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Scientific Reports Sep 2017Gentamicin, a broad spectrum antibiotic of the aminoglycoside class, is widely used for disease prevention of human beings as well as animals. Nowadays the environmental...
Gentamicin, a broad spectrum antibiotic of the aminoglycoside class, is widely used for disease prevention of human beings as well as animals. Nowadays the environmental issue caused by the disposal of wastes containing gentamicin attracts increasing attention. In this study, a gentamicin degrading bacterial consortia named AMQD4, including Providencia vermicola, Brevundimonas diminuta, Alcaligenes sp. and Acinetobacter, was isolated from biosolids produced during gentamicin production for the removal of gentamicin in the environment. The component and structure of gentamicin have a great influence on its degradation and gentamicin C1a and gentamicin C2a were more prone to being degraded. AMQD4 could maintain relatively high gentamicin removal efficiency under a wide range of pH, especially in an alkaline condition. In addition, AMQD4 could remove 56.8% and 47.7% of gentamicin in unsterilized and sterilized sewage in a lab-scale experiment, respectively. And among the isolates in AMQD4, Brevundimonas diminuta BZC3 performed the highest gentamicin degradation about 50%. It was speculated that aac3iia was the gentamicin degradation gene and the main degradation product was 3'-acetylgentamicin. Our results suggest that AMQD4 and Brevundimonas diminuta BZC3 could be important candidates to the list of superior microbes for bioremediation of antibiotic pollution.
Topics: Anti-Bacterial Agents; Bacteria; Biotransformation; Culture Media; Gentamicins; Hydrogen-Ion Concentration; Industrial Waste; Microbial Consortia; Sewage
PubMed: 28887556
DOI: 10.1038/s41598-017-11529-x -
Ultrasonics Sonochemistry Oct 2020Supercritical carbon dioxide (SC-CO) is a novel method for food pasteurization, but there is still room for improvement in terms of the process shortening and its use in...
Supercritical carbon dioxide (SC-CO) is a novel method for food pasteurization, but there is still room for improvement in terms of the process shortening and its use in products with high oil content. This study addressed the effect of high power ultrasound (HPU) on the intensification of the SC-CO inactivation of E. coli and B. diminuta in soybean oil-in-water emulsions. Inactivation kinetics were obtained at different pressures (100 and 350 bar), temperatures (35 and 50 °C) and oil contents (0, 10, 20 and 30%) and were satisfactorily described using the Weibull model. The experimental results showed that for SC-CO treatments, the higher the pressure or the temperature, the higher the level of inactivation. Ultrasound greatly intensified the inactivation capacity of SC-CO, shortening the process time by approximately 1 order of magnitude (from 50 to 90 min to 5-10 min depending on the microorganism and process conditions). Pressure and temperature also had a significant (p < 0.05) effect on SC-CO + HPU inactivation for both bacteria, although the effect was less intense than in the SC-CO treatments. E. coli was found to be more resistant than B. diminuta in SC-CO treatments, while no differences were found when HPU was applied. HPU decreased the protective effect of oil in the inactivation and similar microbial reductions were obtained regardless of the oil content in the emulsion. Therefore, HPU intensification of SC-CO treatments is a promising alternative to the thermal pasteurization of lipid emulsions with heat sensitive compounds.
PubMed: 32339868
DOI: 10.1016/j.ultsonch.2020.105138 -
Journal of Medical Case Reports Dec 2008Cystic fibrosis afflicted lungs support the growth of many bacteria rarely implicated in other cases of human infections.
INTRODUCTION
Cystic fibrosis afflicted lungs support the growth of many bacteria rarely implicated in other cases of human infections.
CASE PRESENTATION
We report the isolation and identification, by 16S rRNA amplification and sequencing, of two emerging pathogens resistant to colistin, Brevundimonas diminuta and Ochrobactrum anthropi, in a 17-year-old woman with cystic fibrosis and pneumonia. The patient eventually responded well to a 2-week regime of imipenem and tobramycin.
CONCLUSION
Our results clearly re-emphasize the emergence of new colistin-resistant pathogens in patients with cystic fibrosis.
PubMed: 19061488
DOI: 10.1186/1752-1947-2-373 -
Genome Announcements Jun 2015We report the draft genome of Brevundimonas diminuta strain XGC1, isolated from a tuberculosis-infected patient in Gujarat, India. This study also reveals that the...
We report the draft genome of Brevundimonas diminuta strain XGC1, isolated from a tuberculosis-infected patient in Gujarat, India. This study also reveals that the B. diminuta XGC1 strain has acquired mutation to confer resistance to quinolone drugs.
PubMed: 26112790
DOI: 10.1128/genomeA.00686-15 -
Applied and Environmental Microbiology Jun 2012The influence of mineral substrate composition and structure on bacterial calcium carbonate productivity and polymorph selection was studied. Bacterial calcium carbonate...
The influence of mineral substrate composition and structure on bacterial calcium carbonate productivity and polymorph selection was studied. Bacterial calcium carbonate precipitation occurred on calcitic (Iceland spar single crystals, marble, and porous limestone) and silicate (glass coverslips, porous sintered glass, and quartz sandstone) substrates following culturing in liquid medium (M-3P) inoculated with different types of bacteria (Myxococcus xanthus, Brevundimonas diminuta, and a carbonatogenic bacterial community isolated from porous calcarenite stone in a historical building) and direct application of sterile M-3P medium to limestone and sandstone with their own bacterial communities. Field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), powder X-ray diffraction (XRD), and 2-dimensional XRD (2D-XRD) analyses revealed that abundant highly oriented calcite crystals formed homoepitaxially on the calcitic substrates, irrespective of the bacterial type. Conversely, scattered spheroidal vaterite entombing bacterial cells formed on the silicate substrates. These results show that carbonate phase selection is not strain specific and that under equal culture conditions, the substrate type is the overruling factor for calcium carbonate polymorph selection. Furthermore, carbonate productivity is strongly dependent on the mineralogy of the substrate. Calcitic substrates offer a higher affinity for bacterial attachment than silicate substrates, thereby fostering bacterial growth and metabolic activity, resulting in higher production of calcium carbonate cement. Bacterial calcite grows coherently over the calcitic substrate and is therefore more chemically and mechanically stable than metastable vaterite, which formed incoherently on the silicate substrates. The implications of these results for technological applications of bacterial carbonatogenesis, including building stone conservation, are discussed.
Topics: Bacteria; Calcium; Calcium Carbonate; Construction Materials; Microscopy, Atomic Force; Microscopy, Electron, Scanning; Minerals; Myxococcus xanthus; Silicates; Substrate Specificity; X-Ray Diffraction
PubMed: 22447589
DOI: 10.1128/AEM.07044-11 -
Molecules (Basel, Switzerland) Mar 2020Enzyme-catalyzed hydrolysis of echothiophate, a P-S bonded organophosphorus (OP) model, was spectrofluorimetrically monitored, using Calbiochem Probe IV as the thiol...
Enzyme-catalyzed hydrolysis of echothiophate, a P-S bonded organophosphorus (OP) model, was spectrofluorimetrically monitored, using Calbiochem Probe IV as the thiol reagent. OP hydrolases were: the G117H mutant of human butyrylcholinesterase capable of hydrolyzing OPs, and a multiple mutant of phosphotriesterase, GG1, designed to hydrolyze a large spectrum of OPs at high rate, including V agents. Molecular modeling of interaction between Probe IV and OP hydrolases (G117H butyrylcholinesterase, GG1, wild types of and phosphotriesterases, and human paraoxonase-1) was performed. The high sensitivity of the method allowed steady-state kinetic analysis of echothiophate hydrolysis by highly purified G117H butyrylcholinesterase concentration as low as 0.85 nM. Hydrolysis was michaelian with = 0.20 ± 0.03 mM and = 5.4 ± 1.6 min. The GG1 phosphotriesterase hydrolyzed echothiophate with a high efficiency ( = 2.6 ± 0.2 mM; = 53400 min). With a = (2.6 ± 1.6) × 10 Mmin, GG1 fulfills the required condition of potential catalytic bioscavengers. quantum mechanics/molecular mechanics (QM/MM) and molecular docking indicate that Probe IV does not interact significantly with the selected phosphotriesterases. Moreover, results on G117H mutant show that Probe IV does not inhibit butyrylcholinesterase. Therefore, Probe IV can be recommended for monitoring hydrolysis of P-S bonded OPs by thiol-free OP hydrolases.
Topics: Biocatalysis; Butyrylcholinesterase; Caulobacteraceae; Echothiophate Iodide; Enzymes; Humans; Hydrolysis; Kinetics; Molecular Docking Simulation; Mutant Proteins; Organophosphorus Compounds; Phosphoric Triester Hydrolases; Spectrometry, Fluorescence; Sulfolobus
PubMed: 32192230
DOI: 10.3390/molecules25061371 -
Journal of Vascular Surgery Nov 2006Aortic aneurysms are common vascular conditions that cause considerable morbidity and mortality. Understanding of the mechanisms involved in the pathogenesis of the...
BACKGROUND
Aortic aneurysms are common vascular conditions that cause considerable morbidity and mortality. Understanding of the mechanisms involved in the pathogenesis of the condition remains limited. Recently, infection has been suggested as possible contributor in the development of the disease. The aim of the present study was to examine aortic aneurysms for the presence of bacterial DNA using polymerase chain reaction (PCR) targeting the 16S ribosomal RNA (rRNA) gene, followed by cloning and sequencing.
METHODS
Universal eubacterial primers were used to amplify 16S rRNA bacterial genes in 10 specimens from arterial walls of aortic aneurysms. Subsequently, PCR amplicons were cloned into Escherichia coli and sequencing of the cloned inserts was used to determine species identity or closest relatives by comparison with known sequences in GenBank.
RESULTS
Sequences of Stenotrophomonas spp., including S. maltophilia (formerly Pseudomonas homology group V) were detected in six aneurysm samples. Propionibacterium acnes was identified in five samples, and Brevundimonas diminuta (formerly P. diminuta) in four samples. Other species previously assigned to the Pseudomonas genus such as Comamonas testosteroni, Delftia acidovorans, Burkholderia cepacia, Herbaspirillum sp., and Acidovorax sp. were also detected. Some clones fell into other environmental species, including Methylobacterium sp. and Bradyrhizobium elkanii, and others represented bacteria that have not yet been cultivated. DNA sequences from oral bacteria, including Streptococcus sanguinis, Tannerella forsythia, and Leptotrichia buccalis were detected. Sequences from Prevotella melaninogenica and Lactobacillus delbrueckii, which are commonly found in both mouth and gastrointestinal tract, were also detected. Additional species included Dermacoccus spp. and Corynebacterium vitaeruminis.
CONCLUSIONS
A wide variety of bacteria, including oral bacteria, was found to colonize aortic aneurysms and may play a role in their development. Several of these microorganisms have not yet been cultivated.
CLINICAL RELEVANCE
Although Chlamydophila pneumoniae has been detected in aneurysmal walls, its exact role in the condition remains inconclusive. Overall, there is scarce information about the role of microorganisms in aneurysmal disease. In the present study, we used molecular genetics to detect a diversity of bacteria in arterial walls of aortic aneurysms. The presence of multiple microorganisms in aneurysmal disease may have implications for chemoprophylaxis and antibiotic treatment if directed only at C.pneumoniae.
Topics: Adult; Aged; Aneurysm, Infected; Aortic Aneurysm; Bacteria; Female; Genetic Variation; Humans; Male; Polymerase Chain Reaction; RNA, Bacterial; RNA, Ribosomal, 16S
PubMed: 17098542
DOI: 10.1016/j.jvs.2006.07.021 -
3 Biotech Dec 2016Endophytes are microorganisms which live symbiotically with almost all varieties of plant and in turn helping the plant in a number of ways. Instead of satisfactory...
Endophytes are microorganisms which live symbiotically with almost all varieties of plant and in turn helping the plant in a number of ways. Instead of satisfactory surface sterilization approaches, repeatedly occurring bacterial growth on in vitro rootstock cultures of peach and pear was identified and isolated as endophytic bacteria in our present study. Five different isolates from peach rootstocks were molecularly identified by 16S rRNA gene sequencing as Brevundimonas diminuta, Leifsonia shinshuensis, Sphingomonas parapaucimobilis Brevundimonas vesicularis, Agrobacterium tumefaciens while two endophytic isolates of pear were identified as Pseudoxanthomonas mexicana, and Stenotrophomonas rhizophilia. Identified endophytes were also screened for their potential of plant growth promotion according to indoleacetic acid (IAA) production, nitrogen fixation, solubilization of phosphate and production of siderophore. All seven endophytic isolates have shown positive results for IAA, nitrogen fixation and phosphate solubilization tests. However, two out of seven isolates showed positive results for siderophore production. On the basis of these growth promoting competences, isolated endophytes can be presumed to have significant influence on the growth of host plants. Future studies required to determine the antimicrobial susceptibility profile and potential application of these isolates in biological control, microbial biofertilizers and degradative enzyme production.
PubMed: 28330195
DOI: 10.1007/s13205-016-0442-6 -
European Journal of Hospital Pharmacy :... Dec 2023To investigate the container closure integrity of a closed system transfer device syringe adaptor lock in combination with disposable Luer-Lock syringes as the terminal...
OBJECTIVES
To investigate the container closure integrity of a closed system transfer device syringe adaptor lock in combination with disposable Luer-Lock syringes as the terminal closure device. The UK National Health Service (NHS) Pharmaceutical Quality Assurance Committee (PQAC) requires syringe integrity data for final storage devices of aseptic products such as chemotherapy drugs when prepared in advance and stored before use, as is standard practice for dose banded drugs. The assessment comprised both physical and microbial integrity testing of the combination closed system/Luer-Lock syringe containers at syringe sizes of 1 mL, 20 mL, and 50 mL.
METHODS
Integrity testing was performed as described in the NHS Pharmaceutical Quality Assurance Committee yellow cover document, second edition 2013 'Protocols for the Integrity Testing of Syringes', with Chemfort (Simplivia, IL) syringe adaptor lock (SAL) devices as replacement for sterile blind hubs. Microbiological integrity was assessed according to method 1 part 1.4 using at 32°C for up to 14 days of contact time. Two positive control devices per syringe size were tested using a blind hub cap as closure which was loosened before the test. Physical integrity was assessed using method 3 of the yellow cover document which is a dye intrusion method. Dye intrusion was assessed both visually and using a validated ultraviolet-visible spectrophotometer method. For each size/batch of test articles a positive control device (n=1) was assessed using a wire wrapped around the syringe plunger tip deliberately compromising integrity. Negative controls for each size (n=1) consisted of devices not immersed in methylene blue dye.
RESULTS
Chemfort syringe adaptor lock/Luer-Lock syringe combinations were shown to be: (1) free of microbiological contamination after 14 days of contact time (n=60); and (2) free of dye intrusion at all syringe sizes tested (n=61 in total). The data demonstrate 100% closure integrity of the final container system when the Chemfort syringe adaptor lock replaces the syringe hub as the terminal closure device. All positive control devices demonstrated system suitability as container integrity was compromised in all positive control tests. All negative controls were negative for microbial and dye intrusion.
CONCLUSIONS
Syringe adaptor lock components complied with the NHS Pharmaceutical Quality Assurance Committee yellow cover document syringe integrity requirements when used as the terminal closure of Luer-Lock disposable syringes from 1 mL up to 50 mL. Therefore, syringe adaptor lock (Chemfort) can be used as the terminal closure system for pre-filled syringes of chemotherapeutic drug products prepared in advance in UK NHS pharmacy technical services.
Topics: Drug Contamination; Drug Packaging; Pharmaceutical Preparations; State Medicine; Syringes
PubMed: 35410874
DOI: 10.1136/ejhpharm-2021-003148 -
Applied and Environmental Microbiology Feb 2001We analyzed the composition of aggregate (lake snow)-associated bacterial communities in Lake Constance from 1994 until 1996 between a depth of 25 m and the sediment...
We analyzed the composition of aggregate (lake snow)-associated bacterial communities in Lake Constance from 1994 until 1996 between a depth of 25 m and the sediment surface at 110 m by fluorescent in situ hybridization with rRNA-targeted oligonucleotide probes of various specificity. In addition, we experimentally examined the turnover of dissolved amino acids and carbohydrates together with the microbial colonization of aggregates formed in rolling tanks in the lab. Generally, between 40 and more than 80% of the microbes enumerated by DAPI staining (4',6'-diamidino-2-phenylindole) were detected as Bacteria by the probe EUB338. At a depth of 25 m, 10.5% +/- 7.9% and 14.2% +/- 10.2% of the DAPI cell counts were detected by probes specific for alpha- and beta-Proteobacteria. These proportions increased to 12.0% +/- 3.3% and 54.0% +/- 5.9% at a depth of 50 m but decreased again at the sediment surface at 110 m to 2.7% +/- 1.4% and 41.1% +/- 8.4%, indicating a clear dominance of beta-Proteobacteria at depths of 50 and 110 m, where aggregates have an age of 3 to 5 and 8 to 11 days, respectively. From 50 m to the sediment surface, cells detected by a Cytophaga/Flavobacteria-specific probe (CF319a) comprised increasing proportions up to 18% of the DAPI cell counts. gamma-Proteobacteria always comprised minor proportions of the aggregate-associated bacterial community. Using only two probes highly specific for clusters of bacteria closely related to Sphingomonas species and Brevundimonas diminuta, we identified between 16 and 60% of the alpha-Proteobacteria. In addition, with three probes highly specific for close relatives of the beta-Proteobacteria Duganella zoogloeoides (formerly Zoogloea ramigera), Acidovorax facilis, and Hydrogenophaga palleroni, bacteria common in activated sludge, 42 to 70% of the beta-Proteobacteria were identified. In the early phase (<20 h) of 11 of the 15 experimental incubations of aggregates, dissolved amino acids were consumed by the aggregate-associated bacteria from the surrounding water. This stage was followed by a period of 1 to 3 days during which dissolved amino acids were released into the surrounding water, paralleled by an increasing dominance of beta-Proteobacteria. Hence, our results show that lake snow aggregates are inhabited by a community dominated by a limited number of alpha- and beta-Proteobacteria, which undergo a distinct succession. They successively decompose the amino acids bound in the aggregates and release substantial amounts into the surrounding water during aging and sinking.
Topics: Alphaproteobacteria; Amino Acids; Betaproteobacteria; Carbohydrate Metabolism; Ecosystem; Fresh Water; Geologic Sediments
PubMed: 11157226
DOI: 10.1128/AEM.67.2.632-645.2001