymyxin B on outer membrane components from Serratia marcescens.

Brown

Tsang

1978

J. Antibiot.

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“…-' Activity was measured using glucose-6-phosphate as the substrate (20); unit of activity = micromoles of nicotinamide adenine dinucleotide phosphate reduced per minute at 25°C. defects in the outer membrane similarly show enhanced susceptibility to antibacterial agents and spontaneously release periplasmic enzymes (17) into the growth medium (5,18,24,25,(32)(33)(34)(35)38).…”

Section: Resultsmentioning

confidence: 99%

Unusual Susceptibility of Erwinia amylovora to Antibacterial Agents in Relation to the Barrier Function of its Cell Envelope

Chatterjee

Buss

Starr

1977

Antimicrob Agents Chemother

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Wild-type strains of the bacterial phytopathogen Erwinia amylovora (the cause of fire blight disease of apples and pears) are markedly susceptible to novobiocin, deoxycholate, and sodium dodecyl (= lauryl) sulfate. The inhibitory concentration, expressed as the concentration causing a 99% inhibition of growth, of these three antibacterial agents were 15 to 100, 40 to 800, and 50 to 800 μg/ml, respectively, depending on the E. amylovora strain. Growth of strains of other Erwinia spp. and Salmonella typhimurium is not affected at all, or is only slightly affected, at these concentrations. Introduction of the F′ lac + , RP1, and R100 drd -56 (but not E- lac + ) plasmids into an E. amylovora strain results in enhanced susceptibility to novobiocin and sodium dodecyl sulfate but not to deoxycholate. E. amylovora wild-type strains spontaneously release a periplasmic enzyme, cyclic phosphodiesterase, but not a cytoplasmic enzyme, glucose-6-phosphate dehydrogenase, into the growth medium. Addition of MgCl 2 (20 mM) and NaCl (84 mM) to tryptone broth stimulates the growth of wild-type E. amylovora strains and reduces or eliminates leakage of the periplasmic enzyme. Mutant strains of E. amylovora , selected for resistance to each separate antibacterial agent (or to all three of them), showed a direct correlation (in all but the novobiocin-resistant mutant) between drug resistance and reduced periplasmic leakiness. The relatively low maximum growth temperature (<37°C) of E. amylovora seems unrelated to periplasmic leakage, as judged from the inability of added MgCl 2 to raise the maximum growth temperature, although the generation time at 30°C is reduced from 108 to 54 min upon the addition of 20 mM MgCl 2 . The extensive leakage of periplasmic enzyme and unusual drug susceptibility of E. amylovora strains might stem from some defect(s) in some cell envelope component(s) other than the lipopolysaccharide of these bacteria (which contain the usual liposaccharide constituents).

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“…These consisted of the fol lowing: Escherichia coli strains R+TEM, TEM (cured), W3110, W3110 + RP1 R-factor, W3660, W3630 + RGN 238 R-factor; Enterobacter Cloacae P99, Klebsiella aerogenes K1 and their respective /?-lactamase-less mutants (provided by Glaxo Research Ltd., Greenford, Middlesex); E. coli K12 (Rl) supplied by Dr. N. Datta; and E. coli JE and its novobiocin-supersensitive mutants NS1, NS2 and NS3, provided by Dr. B. P. Singh [15].…”

Section: Methodsmentioning

confidence: 99%

Lytic Activity of a New Cephalosporin, Cefuroxime, against Gram-Negative Bacteria

Russell

Tottle

1978

Chemotherapy

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Cefuroxime, a new cephalosporin antibiotic, was inhibitory at low concentrations to several types of gram-negative bacteria. It was considerably more stable than cephaloridine or cephalothin to the β-lactamases produced by Escherichia coli (RP1), Klebsiella aerogenes K1 and Enterobacter cloacae P99. Concentrations of cefuroxime much greater than the minimum inhibitory concentration (MIC) were usually necessary to induce lysis of β-lactamase and non-β-lactamase producers. In contrast, cephaloridine, cephalothin and ampicillin were rapidly bacteriolytic at, or near, the respective MIC against non-β-lactamase producers, whereas the activity of these three antibiotics was considerably reduced against β-lactamase-producing strains.

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Leakage of Periplasmic Enzymes From Cells of Heptose-Deficient Mutants of Escherichia Coli, Associated With Alterations in the Protein Component of the Outer Membrane

Cited by 14 publications

References 13 publications

Chemical and electrophoretic changes induced by polymyxin B on outer membrane components from Serratia marcescens.

Chemical and electrophoretic changes induced by polymyxin B on outer membrane components from Serratia marcescens.

Unusual Susceptibility of Erwinia amylovora to Antibacterial Agents in Relation to the Barrier Function of its Cell Envelope

Lytic Activity of a New Cephalosporin, Cefuroxime, against Gram-Negative Bacteria

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