scholarly journals Description of Two New Isolates ofStreptococcus pneumoniae in Spain That Are Highly Resistant to Cefotaxime

1998 ◽  
Vol 42 (10) ◽  
pp. 2768-2769 ◽  
Author(s):  
Joaquín Ruiz ◽  
Marco Sempere ◽  
Encarnación Simarro ◽  
Asunción Fenoll
Keyword(s):  
Streptococcus Pneumoniae ◽  
The Other ◽  
Resistance To Penicillin ◽  
High Level ◽  
Level Resistance

Two strains of Streptococcus pneumoniae isolated from sputum and bronchoalveolar samples with high-level resistance to cefotaxime (MIC = 8 to 16 μg/ml) are described. One of them, belonging to serogroup 19, was also highly resistant to penicillin (MIC = 16 μg/ml), while the other, of serogroup 14, was intermediate in its resistance to penicillin (MIC = 0.25 μg/ml). To our knowledge, these are the first two strains to be isolated in Spain with such high levels of resistance to cefotaxime.

Meningitis caused by Streptococcus pneumoniae showing high level resistance to penicillin

Pathology ◽  
1995 ◽  
Vol 27 (2) ◽  
pp. 165-167
Author(s):  
Keith A. Wise ◽  
Max Bedford ◽  
Surjit Singh Wadhwa ◽  
Ray Slobodniuk
Keyword(s):  
Streptococcus Pneumoniae ◽  
Resistance To Penicillin ◽  
High Level ◽  
Level Resistance

scholarly journals Dissemination of High-Level Penicillin-, Extended-Spectrum Cephalosporin-, and Erythromycin-Resistant Streptococcus pneumoniae Clones in Taiwan

1999 ◽  
Vol 37 (1) ◽  
pp. 221-224 ◽  
Author(s):  
Po-Ren Hsueh ◽  
Lee-Jene Teng ◽  
Li-Na Lee ◽  
Pan-Chyr Yang ◽  
Shen-Wu Ho ◽  
...  
Keyword(s):  
Streptococcus Pneumoniae ◽  
Random Amplified Polymorphic Dna ◽  
Penicillin Binding Protein ◽  
Extended Spectrum ◽  
Dna Restriction ◽  
Resistance To Penicillin ◽  
Arbitrarily Primed Pcr ◽  
High Level ◽  
Susceptibility Patterns ◽  
Level Resistance

Sixty-seven clinical isolates of Streptococcus pneumoniae (40 of serotype 23F, 19 of serotype 19F, and 8 of serotype 6B) with decreased susceptibilities to penicillin and erythromycin were characterized by antimicrobial susceptibility patterns; DNA restriction endonuclease cleavage profiles of the penicillin-binding protein genes pbp1a,pbp2b, and pbp2x; random amplified polymorphic DNA (RAPD) patterns generated by arbitrarily primed PCR; and chromosomal macrorestriction profiles based on pulsed-field gel electrophoresis. A total of 22 clones (identical or closely related pulsotypes and identical RAPD patterns) were identified; 14 clones of 23F, 6 of 19F, and 2 of 6B. Three 23F clones (26 isolates) and one 19F clone (9 isolates) expressed high-level resistance to penicillin, cefotaxime, and erythromycin (MICs ≥ 256 μg/ml). These data strongly suggest that multiple high-level penicillin-, extended-spectrum cephalosporin-, and macrolide-resistant clones ofS. pneumoniae have been disseminated in Taiwan.

scholarly journals Overexpression of the MtrC-MtrD-MtrE Efflux Pump Due to an mtrR Mutation Is Required for Chromosomally Mediated Penicillin Resistance in Neisseria gonorrhoeae

2002 ◽  
Vol 184 (20) ◽  
pp. 5619-5624 ◽  
Author(s):  
Wendy L. Veal ◽  
Robert A. Nicholas ◽  
William M. Shafer
Keyword(s):  
Neisseria Gonorrhoeae ◽  
Base Pair ◽  
Efflux Pump ◽  
Penicillin Resistance ◽  
Single Base ◽  
Base Pair Deletion ◽  
Resistance To Penicillin ◽  
Single Base Pair ◽  
High Level ◽  
Level Resistance

ABSTRACT The importance of the mtrCDE-encoded efflux pump in conferring chromosomally mediated penicillin resistance on certain strains of Neisseria gonorrhoeae was determined by using genetic derivatives of penicillin-sensitive strain FA19 bearing defined mutations (mtrR, penA, and penB) donated by a clinical isolate (FA6140) expressing high-level resistance to penicillin and antimicrobial hydrophobic agents (HAs). When introduced into strain FA19 by transformation, a single base pair deletion in the mtrR promoter sequence from strain FA6140 was sufficient to provide high-level resistance to HAs (e.g., erythromycin and Triton X-100) but only a twofold increase in resistance to penicillin. When subsequent mutations in penA and porIB were introduced from strain FA6140 into strain WV30 (FA19 mtrR) by transformation, resistance to penicillin increased incrementally up to a MIC of 1.0 μg/ml. Insertional inactivation of the gene (mtrD) encoding the membrane transporter component of the Mtr efflux pump in these transformant strains and in strain FA6140 decreased the MIC of penicillin by 16-fold. Genetic analyses revealed that mtrR mutations, such as the single base pair deletion in its promoter, are needed for phenotypic expression of penicillin and tetracycline resistance afforded by the penB mutation. As penB represents amino acid substitutions within the third loop of the outer membrane PorIB protein that modulate entry of penicillin and tetracycline, the results presented herein suggest that PorIB and the MtrC-MtrD-MtrE efflux pump act synergistically to confer resistance to these antibiotics.

scholarly journals Diversity of Substitutions within or Adjacent to Conserved Amino Acid Motifs of Penicillin-Binding Protein 2X in Cephalosporin-Resistant Streptococcus pneumoniaeIsolates

1999 ◽  
Vol 43 (5) ◽  
pp. 1252-1255 ◽  
Author(s):  
Yasuko Asahi ◽  
Yasuo Takeuchi ◽  
Kimiko Ubukata
Keyword(s):  
Streptococcus Pneumoniae ◽  
Amino Acid ◽  
Three Dimensional ◽  
Crystallographic Structure ◽  
Amino Acid Substitutions ◽  
Penicillin Binding Protein ◽  
Amino Acid Motif ◽  
Dna Fragment ◽  
High Level ◽  
Level Resistance

ABSTRACT The sequence of an approximately 1.1-kb DNA fragment of thepbp2x gene, which encodes the transpeptidase domain, was determined for 35 clinical isolates of Streptococcus pneumoniae for which the cefotaxime (CTX) MICs varied. Strains with substitutions within a conserved amino acid motif changing STMK to SAFK and a Leu-to-Val change just before the KSG motif were highly resistant to CTX (MIC, ≧2 μg/ml). Strains with substitutions adjacent to SSN or KSG motifs had low-level resistance. The amino acid substitutions were plotted on the three-dimensional crystallographic structure of the transpeptidase domain of PBP2X. Transformants containing pbp2x from strains with high-level CTX resistance increased the CTX MIC from 0.016 μg/ml to 0.5 to 1.0 μg/ml.

Inactivation of chloramphenicol by Gram-negative microorganisms

1968 ◽  
Vol 14 (8) ◽  
pp. 891-899 ◽  
Author(s):  
David Sompolinsky ◽  
Ruth Ziegler-Schlomowitz ◽  
Dora Herczog
Keyword(s):  
Escherichia Coli ◽  
Growth Medium ◽  
Minimal Medium ◽  
Resistance Factor ◽  
The Other ◽  
Gram Negative ◽  
Resistant Strains ◽  
Gram Negative Organisms ◽  
High Level ◽  
Level Resistance

Two derivative strains of Escherichia coli with high-level resistance to chloramphenicol, one carrying an episomal resistance factor and the other a chromosomal mutant, were both shown to be potent inactivators of the drug. When 1 mM chloramphenicol was added to an exponential culture in minimal medium, growth was halted until 85–90% of the drug was inactivated by acylation. At this state the drug was essentially monoacylated. During and after growth, esterification of the second alcoholic group occurred, though at a slower rate. Arylamines, in amounts up to 10% of chloramphenicol equivalents, were demonstrated in the growth medium after 1–3 days' incubation.With an acetateless mutant of Escherichia coli K12, carrying a resistance factor, it was shown that 5–6 moles of acetate was consumed for every mole of chloramphenicol acylated.Inactivation of chloramphenicol by Gram-negative organisms from infections in hospitalized patients was also examined. Among 103 strains susceptible to chloramphenicol, none produced considerable amounts of chloramphenicol esters. The same was the case with 14 resistant strains of Pseudomonas. Of 134 other resistant organisms examined, including strains of Escherichia, Proteus, Klebsiella, Salmonella, and Shigella, 133 were producers of chloramphenicol esters, and in most cases the drug was partly or entirely diacylated.

scholarly journals Genetic Characterization of Fluoroquinolone-Resistant Streptococcus pneumoniae Strains Isolated during Ciprofloxacin Therapy from a Patient with Bronchiectasis

2003 ◽  
Vol 47 (4) ◽  
pp. 1419-1422 ◽  
Author(s):  
Adela G. de la Campa ◽  
María-José Ferrandiz ◽  
Fe Tubau ◽  
Román Pallarés ◽  
Federico Manresa ◽  
...  
Keyword(s):  
Streptococcus Pneumoniae ◽  
Genetic Characterization ◽  
Susceptible Strain ◽  
Low Level ◽  
Resistant Strains ◽  
Resistant Mutants ◽  
High Level ◽  
Level Resistance

ABSTRACT Five Spain9V-3 Streptococcus pneumoniae strains were isolated from a patient with bronchiectasis who had received long-term ciprofloxacin therapy. One ciprofloxacin-susceptible strain was isolated before treatment, and four ciprofloxacin-resistant strains were isolated during treatment. The resistant strains were derived from the susceptible strain either by a parC mutation (low-level resistance) or by parC and gyrA mutations (high-level resistance). This study shows that ciprofloxacin therapy in a patient colonized by susceptible S. pneumoniae may select fluoroquinolone-resistant mutants.

scholarly journals Infective Endocarditis Complicated with Progressive Heart Failure due to β-Lactamase-Producing Cardiobacterium hominis

2000 ◽  
Vol 38 (5) ◽  
pp. 2015-2017 ◽  
Author(s):  
Po-Liang Lu ◽  
Po-Ren Hsueh ◽  
Chien-Ching Hung ◽  
Lee-Jene Teng ◽  
Tsrang-Neng Jang ◽  
...  
Keyword(s):  
Heart Failure ◽  
Congestive Heart Failure ◽  
Infective Endocarditis ◽  
Aortic Valve ◽  
Blood Isolate ◽  
Severe Aortic Regurgitation ◽  
Progressive Heart Failure ◽  
Resistance To Penicillin ◽  
High Level ◽  
Level Resistance

We describe a 66-year-old woman with infective endocarditis due toCardiobacterium hominis whose condition, complicated by severe aortic regurgitation and congestive heart failure, necessitated aortic valve replacement despite treatment with ceftriaxone followed by ciprofloxacin. The blood isolate of C. hominis produced β-lactamase and exhibited high-level resistance to penicillin (MIC, ≧256 μg/ml) and reduced susceptibility to vancomycin (MIC, 8 μg/ml).

scholarly journals Emergence in France of Multiple Clones of ClinicalStreptococcus pneumoniae Isolates with High-Level Resistance to Amoxicillin

1999 ◽  
Vol 43 (6) ◽  
pp. 1480-1483 ◽  
Author(s):  
Catherine Doit ◽  
Chawki Loukil ◽  
Frederic Fitoussi ◽  
Pierre Geslin ◽  
Edouard Bingen
Keyword(s):  
Streptococcus Pneumoniae ◽  
Genetic Relatedness ◽  
Molecular Fingerprinting ◽  
High Level ◽  
Level Resistance

ABSTRACT The genetic relatedness of French isolates of Streptococcus pneumoniae highly resistant to amoxicillin (MIC, ≥4 μg/ml, equal to or exceeding those of penicillin) was investigated by molecular fingerprinting. The results suggest that high-level resistance to amoxicillin has emerged within preexisting penicillin-resistant clones.

Sign in / Sign up

Export Citation Format

Share Document