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Future Microbiology Nov 2019To study physiological and proteomic analysis of grown under iron-limited condition. One clinical and environmental isolates grown under iron-depleted conditions...
To study physiological and proteomic analysis of grown under iron-limited condition. One clinical and environmental isolates grown under iron-depleted conditions were studied for siderophore production, ability to kill nematodes and alteration in protein expression using isobaric tags for relative and absolute quantification (ITRAQ). Siderophore production was observed in both clinical and environmental strains under iron-depleted conditions. assay showed higher killing rate under iron-depleted (96%) compared with normal condition (76%). The proteins identified revealed, 96 proteins upregulated and 26 proteins downregulated for the two isolates under iron depletion. The upregulated proteins included several iron acquisition proteins, metabolic proteins and putative virulence proteins.
Topics: Animals; Bacterial Proteins; Caenorhabditis elegans; Environmental Microbiology; Gram-Negative Bacterial Infections; Iron; Proteome; Siderophores; Stenotrophomonas maltophilia; Stress, Physiological; Virulence; Virulence Factors
PubMed: 31777284
DOI: 10.2217/fmb-2019-0174 -
Journal of Inorganic Biochemistry Feb 2021Bacteria have developed multiple resistance mechanisms against the most used antibiotics. In particular, zinc-dependent metallo-β-lactamase producing bacteria are a...
Bacteria have developed multiple resistance mechanisms against the most used antibiotics. In particular, zinc-dependent metallo-β-lactamase producing bacteria are a growing threat, and therapeutic options are limited. Zinc chelators have recently been investigated as metallo-β-lactamase inhibitors, as they are often able to restore carbapenem susceptibility. We synthesized polypyridyl ligands, N,N'-bis(2-pyridylmethyl)-ethylenediamine, N,N,N'-tris(2-pyridylmethyl)-ethylenediamine, N,N'-bis(2-pyridylmethyl)-ethylenediamine-N-acetic acid (N,N,N'-tris(2-pyridylmethyl)-ethylenediamine-N'-acetic acid, which can form zinc(II) complexes. We tested their ability to restore the antibiotic activity of meropenem against three clinical strains isolated from blood and metallo-β-lactamase producers (Klebsiella pneumoniae, Enterobacter cloacae, and Stenotrophomonas maltophilia). We functionalized N,N,N'-tris(2-pyridylmethyl)-ethylenediamine with D-alanyl-D-alanyl-D-alanine methyl ester with the aim to increase bacterial uptake. We observed synergistic activity of four polypyridyl ligands with meropenem against all tested isolates, while the combination N,N'-bis(2-pyridylmethyl)-ethylenediamine and meropenem was synergistic only against New Delhi and Verona integron-encoded metallo-β-lactamase-producing bacteria. All synergistic interactions restored the antimicrobial activity of meropenem, providing a significant decrease of minimal inhibitory concentration value (by 8- to 128-fold). We also studied toxicity of the ligands in two normal peripheral blood lymphocytes.
Topics: Anti-Bacterial Agents; Bacteria; Bacterial Proteins; Chelating Agents; Drug Resistance, Bacterial; Drug Therapy, Combination; Enterobacter cloacae; Gram-Negative Bacteria; Humans; Klebsiella pneumoniae; Ligands; Meropenem; Microbial Sensitivity Tests; Pyridines; Stenotrophomonas maltophilia; Zinc; beta-Lactamase Inhibitors; beta-Lactamases
PubMed: 33285370
DOI: 10.1016/j.jinorgbio.2020.111315 -
Virus Research Aug 2021Stenotrophomonas maltophilia is a common conditional pathogen, and it is naturally resistant to most commonly used clinical antibiotics. The bacteriophage is considered...
Stenotrophomonas maltophilia is a common conditional pathogen, and it is naturally resistant to most commonly used clinical antibiotics. The bacteriophage is considered to be a potential antibiotic alternative for treating multi-drug-resistant bacteria. In this study, a bacteriophage BUCT555 was isolated from hospital sewage for lysing the clinical multi-drug resistant Stenotrophomonas maltophilia. Electron microscopy studies revealed this phage belongs to the Podoviridae family. The double-stranded DNA genome of bacteriophage BUCT555 is composed of 39,440 bp with a GC content of 61.43%. The genome contains 57 open reading frames, 14 of which had assigned functions, while no virulence related genes, antibiotic resistance genes or tRNA were identified. The burst size of BUCT555 was 204 pfu per infected cell. Structure proteins of bacteriophage BUCT555 generated by SDS-PAGE and HPLC-MS revealed that it contains seven proteins with molecular weight ranging from 19 to 89 kDa. BLASTn analysis showed that phage BUCT555 has 2% homology with other phages in NCBI database, suggesting BUCT555 is a new phage genus of Podoviridae that infects Stenotrophomonas maltophilia. Characterization of the bacteriophage BUCT555 enriches our knowledge about the diversity of Stenotrophomonas maltophilia bacteriophages.
Topics: Bacteriophages; Genome, Viral; Genomics; Open Reading Frames; Podoviridae; Stenotrophomonas maltophilia
PubMed: 34052250
DOI: 10.1016/j.virusres.2021.198465 -
PloS One 2018Stenotrophomonas maltophilia is found ubiquitously in the environment and is an important emerging nosocomial pathogen. S. maltophilia has been recently described as an...
Stenotrophomonas maltophilia is found ubiquitously in the environment and is an important emerging nosocomial pathogen. S. maltophilia has been recently described as an Amoebae-Resistant Bacteria (ARB) that exists as part of the microbiome of various free-living amoebae (FLA) from waters. Co-culture approaches with Vermamoeba vermiformis demonstrated the ability of this bacterium to resist amoebal digestion. In the present study, we assessed the survival and growth of six environmental and one clinical S. maltophilia strains within two amoebal species: Acanthamoeba castellanii and Willaertia magna. We also evaluated bacterial virulence properties using the social amoeba Dictyostelium discoideum. A co-culture approach was carried out over 96 hours and the abundance of S. maltophilia cells was measured using quantitative PCR and culture approach. The presence of bacteria inside the amoeba was confirmed using confocal microscopy. Our results showed that some S. maltophilia strains were able to multiply within both amoebae and exhibited multiplication rates up to 17.5 and 1166 for A. castellanii and W. magna, respectively. In contrast, some strains were unable to multiply in either amoeba. Out of the six environmental S. maltophilia strains tested, one was found to be virulent. Surprisingly, this strain previously isolated from a soil amoeba, Micriamoeba, was unable to infect both amoebal species tested. We further performed an assay with a mutant strain of S. maltophilia BurA1 lacking the efflux pump ebyCAB gene and found the mutant to be more virulent and more efficient for intra-amoebal multiplication. Overall, the results obtained strongly indicated that free-living amoebae could be an important ecological niche for S. maltophilia.
Topics: Amoeba; Real-Time Polymerase Chain Reaction; Stenotrophomonas maltophilia; Virulence
PubMed: 29401523
DOI: 10.1371/journal.pone.0192308 -
Research in Microbiology May 2016The occurrence of Stenotrophomonas maltophilia was monitored in organic amendments and agricultural soils from various sites in France and Tunisia. S. maltophilia was...
The occurrence of Stenotrophomonas maltophilia was monitored in organic amendments and agricultural soils from various sites in France and Tunisia. S. maltophilia was detected in horse and bovine manures, and its abundance ranged from 0.294 (±0.509) × 10(3) to 880 (±33.4) × 10(3) CFU (g drywt)(-1) of sample. S. maltophilia was recovered from most tested soil samples (104/124). Its abundance varied from 0.33 (±0.52) to 414 (±50) × 10(3) CFU (g drywt)(-1) of soil and was not related to soil characteristics. Antibiotic resistance properties of a set of environmental strains were compared to a clinical set, and revealed a high diversity of antibiotic resistance profiles, given both the numbers of resistance and the phenotypes. Manure strains showed resistance phenotypes, with most of the strains resisting between 7 and 9 antibiotics. While French soil strains were sensitive to most antibiotics tested, some Tunisian strains displayed resistance phenotypes close to those of clinical French strains. Screening for metal resistance among 66 soil strains showed a positive relationship between antibiotic and metal resistance. However, the prevalence of antibiotic resistance phenotypes in the studied sites was not related to the metal content in soil samples.
Topics: Animals; Anti-Bacterial Agents; Bacterial Load; Cattle; Colony Count, Microbial; Drug Resistance, Bacterial; France; Horses; Manure; Metals; Microbial Sensitivity Tests; Soil; Soil Microbiology; Stenotrophomonas maltophilia; Tunisia
PubMed: 26774914
DOI: 10.1016/j.resmic.2016.01.001 -
Frontiers in Cellular and Infection... 2020To study the molecular epidemiological characteristics of (SMA) isolated from patients in a pediatric teaching hospital in Shanghai so as to provide data for the...
To study the molecular epidemiological characteristics of (SMA) isolated from patients in a pediatric teaching hospital in Shanghai so as to provide data for the prevention and treatment of SMA. Non-repetitive SMA strains were isolated from patients from January 2013 to December 2014. The cloning characteristics were analyzed using multilocus sequence typing (MLST) and pulsed field gel electrophoresis (PFGE), and the drug resistance was determined using the Kirby-Bauer disk method. Virulence genes and biofilm genes were detected using polymerase chain reaction (PCR). The biofilm forming ability was analyzed using the semi-quantitative biofilm formation test. A total of 104 strains were collected, primarily from the pediatric intensive care unit and thoracic surgery, and these strains were isolated from sputum sources ( = 82). A majority of the patients were male (67/104), and the age range was between 6 days and 12 years old. A total of 95 patients had 1-3 baseline diseases. All of the patients had prior use of 1-4 antimicrobial agents. A total of 59 STs were detected using the MLST analysis, of which 45 were new. The sequence types of the SMA were scattered, with no trend in the clonal spread. The PFGE showed that the 104 strains could be divided into 93 clusters, with no obvious cluster aggregations. All of the strains were susceptible to levofloxacin, trimethoprim/sulfamethoxazole, and minocycline. The positive rates of the virulence genes , and were 98.1, 86.5, 100, and 91.3%, respectively. All of the strains had biofilm formation, and most of the strains had strong biofilm formation abilities. The positive rates of the three biofilm genes , and were 83.7, 100, and 45.2%, respectively. However, the point mutations of and with strong biofilm formation abilities were significantly different from those with weak biofilm formation abilities. Most infected patients had prior use of antibiotics and underlying diseases, and the positive rate of the virulence gene was high. The strains were susceptible to three kinds of antibiotics and had strong biofilm formation abilities. The mutations of and may be related to the biofilm formation ability, and no obvious clonal transmissions were found in the same clinical department.
Topics: Anti-Bacterial Agents; Child; China; Female; Gram-Negative Bacterial Infections; Hospitals, Teaching; Humans; Male; Microbial Sensitivity Tests; Molecular Epidemiology; Multilocus Sequence Typing; Stenotrophomonas maltophilia
PubMed: 32850503
DOI: 10.3389/fcimb.2020.00411 -
Journal of Medical Microbiology Nov 2014Stenotrophomonas maltophilia is an important multidrug-resistant nosocomial pathogen associated with high mortality. Our aim was to examine antimicrobial susceptibility,...
Stenotrophomonas maltophilia is an important multidrug-resistant nosocomial pathogen associated with high mortality. Our aim was to examine antimicrobial susceptibility, biofilm production and clonal relatedness of clinical isolates of S. maltophilia. S. maltophilia isolates were collected between 2006 and 2013 from two tertiary care hospitals in Mexico. Antimicrobial susceptibility was evaluated by the broth microdilution method. PCR was used to determine the presence of β-lactamase genes L1 and L2. Biofilm formation was assessed with crystal violet staining. Clonal relatedness was determined by PFGE. Among the 119 collected S. maltophilia isolates, 73 (61.3%) were from the respiratory tract. Resistance levels exceeded 75% for imipenem, meropenem, ampicillin, aztreonam, gentamicin and tobramycin. Resistance to trimethoprim-sulfamethoxazole was 32.8%. L1 and L2 genes were detected in 77.1% (91/118) and 66.9% (79/118) of isolates, respectively. All S. maltophilia strains were able to produce biofilms. Strains were classified as weak (47.9%, 57/119), moderate (38.7%, 46/119), or strong (13.4%, 16/119) biofilm producers. A total of 89 distinct PFGE types were identified and 21.6% (22/102) of the isolates were distributed in nine clusters. This is the first study in Mexico to reveal characteristics of clinical isolates of S. maltophilia. Clonal diversity data indicate low cross-transmission of S. maltophilia in a hospital setting. The high antibiotic resistance underscores the need for continuous surveillance of S. maltophilia in hospital settings in Mexico.
Topics: Anti-Bacterial Agents; Biofilms; Genetic Variation; Gram-Negative Bacterial Infections; Humans; Mexico; Microbial Sensitivity Tests; Stenotrophomonas maltophilia
PubMed: 25165124
DOI: 10.1099/jmm.0.074385-0 -
Journal of Medical Microbiology Apr 2021As the representative multidrug-resistant pathogen, has multiple intrinsic and acquired resistances, including carbapenem resistance. In companion animals, the...
As the representative multidrug-resistant pathogen, has multiple intrinsic and acquired resistances, including carbapenem resistance. In companion animals, the antimicrobial susceptibility and sequence types (STs) of are not well understood due to its limited isolation rate. We investigated the antimicrobial susceptibilities and multilocus sequence types (MLSTs) of 38 . strains isolated from dogs and cats in Japan. Prevalence of resistance was detected for imipenem (100 %), aztreonam (94.7 %), piperacillin (65.8 %), trimethoprim-sulfamethoxazole (65.8 %), and ceftazidime (60.5 %). Rates of resistances to chloramphenicol, minocycline, and levofloxacin were low (2.6-5.3 %). MLST analysis revealed that all 38 strains were assigned to 34 STs, including 11 previously reported STs and 23 newly identified STs. Phylogenetic analysis of MLSTs enabled categorization of 13 isolates (34.2 %) into genogroup 6, which is a major genogroup of human isolates. Multinational surveillance would be needed to clarify the significance of antimicrobial-resistant isolates from companion animals.
Topics: Animals; Anti-Bacterial Agents; Cat Diseases; Cats; Dog Diseases; Dogs; Drug Resistance, Multiple, Bacterial; Genotype; Gram-Negative Bacterial Infections; Japan; Multilocus Sequence Typing; Stenotrophomonas maltophilia
PubMed: 33826489
DOI: 10.1099/jmm.0.001344 -
Viruses Jun 2021The isolation and characterization of bacteriophages for the treatment of infections caused by the multidrug resistant pathogen is imperative as nosocomial and... (Review)
Review
The isolation and characterization of bacteriophages for the treatment of infections caused by the multidrug resistant pathogen is imperative as nosocomial and community-acquired infections are rapidly increasing in prevalence. This increase is largely due to the numerous virulence factors and antimicrobial resistance genes encoded by this bacterium. Research on phages to date has focused on the isolation and in vitro characterization of novel phages, often including genomic characterization, from the environment or by induction from bacterial strains. This review summarizes the clinical significance, virulence factors, and antimicrobial resistance mechanisms of , as well as all phages isolated and characterized to date and strategies for their use. We further address the limited in vivo phage therapy studies conducted against this bacterium and discuss the future research needed to spearhead phages as an alternative treatment option against multidrug resistant .
Topics: Bacteriophages; Genome, Viral; Gram-Negative Bacterial Infections; Humans; Phage Therapy; Stenotrophomonas maltophilia; Virulence Factors
PubMed: 34204897
DOI: 10.3390/v13061057 -
Euro Surveillance : Bulletin Europeen... Jul 2016In April 2014, pulmonary Pseudomonas aeruginosa and Stenotrophomonas maltophilia co-infections potentially related to bronchoscopic procedures were identified in the...
In April 2014, pulmonary Pseudomonas aeruginosa and Stenotrophomonas maltophilia co-infections potentially related to bronchoscopic procedures were identified in the intensive care units of a university hospital in Lyon, France. A retrospective cohort of 157 patients exposed to bronchoscopes from 1 December 2013 to 17 June 2014 was analysed. Environmental samples of suspected endoscopes were cultured. Bronchoscope disinfection was reviewed. Ten cases of pulmonary P. aeruginosa/S. maltophilia co-infections were identified, including two patients with secondary pneumonia. Eight cases were linked to bronchoscope A1 and two to bronchoscope A2. Cultures deriving from suction valves were positive for P. aeruginosa/S. maltophilia. Exposure to bronchoscopes A1 and A2 was independently coupled with increased risk of co-infection (adjusted odds ratio (aOR) = 84.6; 95% confidence interval (CI): 9.3-771.6 and aOR = 11.8, 95% CI: 1.2-121.3). Isolates from suction valves and clinical samples presented identical pulsotypes. The audit detected deficiencies in endoscope disinfection. No further cases occurred after discontinuation of the implicated bronchoscopes and change in cleaning procedures. This outbreak of pulmonary P. aeruginosa/S. maltophilia co-infections was caused by suction valve contamination of two bronchoscopes of the same manufacturer. Our findings underscore the need to test suction valves, in addition to bronchoscope channels, for routine detection of bacteria.
Topics: Adult; Aged; Bronchoscopes; Coinfection; Disease Outbreaks; Equipment Contamination; France; Gram-Negative Bacterial Infections; Humans; Middle Aged; Molecular Typing; Pseudomonas Infections; Pseudomonas aeruginosa; Stenotrophomonas maltophilia
PubMed: 27458712
DOI: 10.2807/1560-7917.ES.2016.21.28.30286