Phenotypic Characterization of ESBL, AmpC and MBL Producers among the Clinical Isolates of Multidrug Resistant Pseudomonas aeruginosa

ABSTRACT We report here the characterization of a novel aminoglycoside resistance gene, aac(6′)-Iaf, present in two multidrug-resistant (MDR) Pseudomonas aeruginosa clinical isolates. These isolates, IMCJ798 and IMCJ799, were independently obtained from two patients, one with a urinary tract infection and the other with a decubitus ulcer, in a hospital located in the western part of Japan. Although the antibiotic resistance profiles of IMCJ798 and IMCJ799 were similar to that of MDR P. aeruginosa IMCJ2.S1, which caused outbreaks in the eastern part of Japan, the pulsed-field gel electrophoresis patterns for these isolates were different from that for IMCJ2.S1. Both IMCJ798 and IMCJ799 were found to contain a novel chromosomal class 1 integron, In123, which included aac(6′)-Iaf as the first cassette gene. The encoded protein, AAC(6′)-Iaf, was found to consist of 183 amino acids, with 91 and 87% identity to AAC(6′)-Iq and AAC(6′)-Im, respectively. IMCJ798, IMCJ799, and Escherichia coli transformants carrying a plasmid containing the aac(6′)-Iaf gene and its upstream region were highly resistant to amikacin, dibekacin, and kanamycin but not to gentamicin. The production of AAC(6′)-Iaf in these strains was confirmed by Western blot analysis. Thin-layer chromatography indicated that AAC(6′)-Iaf is a functional acetyltransferase that specifically modifies the amino groups at the 6′ positions of aminoglycosides. Collectively, these findings indicate that AAC(6′)-Iaf contributes to aminoglycoside resistance.

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Molecular characterization of multidrug resistant Klebsiella pneumoniae clinical isolates recovered from King Abdulaziz Specialist Hospital at Taif City, Saudi Arabia

Journal of Infection and Public Health ◽

10.1016/j.jiph.2020.12.001 ◽

2021 ◽

Vol 14 (1) ◽

pp. 143-151

Author(s):

Rihab Lagha ◽

Fethi Ben Abdallah ◽

Asmaa A.H. ALKhammash ◽

Nabil Amor ◽

Mohamed M. Hassan ◽

...

Keyword(s):

Saudi Arabia ◽

Klebsiella Pneumoniae ◽

Molecular Characterization ◽

Multidrug Resistant ◽

Clinical Isolates

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Detection of Extended-Spectrum β-Lactamases in Clinical Isolates of Pseudomonas aeruginosa

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01511-05 ◽

2006 ◽

Vol 50 (9) ◽

pp. 2990-2995 ◽

Cited By ~ 70

Author(s):

Xiaofei Jiang ◽

Zhe Zhang ◽

Min Li ◽

Danqiu Zhou ◽

Feiyi Ruan ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Multidrug Resistant ◽

Clinical Isolates ◽

Screening Methods ◽

Extended Spectrum ◽

Pcr Product ◽

Amoxicillin Clavulanate ◽

Synergy Test ◽

Esbl Producers ◽

Disk Test

ABSTRACT With the occurrence of extended-spectrum β-lactamases (ESBLs) in Pseudomonas aeruginosa being increasingly reported worldwide, there is a need for a reliable test to detect ESBLs in clinical isolates of P. aeruginosa. In our study, a total of 75 clinical isolates of P. aeruginosa were studied. Nitrocefin tests were performed to detect the β-lactamase enzyme; isoelectric focusing electrophoresis, PCR, and PCR product sequencing were designed to further characterize the contained ESBLs. Various ESBL-screening methods were designed to compare the reliabilities of detecting ESBLs in clinical isolates of P. aeruginosa whose β-lactamases were well characterized. Thirty-four of 36 multidrug-resistant P. aeruginosa clinical isolates were positive for ESBLs. bla VEB-3 was the most prevalent ESBL gene in P. aeruginosa in our study. Among the total of 34 isolates that were considered ESBL producers, 20 strains were positive using conventional combined disk tests and 10 strains were positive using a conventional double-disk synergy test (DDST) with amoxicillin-clavulanate, expanded-spectrum cephalosporins, aztreonam, and cefepime. Modifications of the combined disk test and DDST, which consisted of shorter distances between disks (20 mm instead of 30 mm) and the use of three different plates that contained cloxacillin (200 μg/ml) alone, Phe-Arg β-naphthylamide dihydrochloride (MC-207,110; 20 μg/ml) alone, and both cloxacillin (200 μg/ml) and MC-207,110 (20 μg/ml) increased the sensitivity of the tests to 78.8%, 91.18%, 85.29%, and 97.06%.

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Genotypic and phenotypic characterization of Pseudomonas aeruginosa isolates from urinary tract infections

International Journal of Medical Microbiology ◽

10.1016/j.ijmm.2010.10.005 ◽

2011 ◽

Vol 301 (4) ◽

pp. 282-292 ◽

Cited By ~ 25

Author(s):

Petra Tielen ◽

Maike Narten ◽

Nathalie Rosin ◽

Ilona Biegler ◽

Isam Haddad ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Urinary Tract ◽

Urinary Tract Infections ◽

Phenotypic Characterization ◽

Tract Infections

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Characterization of bacteriophages infecting clinical isolates of Pseudomonas aeruginosa stored in a culture collection

Brazilian Journal of Medical and Biological Research ◽

10.1590/1414-431x20132796 ◽

2013 ◽

Vol 46 (8) ◽

pp. 689-695 ◽

Cited By ~ 1

Author(s):

C.C.S. Zanetti ◽

R.C.C. Mingrone ◽

J.J. Kisielius ◽

M. Ueda-Ito ◽

A.C.C. Pignatari

Keyword(s):

Pseudomonas Aeruginosa ◽

Culture Collection ◽

Clinical Isolates

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Enhancement of pyocyanin production by subinhibitory concentration of royal jelly in Pseudomonas aeruginosa

F1000Research ◽

10.12688/f1000research.27915.3 ◽

2021 ◽

Vol 10 ◽

pp. 14

Author(s):

Dina Auliya Amly ◽

Puspita Hajardhini ◽

Alma Linggar Jonarta ◽

Heribertus Dedy Kusuma Yulianto ◽

Heni Susilowati

Keyword(s):

Pseudomonas Aeruginosa ◽

Bacterial Growth ◽

Biofilm Formation ◽

Royal Jelly ◽

Microtiter Plate ◽

Multidrug Resistant ◽

Clinical Isolates ◽

Antibiotic Tolerance ◽

Subinhibitory Concentration ◽

Pyocyanin Production

Background: Pseudomonas aeruginosa, a multidrug-resistant Gram-negative bacterium, produces pyocyanin, a virulence factor associated with antibiotic tolerance. High concentrations of royal jelly have an antibacterial effect, which may potentially overcome antibacterial resistance. However, in some cases, antibiotic tolerance can occur due to prolonged stress of low-dose antibacterial agents. This study aimed to investigate the effect of subinhibitory concentrations of royal jelly on bacterial growth, pyocyanin production, and biofilm formation of P. aeruginosa. Methods: Pseudomonas aeruginosa ATCC 10145 and clinical isolates were cultured in a royal jelly-containing medium to test the antibacterial activity. Pyocyanin production was observed by measuring the absorbance at 690 nm after 36 h culture and determined using extinction coefficient 4310 M-1 cm-1. Static microtiter plate biofilm assay performed to detect the biofilm formation, followed by scanning electron microscopy. Results: Royal jelly effectively inhibited the viability of both strains from a concentration of 25%. The highest production of pyocyanin was observed in the subinhibitory concentration group 6.25%, which gradually decreased along with the decrease of royal jelly concentration. Results of one-way ANOVA tests differed significantly in pyocyanin production of the two strains between the royal jelly groups. Tukey HSD test showed concentrations of 12.5%, 6.25%, and 3.125% significantly increased pyocyanin production of ATCC 10145, and the concentrations of 12.5% and 6.25% significantly increased production of the clinical isolates. Concentrations of 12.5% and 6.125% significantly induced biofilm formation of P. aeruginosa ATCC 10145, in line with the results of the SEM analysis. Conclusions: The royal jelly concentration of 25% or higher inhibits bacterial growth; however, the subinhibitory concentration increases pyocyanin production and biofilm formation in P. aeruginosa. It is advisable to determine the appropriate concentration of royal jelly to obtain beneficial virulence inhibiting activity.

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DNA microarray for genotyping multidrug-resistant Pseudomonas aeruginosa clinical isolates

Diagnostic Microbiology and Infectious Disease ◽

10.1016/j.diagmicrobio.2007.06.005 ◽

2007 ◽

Vol 59 (3) ◽

pp. 325-338 ◽

Cited By ~ 11

Author(s):

Jan Weile ◽

Rolf D. Schmid ◽

Till T. Bachmann ◽

Milorad Susa ◽

Cornelius Knabbe

Keyword(s):

Pseudomonas Aeruginosa ◽

Dna Microarray ◽

Multidrug Resistant ◽

Clinical Isolates

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First Detection of OXA-10 Extended-Spectrum Beta-Lactamases and the Occurrence of mexR and nfxB in Clinical Isolates of Pseudomonas aeruginosa from Nigeria

Chemotherapy ◽

10.1159/000441712 ◽

2015 ◽

Vol 61 (2) ◽

pp. 87-92 ◽

Cited By ~ 4

Author(s):

Bamidele T. Odumosu ◽

Bola A. Adeniyi ◽

Ram Chandra

Keyword(s):

Pseudomonas Aeruginosa ◽

Efflux Pump ◽

Clinical Isolates ◽

Beta Lactamases ◽

First Report ◽

Extended Spectrum ◽

Pcr Rflp ◽

Extended Spectrum Beta Lactamases ◽

Regulator Genes

Background: The characterization of β-lactamase production in Pseudomonasaeruginosa is rarely reported in Nigeria. The objective of this study was to investigate the occurrence and characterize the different β-lactamases as well as mechanisms of fluoroquinolones resistance among P. aeruginosa isolated from various clinical sources from Nigeria. Materials and Method: Isolates were investigated using PCR, RFLP and sequencing for the detection of various β-lactamases and efflux pump regulator genes. Result: The prevalence of OXA-10, AmpC, CTX-M and SHV in P. aeruginosa was 80, 70, 5 and 5%, respectively. The coexistence of blaOXA-10 with blaAmpC, blaSHV and blaCTX-M was reported in 40, 5 and 5% of isolates, respectively. The efflux pump regulator genes mexR and nfxB were both amplified in 45% of the OXA-10-positive isolates. Conclusion: This is the first report of the characterization of OXA-10 extended-spectrum β-lactamases and occurrence of mexR and nfxB efflux regulator genes in clinical isolates of P. aeruginosa in Nigeria.

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