Human isolates of apramycin-resistant Escherichia coli which contain the genes for the AAC(3)IV enzyme

SUMMARYGentamicin-resistant Escherichia coli isolated at different periods from patients in two hospitals were tested for resistance to the aminoglycoside antibiotic apramycin. Twenty-four of 93 (26%) gentamicin-resistant isolates collected from the Royal Liverpool Hospital between 1981 and 1990 were resistant to apramycin. Thirteen isolates were highly resistant to apramycin (minimal inhibitory concentration (MIC) ≥ 1024 μg/ml). were also resistant to gentamicin, netilmicin and tobramycin, and hybridized with a DNA probe derived from the aminoglycoside acetyltransferase (3)IV (AAC(3)IV) gene. The proportion of gentamicinresistant isolates which had high level resistance to apramycin increased from 7% in 1981–5 to 24% in 1986–90.Twelve gentamicin-resistant E. coli from Guy's and St Thomas's Hospital isolated between 1977 and 1980 were also tested for resistance to apramycin. For five of these isolates the MICs of apramycin was 32–256 μg/ml. None was shown to have a conjugative plasmid carrying resistance to apramycin and only one hybridized with the DNA probe for the AAC(3)IV enzyme.

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Toxicity of the First Ten MEIC Chemicals to Bacteria

Alternatives to Laboratory Animals ◽

10.1177/026119299302100205 ◽

1993 ◽

Vol 21 (2) ◽

pp. 151-155

Author(s):

Gustaw Kerszman

Keyword(s):

Escherichia Coli ◽

Bacillus Subtilis ◽

Linear Regression ◽

Minimal Inhibitory Concentration ◽

Blood Concentration ◽

Inhibitory Concentration ◽

Human Lymphocytes ◽

Bacterial Species ◽

E Coli ◽

Mild Toxicity

The toxicity of the first ten MEIC chemicals to Escherichia coli and Bacillus subtilis was examined. Nine of the chemicals were toxic to the bacteria, with the minimal inhibitory concentration (MIC) ranging from 10-3 to 4.4M. The sensitivities of both organisms were similar, but the effect on E. coli was often bactericidal, while it was bacteriostatic for B. subtilis. Digoxin was not detectably toxic to either bacterial species. Amitriptyline and FeSO4 were relatively less toxic to the bacteria than to human cells. For seven chemicals, a highly significant linear regression was established between log MIC in bacteria and log of blood concentration, giving lethal and moderate/mild toxicity in humans, as well as with toxicity to human lymphocytes.

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Outbreak Caused by NDM-1- and RmtB-Producing Escherichia coli in Bulgaria

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02571-13 ◽

2014 ◽

Vol 58 (4) ◽

pp. 2472-2474 ◽

Cited By ~ 34

Author(s):

Laurent Poirel ◽

Encho Savov ◽

Arzu Nazli ◽

Angelina Trifonova ◽

Iva Todorova ◽

...

Keyword(s):

Escherichia Coli ◽

16S Rrna ◽

Sequence Type ◽

Content Type ◽

E Coli ◽

Carbapenem Resistant ◽

The World ◽

High Level ◽

16S Rrna Methylase ◽

Level Resistance

ABSTRACTTwelve consecutive carbapenem-resistantEscherichia coliisolates were recovered from patients (infection or colonization) hospitalized between March and September 2012 in different units at a hospital in Bulgaria. They all produced the carbapenemase NDM-1 and the extended-spectrum-β-lactamase CTX-M-15, together with the 16S rRNA methylase RmtB, conferring high-level resistance to all aminoglycosides. All those isolates were clonally related and belonged to the same sequence type, ST101. In addition to being the first to identify NDM-producing isolates in Bulgaria, this is the very first study reporting an outbreak of NDM-1-producingE. coliin the world.

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Plasmid-Mediated Resistance to Extended-Spectrum Cephalosporins and Resistance to Fluoroquinolones in Escherichia Coli Isolates from Black-headed Gulls (Larus Ridibundus)

10.21203/rs.3.rs-157826/v1 ◽

2021 ◽

Author(s):

Maja Velhner ◽

Dalibor Todorović ◽

Katarina Novović ◽

Branko Jovčić ◽

Gospava Lazić ◽

...

Keyword(s):

Escherichia Coli ◽

E Coli ◽

Extended Spectrum ◽

Cephalosporin Antibiotics ◽

High Level ◽

Group D ◽

Sequence Types ◽

Replicon Type ◽

Level Resistance ◽

Game Animals

Abstract Although resistance to fluoroquinolones is common in E. coli isolates from farm and game animals in Serbia, currently no data are accessible on the occurrence of antibacterial resistances in E. coli isolates from gulls. Therefore, 45 cloacal swabs and 50 fecal samples from black-headed gulls were investigated for the presence of Escherichia coli isolates resistant to antibiotics. Multidrug resistance was detected in 22 E. coli isolates. High level resistance to fluoroquinolones was found in ten isolates with MIC values of ciprofloxacin ranging from 4 to 32 mg/L. Genotyping revealed single or double mutations in the quinolone resistance determining region (QRDR) of the gyrA or gyrA, parC and parE genes, respectively. Ten isolates showed resistance to extended-spectrum cephalosporin antibiotics. These ten isolates belonged to phylogenetic group B2 (five isolates), group D (four isolates) and group B1 (one isolate). An extended-spectrum β-lactamase resistance phenotype was detected in one isolate which carried the blaCTX-M-1 gene on a plasmid of the I2/FIB replicon type. Nine isolates carried blaCMY-2 genes, which were detected on conjugative plasmids in seven isolates. One transconjugant also carried hly, iroN, iss, ompT and cvaC virulence genes on the plasmid. Five different sequence types (ST38, ST2307, ST224, ST162 and ST34) were detected in E. coli isolates with ESBL or AmpC phenotype and genotype.

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Identification of FosA8, a Plasmid-Encoded Fosfomycin Resistance Determinant from Escherichia coli, and Its Origin in Leclercia adecarboxylata

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01403-19 ◽

2019 ◽

Vol 63 (11) ◽

Cited By ~ 7

Author(s):

Laurent Poirel ◽

Xavier Vuillemin ◽

Nicolas Kieffer ◽

Linda Mueller ◽

Marie-Christine Descombes ◽

...

Keyword(s):

Escherichia Coli ◽

Amino Acid Identity ◽

Natural Resistance ◽

Whole Genome ◽

Content Type ◽

Acid Identity ◽

E Coli ◽

Fosfomycin Resistance ◽

High Level ◽

Level Resistance

ABSTRACT A plasmid-located fosfomycin resistance gene, fosA8, was identified from a CTX-M-15-producing Escherichia coli isolate recovered from urine. Identification of this gene was obtained by whole-genome sequencing. It encoded FosA8, which shares 79% and 78% amino acid identity with the most closely related FosA2 and FosA1 enzymes, respectively. The fosA8 gene was located on a transferable 50-kb plasmid of IncN type encoding high-level resistance to fosfomycin. In silico analysis and cloning experiments identified fosA8 analogues (99% identity) in the genome of Leclercia decarboxylata, which is an enterobacterial species with natural resistance to fosfomycin. This finding adds L. decarboxylata to the list of enterobacterial species that are a reservoir of fosA-like genes which have been captured from the chromosome of a progenitor and are then acquired by E. coli.

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Class A Carbapenemase FPH-1 from Francisella philomiragia

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00223-12 ◽

2012 ◽

Vol 56 (6) ◽

pp. 2852-2857 ◽

Cited By ~ 8

Author(s):

Marta Toth ◽

Viktoria Vakulenko ◽

Nuno T. Antunes ◽

Hilary Frase ◽

Sergei B. Vakulenko

Keyword(s):

Escherichia Coli ◽

Amino Acid ◽

Amino Acid Sequence Identity ◽

Content Type ◽

E Coli ◽

New Class ◽

Sequence Identity ◽

Class A ◽

High Level ◽

Level Resistance

ABSTRACTFPH-1 is a new class A carbapenemase fromFrancisella philomiragia. It produces high-level resistance to penicillins and the narrow-spectrum cephalosporin cephalothin and hydrolyzes these β-lactam antibiotics with catalytic efficiencies of 106to 107M−1s−1. When expressed inEscherichia coli, the enzyme confers resistance to clavulanic acid, tazobactam, and sulbactam and hasKivalues of 7.5, 4, and 220 μM, respectively, against these inhibitors. FPH-1 increases the MIC of the monobactam aztreonam 256-fold and the MIC of the broad-spectrum cephalosporin ceftazidime 128-fold, while the MIC of cefoxitin remains unchanged. MICs of the carbapenem antibiotics imipenem, meropenem, doripenem, and ertapenem are elevated 8-, 8-, 16-, and 64-fold, respectively, against anE. coliJM83 strain producing the FPH-1 carbapenemase. The catalytic efficiencies of the enzyme against carbapenems are in the range of 104to 105M−1s−1. FPH-1 is 77% identical to the FTU-1 β-lactamase fromFrancisella tularensisand has low amino acid sequence identity with other class A β-lactamases. Together with FTU-1, FPH-1 constitutes a new branch of the prolific and ever-expanding class A β-lactamase tree.

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High and low level tetracycline resistance inShigella sonnei

Journal of Hygiene ◽

10.1017/s0022172400053833 ◽

1978 ◽

Vol 81 (1) ◽

pp. 131-138 ◽

Cited By ~ 2

Author(s):

W. A. Hawkins ◽

J. W. Dale

Keyword(s):

Tetracycline Resistance ◽

Shigella Sonnei ◽

Conjugative Plasmid ◽

E Coli ◽

Low Level ◽

Variable Level ◽

High Level ◽

Level Resistance

SUMMARYThe results presented in this paper confirm the existence of two types of tetracycline resistance inShigella sonnei. One group of strains had a high level of resistance to tetracycline and oxytetracycline, with a variable level of minocycline resistance. The second group had a lower level of tetracycline resistance and were sensitive to minocycline. After conjugation withE. coliK12 the selectedE. colitransconjugants had the same levels of resistance as the parentSh. sonneistrain, with one exception.Sh. sonnei87 was resistant to a high level of tetracycline, but was able to transfer only low level resistance. It is suggested thatSh. sonnei87 carries two plasmids: pSU1, a conjugative plasmid conferring a low level of tetracycline resistance, and pSU2, a non-conjugative plasmid which confers a high level of resistance to tetracycline.

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Frequency and antimicrobial resistance of diarrhoeagenic Escherichia coli from young children in Iran

Journal of Medical Microbiology ◽

10.1099/jmm.0.064600-0 ◽

2014 ◽

Vol 63 (3) ◽

pp. 427-432 ◽

Cited By ~ 12

Author(s):

Fakhri Haghi ◽

Habib Zeighami ◽

Fahimeh Hajiahmadi ◽

Hakimeh Khoshvaght ◽

Marziyeh Bayat

Keyword(s):

Escherichia Coli ◽

Developing Countries ◽

Susceptibility Testing ◽

Multidrug Resistant ◽

Control Group ◽

E Coli ◽

Common Causes ◽

Stool Specimens ◽

High Level ◽

Level Resistance

Diarrhoea continues to be one of the most common causes of morbidity and mortality among infants and children in developing countries. Diarrhoeagenic Escherichia coli (DEC) is an emerging agent among pathogens that cause diarrhoea. Between March 2011 and January 2012, a total of 600 stool specimens from children younger than 5 years of age (450 with and 150 without diarrhoea) were investigated for enteroaggregative E. coli (EAEC), enterohaemorrhagic E. coli (EHEC), enteropathogenic E. coli (EPEC) and enterotoxigenic E. coli (ETEC) using PCR. Antimicrobial susceptibility testing was performed following Clinical and Laboratory Standards Institute guidelines. The prevalence of DEC pathotypes was 30.4 % (137 patients) and 12 % (18 patients) in the diarrhoea group and the control group, respectively. The most frequently isolated pathotype in diarrhoeal children was ETEC. This pathotype was detected significantly more often in children with diarrhoea (14.4 %) than in children without diarrhoea (5.3 %). EAEC and EPEC were detected with slightly higher frequencies in children with (8 and 4.2 %, respectively) than in children without (4.6 and 2 %, respectively) (P>0.05) diarrhoea. EHEC was only detected in children with diarrhoea (3.8 %). Of the children from the diarrhoea group, 10 % were colonized with more than one DEC pathotype. The DEC isolates exhibited high-level resistance to erythromycin (100 %), azteronam (80.7 %), amoxicillin (74.4 %) and tetracycline (69.3 %), and 86.4 % of isolates were multidrug resistant. In conclusion, ETEC continues to be an important agent associated with diarrhoea in children from Tabriz, Iran.

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Identification and Characterization ofaarF, a Locus Required for Production of Ubiquinone inProvidencia stuartii and Escherichia coli and for Expression of 2′-N-Acetyltransferase inP. stuartii

Journal of Bacteriology ◽

10.1128/jb.180.1.128-135.1998 ◽

1998 ◽

Vol 180 (1) ◽

pp. 128-135 ◽

Cited By ~ 41

Author(s):

David R. Macinga ◽

Gregory M. Cook ◽

Robert K. Poole ◽

Philip N. Rather

Keyword(s):

Escherichia Coli ◽

Regulation Of Gene Expression ◽

Open Reading Frames ◽

Mrna Levels ◽

E Coli ◽

Providencia Stuartii ◽

High Level ◽

Identification And Characterization ◽

Reading Frames ◽

Level Resistance

ABSTRACT Providencia stuartii contains a chromosomal 2′-N-acetyltransferase [AAC(2′)-Ia] involved in the O acetylation of peptidoglycan. The AAC(2′)-Ia enzyme is also capable of acetylating and inactivating certain aminoglycosides and confers high-level resistance to these antibiotics when overexpressed. We report the identification of a locus in P. stuartii, designated aarF, that is required for the expression of AAC(2′)-Ia. Northern (RNA) analysis demonstrated thataac(2′)-Ia mRNA levels were dramatically decreased in aP. stuartii strain carrying anaarF::Cm disruption. TheaarF::Cm disruption also resulted in a deficiency in the respiratory cofactor ubiquinone. The aarF locus encoded a protein that had a predicted molecular mass of 62,559 Da and that exhibited extensive amino acid similarity to the products of two adjacent open reading frames of unknown function (YigQ and YigR), located at 86 min on the Escherichia coli chromosome. AnE. coli yigR::Kan mutant was also deficient in ubiquinone content. Complementation studies demonstrated that theaarF and the E. coli yigQR loci were functionally equivalent. The aarF or yigQRgenes were unable to complement ubiD and ubiEmutations that are also present at 86 min on the E. colichromosome. This result indicates that aarF(yigQR) represents a novel locus for ubiquinone production and reveals a previously unreported connection between ubiquinone biosynthesis and the regulation of gene expression.

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