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Indian Journal of Pathology &... 2017Brevundimonas has rarely been isolated from clinical specimens. We here report a case of Brevundimonas diminuta infection in an 18-year-old male patient with nephrotic...
Brevundimonas has rarely been isolated from clinical specimens. We here report a case of Brevundimonas diminuta infection in an 18-year-old male patient with nephrotic syndrome. B. diminuta was identified by the VITEK 2 Compact system, following isolation from his blood sample. To the best of our knowledge, B. diminuta has not been reported in patients with nephrotic syndrome.
Topics: Adolescent; Bacteriological Techniques; Blood; Caulobacteraceae; Gram-Negative Bacterial Infections; Humans; Male; Nephrotic Syndrome
PubMed: 28631656
DOI: 10.4103/IJPM.IJPM_679_15 -
The Journal of Antimicrobial... Jun 2005To report infections caused by Brevundimonas diminuta and antibiotic studies of this Gram-negative bacterium.
OBJECTIVES
To report infections caused by Brevundimonas diminuta and antibiotic studies of this Gram-negative bacterium.
PATIENTS AND METHODS
Seven patients with infection and eight bacterial strains were studied. Tests included antibiotic susceptibility and analysis of the DNA gyrase and topoisomerase genes and the effect of efflux pump inhibitor Phe-Arg-beta-naphthylamide (PANA).
RESULTS
The patients all had underlying disease of cancer. The infections involved bloodstream (one case), intravascular catheter (four cases), urinary tract (one case) and pleural space (one case of empyema). Fever up to 39.2 degrees C characterized these infections, which resolved upon treatment by combination antibiotics. Microbiologically, all organisms were resistant to multiple fluoroquinolones and cefepime, but were susceptible to amikacin, imipenem and ticarcillin/clavulanate. These quinolone-resistant B. diminuta strains were probably selected out by the prophylactic use of a quinolone in six of these patients. Additionally, the B. diminuta type strain ATCC 11568(T) that was isolated before the quinolone era from water was also resistant to ciprofloxacin and intermediate to levofloxacin, suggesting intrinsic quinolone resistance. The DNA gyrase and topoisomerase of six analysed strains all contained GyrA Ala-83 and Met-87, GyrB Leu-466 or Thr-466, and ParC Gln-57, Val-66 and Ala-80 that were probably the cause of fluoroquinolone resistance. PANA had nearly negligible effect.
CONCLUSIONS
B. diminuta is intrinsically resistant to fluoroquinolones and can be selected out to cause infections.
Topics: Adult; Aged; Base Sequence; DNA Gyrase; DNA Topoisomerase IV; Dipeptides; Drug Resistance, Bacterial; Female; Fluoroquinolones; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Molecular Sequence Data; Pseudomonas; Pseudomonas Infections
PubMed: 15883180
DOI: 10.1093/jac/dki139 -
Indian Journal of Pathology &... 2015Brevundimonas diminuta are ubiquitous in the environment, but are infrequently isolated from clinical samples. Here we report a case of B. diminuta bacteremia in a man...
Brevundimonas diminuta are ubiquitous in the environment, but are infrequently isolated from clinical samples. Here we report a case of B. diminuta bacteremia in a man with myelodysplastic syndromes (MDS) at a teaching hospital in China and review the previously reported cases. The organism was confirmed by culture and 16s rRNA sequence analysis with highly sensitivity to broad-spectrum antibiotics. Our report and other cases demonstrated that the optimal therapeutic duration for B. diminuta infections in various situations remains to be established.
Topics: Anti-Bacterial Agents; Bacteremia; Caulobacteraceae; China; DNA, Bacterial; DNA, Ribosomal; Gram-Negative Bacterial Infections; Hospitals, Teaching; Humans; Male; Microbial Sensitivity Tests; Middle Aged; RNA, Ribosomal, 16S; Sequence Analysis, DNA
PubMed: 26275273
DOI: 10.4103/0377-4929.162920 -
Infection Control and Hospital... May 2017We report an epidemiological investigation of a cluster of Brevundimonas diminuta isolates cultured from sterile sites. Inoculation of supplement medium yielded growth...
We report an epidemiological investigation of a cluster of Brevundimonas diminuta isolates cultured from sterile sites. Inoculation of supplement medium yielded growth of B. diminuta. Molecular typing indicated likely contamination of the lot. No B. diminuta was further isolated after replacement of the supplement with a new lot number. Infect Control Hosp Epidemiol 2017;38:598-601.
Topics: Adult; Aged; Alabama; Caulobacteraceae; Cross Infection; Culture Media; Databases, Factual; Disease Outbreaks; Drug Contamination; Female; Gram-Negative Bacterial Infections; Hospitals, University; Humans; Male; Middle Aged; Polymerase Chain Reaction; Young Adult
PubMed: 28264729
DOI: 10.1017/ice.2017.17 -
Ecotoxicology and Environmental Safety Mar 2016Arsenic (As), a toxic metalloid adversely affects plant growth in polluted areas. In the present study, we investigated the possibility of improving phytostablization of...
Arsenic (As), a toxic metalloid adversely affects plant growth in polluted areas. In the present study, we investigated the possibility of improving phytostablization of arsenic through application of new isolated strain Brevundimonas diminuta (NBRI012) in rice plant [Oryza sativa (L.) Var. Sarju 52] at two different concentrations [10ppm (low toxic) and 50ppm (high toxic)] of As. The plant growth promoting traits of bacterial strains revealed the inherent ability of siderophores, phosphate solubilisation, indole acetic acid (IAA), 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase production which may be associated with increased biomass, chlorophyll and MDA content of rice and thereby promoting plant growth. The study also revealed the As accumulation property of NBRI012 strain which could play an important role in As removal from contaminated soil. Furthermore, NBRI012 inoculation significantly restored the hampered root epidermal and cortical cell growth of rice plant and root hair elimination. Altogether our study highlights the multifarious role of B. diminuta in mediating stress tolerance and modulating translocation of As in edible part of rice plant.
Topics: Amino Acids, Cyclic; Arsenic; Biodegradation, Environmental; Chlorophyll; Gram-Negative Bacteria; Oryza; Plant Roots; Soil Pollutants
PubMed: 26650422
DOI: 10.1016/j.ecoenv.2015.11.020 -
International Journal of Biological... Apr 2023The microflora in the activated sludge of propylene oxide saponification wastewater is characterized by a clear succession after enrichment and domestication, and the...
The microflora in the activated sludge of propylene oxide saponification wastewater is characterized by a clear succession after enrichment and domestication, and the specifically enriched strains can significantly increase the yield of polyhydroxyalkanoate. In this study, Pseudomonas balearica R90 and Brevundimonas diminuta R79, which are dominant strain after domestication, were selected as models to examine the interactive mechanisms associated with the synthesis of polyhydroxyalkanoate by co-cultured strains. RNA-Seq analysis revealed the up-regulated expression of the acs and phaA genes of strains R79 and R90 in the co-culture group, which enhanced their utilization of acetic acid and synthesis of poly-β-hydroxybutyrate. Cell dry weight and the yield of poly-β-hydroxybutyrate in the co-culture group were accordingly considerably higher than those in the respective pure culture groups. In addition, two-component system, quorum-sensing, flagellar synthesis-related, and chemotaxis-related genes were enriched in strain R90, thereby indicating that compared with the R79 strain, R90 can adapt more rapidly to a domesticated environment. Expression of the acs gene was higher in R79 than in R90, and consequently, strain R79 could more efficiently assimilate acetate in the domesticated environment, and thus predominated in the culture population at the end of the fermentation period.
Topics: Polyhydroxyalkanoates; Pseudomonas; Polyesters; Hydroxybutyrates
PubMed: 36796552
DOI: 10.1016/j.ijbiomac.2023.123667 -
International Journal of Systematic... Jul 1994The taxonomic positions of strains previously assigned to Pseudomonas diminuta and Pseudomonas vesicularis were investigated by a polyphasic approach. The results of... (Comparative Study)
Comparative Study
Classification of Pseudomonas diminuta Leifson and Hugh 1954 and Pseudomonas vesicularis Büsing, Döll, and Freytag 1953 in Brevundimonas gen. nov. as Brevundimonas diminuta comb. nov. and Brevundimonas vesicularis comb. nov., respectively.
The taxonomic positions of strains previously assigned to Pseudomonas diminuta and Pseudomonas vesicularis were investigated by a polyphasic approach. The results of DNA-rRNA hybridization studies indicated that these two species belong to a separate genus in the alpha subclass (rRNA superfamily IV) of the Proteobacteria, for which the name Brevundimonas is proposed. Genus delineation and species delineation were determined by comparing the results of numerical analyses of whole-cell protein patterns, fatty acid compositions, and phenotypic characteristics and by measuring DNA base ratios and degrees of DNA relatedness. Taxonomic characteristics of Brevundimonas diminuta and Brevundimonas vesicularis strains were compared with characteristics of reference strains belonging to the following phylogenetically related taxa: a group of organisms gathered in Enevold Falsen group 21, the genera Sphingomonas and Rhizomonas, and the generically misclassified organisms [Pseudomonas] echinoides and "[Pseudomonas] riboflavina."
Topics: Animals; Bacterial Proteins; Base Composition; DNA, Bacterial; Electrophoresis, Polyacrylamide Gel; Fatty Acids; Gram-Negative Aerobic Bacteria; Humans; Nucleic Acid Hybridization; Phenotype; Polyamines; Pseudomonas; Terminology as Topic
PubMed: 8068543
DOI: 10.1099/00207713-44-3-499 -
Journal of Aerosol Science Dec 2017This study experimentally assessed bacterial water-to-air partitioning coefficients resulting from showerhead aerosolization of water contaminated with or , and...
This study experimentally assessed bacterial water-to-air partitioning coefficients resulting from showerhead aerosolization of water contaminated with or , and estimated human exposure through inhalation. Dechlorinated tap water was spiked with two cell densities (10 and 10 CFU l) and cycled at three temperatures (10, 25, and 37 or 40ºC) through a full-scale shower system. For reproducibility, spiked water concentrations were intentionally higher than found in natural environments. Three types of samplers measured size distribution and viable concentrations throughout the system. Results indicate low levels of respirable bioaerosols were generated. The ratio of bacterial contaminant that was effectively aerosolized (bacterial water-to-air partitioning coefficient, ) was low - averaging 1.13×10 L m for and 8.31×10 L m for . However, the respirable fraction of aerosolized organisms was high, averaging above 94% (in shower) and above 99% (downstream) for both organisms. This study found no significant difference in bioaerosol load for a forward facing versus reverse facing individual. Further, for the average hot shower (33-43°C) the total number of respirable bioaerosols is higher, but the observed culturability of those aerosolized cells is lower when compared to lower temperatures. Bacterial water to air partitioning coefficients were calculated to predict microbial air concentration and these empirical parameters may be used for assessing inhalation as a route of exposure to pathogens in contaminated waters.
PubMed: 30319141
DOI: 10.1016/j.jaerosci.2017.08.008 -
Journal of Industrial Microbiology &... Apr 2010Brevundimonas diminuta is used as a control organism for validating the efficiency of water filtration systems. Since these protocols use nonselective growth media,...
Brevundimonas diminuta is used as a control organism for validating the efficiency of water filtration systems. Since these protocols use nonselective growth media, heterotrophic plate count bacteria (HPCs) indigenous to the water distribution system may interfere with B. diminuta enumeration, thus leading to inaccurate assessment of the filter's microbial reduction capability. This could negatively impact public health as unsafe drinking water may be produced. This study was conducted to evaluate different potential routes for selective enumeration of B. diminuta in drinking water. B. diminuta's biochemical and molecular relationships to HPCs recovered from a laboratory drinking-water system were investigated. Of the 24 HPC morphotypes recovered, members of the Alpha- and Betaproteobacteria were most commonly identified. Based on comparisons of catabolic profiles (generated by the Biolog system) using principal component analysis, B. diminuta possessed similar metabolic patterns to several of the Alphaproteobacteria (Sphingomonas and Caulobacter), indicating that development of a selective medium based solely on carbon source was not feasible. Antibiotic susceptibility profiles revealed that the HPCs were least resistant to kanamycin, making it a candidate for future selective applications. Sequence comparisons of partial 16S rRNA sequences did not reveal any distinct similarities. However, basic local alignment search tool (BLAST) alignments of the gyrB and rpoD sequences for B. diminuta did show uniqueness, with the next closest match being to Caulobacter (88% and 79% similarity, respectively). Future investigation will focus on applying molecular assays, such as fluorescent in situ hybridization and quantitative real-time polymerase chain reaction (PCR), and incorporating an antibiotic marker or expressed fluorescent protein into the wild-type strain of B. diminuta for selective enumeration of B. diminuta.
Topics: Bacterial Typing Techniques; Caulobacteraceae; Cluster Analysis; Colony Count, Microbial; Culture Media; DNA Gyrase; DNA, Bacterial; DNA, Ribosomal; DNA-Directed RNA Polymerases; Microbial Sensitivity Tests; Molecular Sequence Data; Phylogeny; RNA, Ribosomal, 16S; Sensitivity and Specificity; Sequence Analysis, DNA; Sigma Factor; Water Microbiology; Water Purification
PubMed: 20087629
DOI: 10.1007/s10295-010-0689-6 -
Food Research International (Ottawa,... Jul 2024Ochratoxin A (OTA) is a notorious mycotoxin commonly contaminating food products worldwide. In this study, an OTA-degrading strain Brevundimonas diminuta HAU429 was...
Ochratoxin A (OTA) is a notorious mycotoxin commonly contaminating food products worldwide. In this study, an OTA-degrading strain Brevundimonas diminuta HAU429 was isolated by using hippuryl-L-phenylalanine as the sole carbon source. The biodegradation of OTA by strain HAU429 was a synergistic effect of intracellular and extracellular enzymes, which transformed OTA into ochratoxin α (OTα) through peptide bond cleavage. Cytotoxicity tests and cell metabolomics confirmed that the transformation of OTA into OTα resulted in the detoxification of its hepatotoxicity since OTA but not OTα disturbed redox homeostasis and induced oxidative damage to hepatocytes. Genome mining identified nine OTA hydrolase candidates in strain HAU429. They were heterologously expressed in Escherichia coli, and three novel amidohydrolase BT6, BT7 and BT9 were found to display OTA-hydrolyzing activity. BT6, BT7 and BT9 showed less than 45 % sequence identity with previously identified OTA-degrading amidohydrolases. BT6 and BT7 shared 60.9 % amino acid sequence identity, and exhibited much higher activity towards OTA than BT9. BT6 and BT7 could completely degrade 1 μg mL of OTA within 1 h and 50 min, while BT9 hydrolyzed 100 % of OTA in the reaction mixture by 12 h. BT6 was the most thermostable retaining 38 % of activity after incubation at 70 °C for 10 min, while BT7 displayed the highest tolerance to ethanal remaining 76 % of activity in the presence of 6 % ethanol. This study could provide new insights towards microbial OTA degradation and promote the development of enzyme-catalyzed OTA detoxification during food processing.
Topics: Ochratoxins; Caulobacteraceae; Biodegradation, Environmental; Amidohydrolases; Food Contamination
PubMed: 38763660
DOI: 10.1016/j.foodres.2024.114409