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Antimicrobial Agents and Chemotherapy Dec 2019We tested the activities of ceftazidime-avibactam, ceftolozane-tazobactam, meropenem-vaborbactam, piperacillin-tazobactam, and 11 other antimicrobial agents against 420...
We tested the activities of ceftazidime-avibactam, ceftolozane-tazobactam, meropenem-vaborbactam, piperacillin-tazobactam, and 11 other antimicrobial agents against 420 , , , and strains, 89% of which were cultured from respiratory specimens from persons with cystic fibrosis. Among the β-lactam-β-lactamase inhibitor agents, meropenem-vaborbactam had the greatest activity against and , including multidrug-resistant and extensively-drug-resistant strains. None of the newer β-lactam-β-lactamase combination drugs showed increased activity compared to that of the older agents against or spp.
Topics: Achromobacter; Anti-Bacterial Agents; Boronic Acids; Burkholderia; Cystic Fibrosis; Humans; Meropenem; Microbial Sensitivity Tests; Piperacillin; Pseudomonas aeruginosa; Stenotrophomonas; Stenotrophomonas maltophilia; Tazobactam; beta-Lactamase Inhibitors
PubMed: 31611364
DOI: 10.1128/AAC.01595-19 -
Bulletin of Environmental Contamination... Oct 2019The widespread use of bisphenol S (BPS) as a bisphenol A substitute increases its potential of release into the aquatic environments. However, the degradation of BPS in...
The widespread use of bisphenol S (BPS) as a bisphenol A substitute increases its potential of release into the aquatic environments. However, the degradation of BPS in aquatic systems is largely unknown, which will dictate its fate and toxicity. In this study, a bacterial consortium was enriched from river sediments and the dynamic changes of community structure during bacterial acclimation were studied. BPS degrading bacterial strains isolated from the consortium were identified by 16S rRNA analysis. The efficiency of the consortium and strains for BPS degradation were further evaluated. After 28 days of acclimation, the microbial diversity decreased significantly and four bacterial genera Hyphomicrobium, Pandoraea, Rhodococcus, and Cupriavidus with relative abundances of 5.1%-52.8% became dominant in the consortium. Total of two pure strains including Terrimonas pekingensis and Pseudomonas sp. were isolated from the consortium, using BPS as the sole carbon source. The consortium was highly efficient to degrade BPS, and 99% of BPS with an initial concentration of 50 mg/L was removed within 10 days at pH 7 and 30°C. In comparison with the consortium, a single strain cultures had lower BPS degradation efficiency. These findings indicate that BPS will degrade rapidly under aerobic conditions in river sediments and have implication for BPS-contaminated site remediation using the enriched consortium.
Topics: Bacteria; Benzhydryl Compounds; Biodegradation, Environmental; Geologic Sediments; Microbial Consortia; Phenols; Pseudomonas; RNA, Ribosomal, 16S; Rhodococcus; Rivers; Sulfones
PubMed: 31486911
DOI: 10.1007/s00128-019-02699-7 -
Italian Journal of Pediatrics Sep 2019Pandoraea species are gram negative, motile, non-spore forming, rod shaped and oxidase positive, obligate aerobes bacteria, and have one polar flagellum. Most of...
BACKGROUND
Pandoraea species are gram negative, motile, non-spore forming, rod shaped and oxidase positive, obligate aerobes bacteria, and have one polar flagellum. Most of Pandoraea species are associated with lung infections in cystic fibrosis patients. Cystic fibrosis is the most prevalent autosomal recessive hereditary disease in the world that affects various organs of the body. The main important cause of death in these patients is lung involvement. This study was conducted to isolate and identify Pandoraea bacterium from bronchoalveolar lavage and sputum samples of cystic fibrosis patients in Shiraz, Iran.
METHODS
In this research 31 samples of bronchoalveolar lavage and sputum were examined by culture and PCR method. Then confirmed isolates were evaluated for susceptibility to different antibiotics and ability to produce biofilm.
RESULTS
The results of this study after cultivation, purification and DNA extraction led to the isolation of 4 Pandoraea bacterium by PCR using specific primers. Antibiotic susceptibility test were indicated all isolates were resistant to gentamicin, amikacin and imipenem and susceptible to ciprofloxacin, trimethoprim-sulfumethoxazole, piperacillin and tetracycline. Ability to create biofilm was indicated by some of Pandoraea isolates. According to findings of this study, ability to synthesis biofilm by Pandoraea isolates and resistance to some antibiotics are very important.
CONCLUSIONS
Our study notes the role of P. pnomenusa as an emerging pathogen that can cause chronic lung colonization in CF patients. Identification tools need to be accurate and must be based on molecular techniques. Also our findings should raise awareness about antibiotic resistance in cystic fibrosis patients in Iran and ability of including bacterial agents to produce biofilm is an alarm for public health. Thus clinicians should exercise caution about finding of clinical relevance of this pathogen to the infection and prescribing antibiotics, especially in cases of children infections.
Topics: Bronchoalveolar Lavage Fluid; Burkholderiaceae; Child; Cystic Fibrosis; Female; Gram-Negative Bacterial Infections; Humans; Iran; Male; Respiratory Tract Infections; Sputum
PubMed: 31477148
DOI: 10.1186/s13052-019-0687-x -
Frontiers in Microbiology 2019The most common quorum sensing (QS) system in Gram-negative bacteria consists of signaling molecules called acyl-homoserine lactones (AHLs), which are synthesized by an...
The most common quorum sensing (QS) system in Gram-negative bacteria consists of signaling molecules called acyl-homoserine lactones (AHLs), which are synthesized by an enzyme AHL synthase (LuxI) and detected by a transcriptional regulator (LuxR) that are usually located in close proximity. However, many recent studies have also evidenced the presence of LuxR solos that are LuxR-related proteins in Proteobacteria that are devoid of a cognate LuxI AHL synthase. species are opportunistic pathogens frequently isolated from sputum specimens of cystic fibrosis (CF) patients. We have previously shown that strains possess QS activity. In this study, we examined the presence of QS activity in all type strains of species and acquired their complete genome sequences for holistic bioinformatics analyses of QS-related genes. Only four out of nine type strains (, , and ) showed QS activity, and C8-HSL was the only AHL detected. A total of 10 canonical s with adjacent s were predicted by bioinformatics from the complete genomes of aforementioned species and publicly available genomes. No orphan was identified in any of the genomes. However, genes for two LuxR solos (LuxR2 and LuxR3 solos) were identified in all genomes (except two draft genomes with one LuxR solo gene), and was the only species that harbored no QS-related activity and genes. Except the canonical LuxR genes, LuxIs and LuxR solos of species were distantly related to the other well-characterized QS genes based on phylogenetic clustering. LuxR2 and LuxR3 solos might represent two novel evolutionary branches of LuxR system as they were found exclusively only in the genus. As a few solos were located in close proximity with prophage sequence regions in the genomes, we thus postulated that these solos could be transmitted into genus by transduction process mediated by bacteriophage. The bioinformatics approach developed in this study forms the basis for further characterization of closely related species. Overall, our findings improve the current understanding of QS in species, which is a potential pharmacological target in battling infections in CF patients.
PubMed: 31447806
DOI: 10.3389/fmicb.2019.01758 -
Current Microbiology Nov 2019Chlorobenzenes are ubiquitously distributed, highly persistent, and toxic environmental contaminants. Pandoraea pnomenusa MCB032 was isolated as a new dominant...
Chlorobenzenes are ubiquitously distributed, highly persistent, and toxic environmental contaminants. Pandoraea pnomenusa MCB032 was isolated as a new dominant chlorobenzene-utilizing strain from a functionally stable bioreactor during the treatment of chlorobenzenes when strain Burkholderia sp. JS150 disappeared. In study, we report the complete genome sequence of strain MCB032 which consists of a circular chromosome and three plasmids, which are ~ 6 Mb in length with 5450 open reading frames-12 encoding rRNAs and 77 encoding tRNAs. We further identified 17 putative genes encoding the enzymes involved in the methyl-accepting chemotaxis proteins in sensing chemical gradients during chemotaxis. The annotated complete genome sequence of this strain will provide genetic insights into the degradation of chlorinated aromatic compounds. The information will empower the elucidation of chlorobenzene affinity hierarchy and species succession in the bioreactor.
Topics: Biodegradation, Environmental; Burkholderiaceae; Chlorobenzenes; Genome, Bacterial; Plasmids; Whole Genome Sequencing
PubMed: 31432211
DOI: 10.1007/s00284-019-01760-2 -
Scientific Reports Jul 2019Temperature, which is an important environmental factor in broiler farming, can significantly influence the deposition of fatty acids in muscle. 300 one-day-old broiler...
Temperature, which is an important environmental factor in broiler farming, can significantly influence the deposition of fatty acids in muscle. 300 one-day-old broiler chicks were randomly divided into three groups and reared at high, medium and low temperatures (HJ, MJ and LJ), respectively. Breast muscle and jejunal chyme samples were collected and subjected to analyses of fatty acid composition and 16S rRNA gene sequencing. Through spearman's rank correlation coefficient, the data were used to characterize the correlation between jejunal microbial diversity and muscle fatty acid deposition in the broilers. The results showed that Achromobacter, Stenotrophomonas, Pandoraea, Brevundimonas, Petrobacter and Variovorax were significantly enriched in the MJ group, and all of them were positively correlated with the fatty acid profiling of muscle and multiple lipid metabolism signaling pathways. Lactobacillus was significantly enriched in the HJ group and exhibited a positive correlation with fatty acid deposition. Pyramidobacter, Dialister, Bacteroides and Selenomonas were significantly enriched in the LJ group and displayed negative correlation with fatty acid deposition. Taken together, this study demonstrated that the jejunal microflora manifested considerable changes at high and low ambient temperatures and that jejunal microbiota changes were correlated with fatty acid deposition of muscle in broilers.
Topics: Animals; Chickens; Fatty Acids; Gastrointestinal Microbiome; Jejunum; Metagenome; Muscle, Skeletal; Temperature
PubMed: 31363155
DOI: 10.1038/s41598-019-47323-0 -
Journal of Medical Microbiology Jul 2019We examined evidence for transmission of Pandorea apista among cystic fibrosis (CF) patients attending paediatric and adult services in one city who had previously been...
PURPOSE
We examined evidence for transmission of Pandorea apista among cystic fibrosis (CF) patients attending paediatric and adult services in one city who had previously been found to harbour related isolates by pulsed-field gel electrophoresis (PFGE).
METHODOLOGY
The whole-genome sequences of 18 isolates from this cluster from 15 CF patients were examined, along with 2 cluster isolates from 2 other centres. The annotated sequence of one of these, Pa14367, was examined for virulence factors and antibiotic resistance-associated genes in comparison with data from a 'non-cluster' isolate, Pa16226.
RESULTS
Single-nucleotide polymorphism (SNP) analysis suggested that cluster isolates from the same city differed from one another by a minimum of 1 and a maximum of 383 SNPs (an average of 213 SNPs; standard deviation: 18.5), while isolates from the 2 other hospitals differed from these by a minimum of 34 and 61 SNPs, respectively. Pa16226 differed from all cluster isolates by a minimum of 22 706 SNPs. Evidence for patient-to-patient transmission among isolates from the same city was relatively limited, although transmission from a common source could not be excluded. The annotated genomes of Pa14367 and Pa16226 carried putative integrative and conjugative elements (ICEs), coding for type IV secretion systems, and genes associated with heavy metal degradation and carbon dioxide fixation, and a wide selection of genes coding for efflux pumps, beta-lactamases and penicillin-binding proteins.
CONCLUSION
Epidemiological analysis suggested that this cluster could not always be attributed to patient-to-patient transmission. The acquisition of ICE-related virulence factors may have had an impact on its prevalence.
Topics: Adult; Burkholderiaceae; Child; Cluster Analysis; Cystic Fibrosis; Genome, Bacterial; Gram-Negative Bacterial Infections; Humans; Phylogeny
PubMed: 31210630
DOI: 10.1099/jmm.0.001010 -
Chemosphere Sep 2019Our understanding of the tetrahydrofuran (THF) degradation in complex environment is limited. The majority of THF degrading genes reported are group V soluble diiron...
Our understanding of the tetrahydrofuran (THF) degradation in complex environment is limited. The majority of THF degrading genes reported are group V soluble diiron monooxygenases and share greater than 95% homology with one another. In this study, we used sole-carbon-source incubation combined with high-throughput metagenomic sequencing to investigate this contaminant's degradation in environmental samples. We identified as-yet-uncultivated microbe from the genera Pseudonocardia and fungi Scedosporium sp. (Scedosporium sp. was successfully isolated) as THF degraders as containing THF degradation genes, while microbes from the genera Bordetella, Pandoraea and Rhodanobacter functioned as main cooperators by utilizing acidic intermediates and providing anti-acid mechanisms. Furthermore, a 9387-bp THF degradation cluster designated thmX from the as-yet-uncultivated Pseudonocardia (with 6 main ORFs and with 79-93% amino acid sequence identity with previously reported clusters) was discovered. We also found a THF-degrading related cytochrome P450 monooxygenase from the genus Scedosporium and predicted its cognate reductase for the first time. All the genes and clusters mentioned above were successfully amplified from samples and cloned into the suitable expression vectors. This study will provide novel insights for understanding of THF degradation mechanisms under acid stress conditions and mining new THF degradation genes.
Topics: Actinomycetales; Furans; Metagenome; Metagenomics; Microbiota; Mixed Function Oxygenases; Open Reading Frames
PubMed: 31129398
DOI: 10.1016/j.chemosphere.2019.05.137 -
The Journal of General and Applied... Jan 2020Siderophores are considered to have a good potential as decontamination agents owing to their metal-chelating abilities. In order to confirm whether siderophores can be...
Siderophores are considered to have a good potential as decontamination agents owing to their metal-chelating abilities. In order to confirm whether siderophores can be used in the recovery of metal ions, a siderophore (or metallophore) exhibiting Co-chelating activity was screened to demonstrate its ability to recover Co from an aqueous solution. A siderophore-producing bacterium, Pandoraea sp. HCo-4B, was identified from a screen of Co-resistant bacteria grown in an aerobic enrichment culture with a Co-supplemented medium. After incubation of the crude extracted siderophore in a Co-containing solution, the Co-siderophore complex was adsorbed on to a C column. The bound Co was eluted from the column by the addition of 10 mM HSO. The recovered amount of Co was proportional to the amount of the added siderophore. We observed that the siderophore identified in this study binds to Co at a 1:1 ratio.
Topics: Burkholderiaceae; Cobalt; Culture Media; Siderophores
PubMed: 31019144
DOI: 10.2323/jgam.2018.12.001 -
Frontiers in Microbiology 2019Few bacteria are resistant to tetracycline and can even biodegrade tetracycline in the environment. In this study, we isolated a bacterium sp. XY-2, which could...
Few bacteria are resistant to tetracycline and can even biodegrade tetracycline in the environment. In this study, we isolated a bacterium sp. XY-2, which could biodegrade 74% tetracycline at pH 7.0 and 30°C within 6 days. Thereafter, we determined the whole genome sequence of sp. XY-2 genome is a single circular chromosome of 5.06 Mb in size. Genomic annotation showed that two AA6 family members-encoding genes and nine glutathione S-transferase (GSTs)-encoding genes could be relevant to tetracycline biodegradation. In addition, the average nucleotide identities (ANI) analysis between the genomes of sp. XY-2 and other spp. revealed that sp. XY-2 belongs to a new species. Moreover, comparative genome analysis of 36 strains identified the pan and specific genes, numerous single nucleotide polymorphisms (SNPs), insertions, and deletion variations (InDels) and different syntenial relationships in the genome of sp. XY-2. Finally, the evolution and the origin analysis of genes related to tetracycline resistance revealed that the six (48) genes and two specificgenes and in sp. XY-2 were acquired by horizontal gene transfer (HGT) events from sources related to , and some unidentified sources. As a new species, sp. XY-2 will be an excellent resource for the bioremediation of tetracycline-contaminated environment.
PubMed: 30761094
DOI: 10.3389/fmicb.2019.00033