Project description:We previously identified and presented the draft genome of a Xanthomonadaceae bacterial strain Dyella japonica A8 which shows quorum-quenching activity. Here, we report the complete, closed genome sequence of this bacterium. This complete genome may help to further investigate the comparative quorum-quenching activity among D. japonica strains.
Project description:A blood culture from a 65-year-old febrile man undergoing hemodialysis revealed, 5 days after inoculation, an unusual gram-negative fusiform rod with darting motility. During another episode of fever 21 days later, this Campylobacter-like organism was again recovered from three blood cultures and subcultured under an H2-enriched microaerobic atmosphere. The organism was catalase negative and oxidase positive and hydrolyzed urea rapidly. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of whole-cell proteins was indistinguishable from that of "Flexispira rappini" LMG 8738 described by Archer et al. in 1988 (J. R. Archer, S. Romero, A. E. Ritchier, M. E. Hamacher, B. M. Steiner, J. H. Bryner, and R. F. Schell, J. Clin. Microbiol. 26:101-105, 1988). The analysis of the 16S ribosomal DNA sequence revealed a similarity of 99.3% between the two strains. The patient recovered completely after a 4-week course of meropenem therapy. This is the first reported case of a recurrent "F. rappini" bacteremia in an adult patient, which confirms that this organism may be an invasive pathogen in immunocompromised patients, like other newly described Helicobacter species.
Project description:Paenibacilli are gram-positive, aerobic bacteria that are related to Bacilli but differ in the DNA encoding their 16S rRNA. Until recently, these organisms were not known to cause human disease. There are now several reports of human infection caused by a few members of this genus, most commonly by P. alvei. We report a human infection in a patient with a permacath for chronic hemodialysis who was found to have bacteremia caused by P. thiaminolyticus, which is an environmental bacterium that has never been found to cause human disease. We identified this bacterium by biochemical tests, cloning, sequencing the genomic DNA encoding its 16S rRNA, growth characteristics, and electron microscopic studies. This constitutes the first report of a human infection caused by this organism.
Project description:Hemodialysis catheter-related bacteremia is a common clinical problem with several management options. We performed a systematic review and meta-analysis to determine cure proportions with systemic antibiotics, antibiotic lock solution, and guidewire exchange. We searched databases and registries; conference proceedings from relevant medical societies; and article reference lists. Data regarding management approach, cure, follow-up, recurrence, complications, and microbiology were abstracted and pooled from 28 selected publications. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated from a mixed effects logistic regression model. In total, 1596 patients with tunneled hemodialysis catheter-related bacteremia were divided into groups on the basis of treatment with systemic antibiotics (n=697), antibiotic lock solution (n=546), or guidewire exchange (n=353). Antibiotic lock solution and guidewire exchange had similar cure proportions that were superior to systemic antibiotics alone (OR, 2.08; 95% CI, 1.25 to 3.45; P<0.01 for antibiotic lock solution; OR, 2.88; 95% CI, 1.82 to 4.55; P<0.001 for guidewire exchange versus systemic antibiotics). Cure proportions were highest for coagulase-negative staphylococci followed by gram-negative rods and Staphylococcus aureus. Among S. aureus infections, guidewire exchange led to a higher cure proportion than systemic antibiotics or antibiotic lock solution (OR, 3.33; 95% CI, 1.17 to 9.46; P=0.02; OR, 4.72; 95% CI, 1.79 to 12.46; P=0.002, respectively). Thus, results of this study suggest that tunneled hemodialysis catheter-related bacteremia should be treated with either guidewire exchange or antibiotic lock solution. Future studies should address prospectively whether one strategy is better than the other overall and for specific pathogens.
Project description:Mycobacterium obuense is a pigmented, rapidly growing mycobacterium. Because it has been considered nonpathogenic, M. obuense is being investigated in clinical trials of cancer immunotherapy and bioremediation. We report a case of bacteremia caused by M. obuense in a patient with pneumonia, showing its potential pathogenicity.
Project description:We describe the first case of community-acquired bacteremia caused by Acinetobacter radioresistens; the patient was a 32-year-old HIV-positive neutropenic woman. Ambiguous Gram staining and poor biochemical reactivity of blood culture isolates misguided early diagnosis and therapy. Bacterial identification was based on 16S rDNA sequence analysis. A. radioresistens can be considered as a cause of opportunistic infection in immunodeficient patients.