Abstract
Mechanisms of ceftriaxone resistance were examined in Enterobacter cloacae. Clones were selected from four strains: susceptible (S), resistant (R1), selected by plating on ceftriaxone-containing agar, and highly resistant (R2), selected in ceftriaxone-treated mice infected with S clones. According to 14C-labeled beta-lactam binding assays, ceftriaxone resistance was not associated with altered target proteins. R1 and R2 clones stably produced 50 to 1,500 times more beta-lactamase than S clones; this production increased after cefoxitin induction in all S and some R1 clones. Experiments conducted with strain 218 suggested that ceftriaxone resistance involved beta-lactamase hydrolysis. Half-lives for the beta-lactamase-beta-lactam complexes at 37 degrees C were 0.4 and 2.2 min for ceftriaxone and Sch 34343, a drug not affected by the resistance, respectively; in chromatography experiments, 218 intact R1 cells (2 x 10(9) to 3 x 10(9) CFU) suspended in ceftriaxone-containing buffer (2 micrograms/ml) hydrolyzed 80% of the antibiotic in 30 min. Three observations also suggested decreased permeability in some clones, (i) Most of the R1 and R2 clones showed decreased expression of outer membrane proteins of 37,000 to 38,000 molecular weight (37K to 38K proteins) by electrophoresis, often associated with increased amounts of 42K protein. (ii) [14C]Sch 34343 labeling of intact cells proceeded more slowly in 218 R2 (with altered 37K to 38K proteins) than in 218 R1 (without this alteration), a difference persisting after competition with unlabeled cloxacillin. Delays in binding were not caused by different enzymatic activities, since 218 R1 and 218 R2 produce, in similar amounts, beta-lactamases undistinguishable in isoelectric point and Km of cephaloridine. (iii) Intact cells from 218 R2 hydrolyzed ceftriaxone more slowly (20% in 30 min) than did those from 218 R1. In 218 R1, beta-lactamase overproduction was responsible for a 15- to 200-fold increase in the MIC's of ceftriaxone, ceftazidime, carbenicillin, piperacillin, moxalactam, aztreonam, carumonam, and BMY 28142. Imipenem and Sch 34343 were not affected; an additional three- to fivefold increase in the MIC's of these antibiotics (with the exception of piperacillin, imipenem, Sch 34343), seen with 218 R2, was associated with decreased permeability.
Full text
PDF






Images in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Bonner W. M., Laskey R. A. A film detection method for tritium-labelled proteins and nucleic acids in polyacrylamide gels. Eur J Biochem. 1974 Jul 1;46(1):83–88. doi: 10.1111/j.1432-1033.1974.tb03599.x. [DOI] [PubMed] [Google Scholar]
- Bryson V., Szybalski W. Microbial Selection. Science. 1952 Jul 18;116(3003):45–51. doi: 10.1126/science.116.3003.45. [DOI] [PubMed] [Google Scholar]
- Bush K., Freudenberger J. S., Sykes R. B. Interaction of azthreonam and related monobactams with beta-lactamases from gram-negative bacteria. Antimicrob Agents Chemother. 1982 Sep;22(3):414–420. doi: 10.1128/aac.22.3.414. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bush K., Tanaka S. K., Bonner D. P., Sykes R. B. Resistance caused by decreased penetration of beta-lactam antibiotics into Enterobacter cloacae. Antimicrob Agents Chemother. 1985 Apr;27(4):555–560. doi: 10.1128/aac.27.4.555. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cartwright S. J., Waley S. G. Purification of beta-lactamases by affinity chromatography on phenylboronic acid-agarose. Biochem J. 1984 Jul 15;221(2):505–512. doi: 10.1042/bj2210505. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Curtis N. A., Orr D., Ross G. W., Boulton M. G. Competition of beta-lactam antibiotics for the penicillin-binding proteins of Pseudomonas aeruginosa, Enterobacter cloacae, Klebsiella aerogenes, Proteus rettgeri, and Escherichia coli: comparison with antibacterial activity and effects upon bacterial morphology. Antimicrob Agents Chemother. 1979 Sep;16(3):325–328. doi: 10.1128/aac.16.3.325. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Findell C. M., Sherris J. C. Susceptibility of Enterobacter to cefamandole: evidence for a high mutation rate to resistance. Antimicrob Agents Chemother. 1976 Jun;9(6):970–974. doi: 10.1128/aac.9.6.970. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Godfrey A. J., Bryan L. E., Rabin H. R. beta-Lactam-resistant Pseudomonas aeruginosa with modified penicillin-binding proteins emerging during cystic fibrosis treatment. Antimicrob Agents Chemother. 1981 May;19(5):705–711. doi: 10.1128/aac.19.5.705. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gootz T. D., Sanders C. C. Characterization of beta-lactamase induction in Enterobacter cloacae. Antimicrob Agents Chemother. 1983 Jan;23(1):91–97. doi: 10.1128/aac.23.1.91. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gutmann L., Williamson R., Moreau N., Kitzis M. D., Collatz E., Acar J. F., Goldstein F. W. Cross-resistance to nalidixic acid, trimethoprim, and chloramphenicol associated with alterations in outer membrane proteins of Klebsiella, Enterobacter, and Serratia. J Infect Dis. 1985 Mar;151(3):501–507. doi: 10.1093/infdis/151.3.501. [DOI] [PubMed] [Google Scholar]
- Kaneko M., Yamaguchi A., Sawai T. Purification and characterization of two kinds of porins from the Enterobacter cloacae outer membrane. J Bacteriol. 1984 Jun;158(3):1179–1181. doi: 10.1128/jb.158.3.1179-1181.1984. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kocher O., Skalli O., Cerutti D., Gabbiani F., Gabbiani G. Cytoskeletal features of rat aortic cells during development. An electron microscopic, immunohistochemical, and biochemical study. Circ Res. 1985 Jun;56(6):829–838. doi: 10.1161/01.res.56.6.829. [DOI] [PubMed] [Google Scholar]
- Lampe M. F., Allan B. J., Minshew B. H., Sherris J. C. Mutational enzymatic resistance of Enterobacter species to beta-lactam antibiotics. Antimicrob Agents Chemother. 1982 Apr;21(4):655–660. doi: 10.1128/aac.21.4.655. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Levine L. R., McCain E. Cefamandole in the treatment of infections due to Enterobacter and indole-positive Proteus. J Infect Dis. 1978 May;137 (Suppl):S125–S132. doi: 10.1093/infdis/137.supplement.s125. [DOI] [PubMed] [Google Scholar]
- Michéa-Hamzehpour M., Pechère J. C., Marchou B., Auckenthaler R. Combination therapy: a way to limit emergence of resistance? Am J Med. 1986 Jun 30;80(6B):138–142. doi: 10.1016/0002-9343(86)90491-2. [DOI] [PubMed] [Google Scholar]
- Nakamura K., Mizushima S. Effects of heating in dodecyl sulfate solution on the conformation and electrophoretic mobility of isolated major outer membrane proteins from Escherichia coli K-12. J Biochem. 1976 Dec;80(6):1411–1422. doi: 10.1093/oxfordjournals.jbchem.a131414. [DOI] [PubMed] [Google Scholar]
- O'Callaghan C., Morris A. Inhibition of beta-lactamases by beta-lactam antibiotics. Antimicrob Agents Chemother. 1972 Dec;2(6):442–448. doi: 10.1128/aac.2.6.442. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ross G. W., O'Callaghan C. H. Beta-lactamase assays. Methods Enzymol. 1975;43:69–85. doi: 10.1016/0076-6879(75)43081-6. [DOI] [PubMed] [Google Scholar]
- Sanders C. C., Moellering R. C., Jr, Martin R. R., Perkins R. L., Strike D. G., Gootz T. D., Sanders W. E., Jr Resistance to cefamandole: a collaborative study of emerging clinical problems. J Infect Dis. 1982 Jan;145(1):118–125. doi: 10.1093/infdis/145.1.118. [DOI] [PubMed] [Google Scholar]
- Sanders C. C., Sanders W. E., Jr Emergence of resistance to cefamandole: possible role of cefoxitin-inducible beta-lactamases. Antimicrob Agents Chemother. 1979 Jun;15(6):792–797. doi: 10.1128/aac.15.6.792. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sanders C. C., Sanders W. E., Jr Microbial resistance to newer generation beta-lactam antibiotics: clinical and laboratory implications. J Infect Dis. 1985 Mar;151(3):399–406. doi: 10.1093/infdis/151.3.399. [DOI] [PubMed] [Google Scholar]
- Sawai T., Hiruma R., Kawana N., Kaneko M., Taniyasu F., Inami A. Outer membrane permeation of beta-lactam antibiotics in Escherichia coli, Proteus mirabilis, and Enterobacter cloacae. Antimicrob Agents Chemother. 1982 Oct;22(4):585–592. doi: 10.1128/aac.22.4.585. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Seeberg A. H., Tolxdorff-Neutzling R. M., Wiedemann B. Chromosomal beta-lactamases of Enterobacter cloacae are responsible for resistance to third-generation cephalosporins. Antimicrob Agents Chemother. 1983 Jun;23(6):918–925. doi: 10.1128/aac.23.6.918. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Spratt B. G. Properties of the penicillin-binding proteins of Escherichia coli K12,. Eur J Biochem. 1977 Jan;72(2):341–352. doi: 10.1111/j.1432-1033.1977.tb11258.x. [DOI] [PubMed] [Google Scholar]
- Taylor R. K., Garrett S., Sodergren E., Silhavy T. J. Mutations that define the promoter of ompF, a gene specifying a major outer membrane porin protein. J Bacteriol. 1985 Jun;162(3):1054–1060. doi: 10.1128/jb.162.3.1054-1060.1985. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Then R. L., Angehrn P. Trapping of nonhydrolyzable cephalosporins by cephalosporinases in Enterobacter cloacae and Pseudomonas aeruginosa as a possible resistance mechanism. Antimicrob Agents Chemother. 1982 May;21(5):711–717. doi: 10.1128/aac.21.5.711. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Vu H., Nikaido H. Role of beta-lactam hydrolysis in the mechanism of resistance of a beta-lactamase-constitutive Enterobacter cloacae strain to expanded-spectrum beta-lactams. Antimicrob Agents Chemother. 1985 Mar;27(3):393–398. doi: 10.1128/aac.27.3.393. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Werner V., Sanders C. C., Sanders W. E., Jr, Goering R. V. Role of beta-lactamases and outer membrane proteins in multiple beta-lactam resistance of Enterobacter cloacae. Antimicrob Agents Chemother. 1985 Apr;27(4):455–459. doi: 10.1128/aac.27.4.455. [DOI] [PMC free article] [PubMed] [Google Scholar]


