RESUMEN
Mid-infrared laser spectroscopy was used to investigate common bacteria encountered in biopharmaceutical industries. The study involved the detection of bacteria using quantum cascade laser spectroscopy coupled to a grazing angle probe (QCL-GAP). Substrates similar to surfaces commonly used in biopharmaceutical industries were used as support media for the samples. Reflectance measurements were assisted by Multivariate Analysis (MVA) to assemble a powerful spectroscopic technique with classification and identification resources. The species analyzed, Staphylococcus aureus, Staphylococcus epidermidis, and Micrococcus luteus, were used to challenge the technique's capability to discriminate from microorganisms of the same family. Principal Components Analysis and Partial Least Squares-Discriminant Analysis differentiated between the bacterial species, using QCL-GAP-MVA as the reference. Spectral differences in the bacterial membrane were used to determine if these microorganisms were present in the samples analyzed. Results herein provided effective discrimination for the bacteria under study with high sensitivity and specificity.
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Rayos Láser , Análisis Multivariante , Análisis de Componente Principal , Staphylococcus epidermidis/aislamiento & purificación , Staphylococcus aureus/aislamiento & purificación , Micrococcus luteus/aislamiento & purificación , Microbiología Industrial , Análisis Espectral , Análisis DiscriminanteAsunto(s)
Endocarditis Bacteriana/complicaciones , Micrococcus luteus/patogenicidad , Infarto Pulmonar/diagnóstico por imagen , Infarto Pulmonar/microbiología , Antibacterianos/uso terapéutico , Niño , Endocarditis Bacteriana/diagnóstico , Endocarditis Bacteriana/tratamiento farmacológico , Femenino , Humanos , Micrococcus luteus/aislamiento & purificación , Infarto Pulmonar/tratamiento farmacológico , Infarto Pulmonar/etiología , Tomografía Computarizada por Rayos XRESUMEN
In this study, Li+ biosorption profiles of Micrococcus luteus and Bacillus pumilus bacterial strains were investigated. Comparative surface characterization of the biomasses revealed that B. pumilus had a significantly greater surface negativity than the other, which had a direct positive effect on the ability to attract the Li+ ions. Biosorption experiments showed that B. pumilus cell had more efficient performance at all pH and initial Li+ concentration values in the ranges of 3.0-10.0 and 2.5-20.0 mg/L, respectively. The maximum adsorption capacities obtained at initial Li+ concentration of 20.0 mg/L and pH 9.0 were 1.160 mg Li+/g (167.1 µmol/g) and 2.280 mg Li+/g (328.5 µmol/g) for M. luteus and B. pumilus, respectively. For all the cases studied, the biosorption equilibrium was reached very quickly, suggesting that physical interaction dominated this process. Experimental data were found to be compatible with both Langmuir and Freundlich models under the studied experimental conditions. This study highlights the idea that B. pumilus bacterial strain will be a new and preferred biosorbent for Li+ ions by providing a low cost, rapid and quite efficient process.
Asunto(s)
Bacillus pumilus , Litio/metabolismo , Micrococcus luteus , Bacillus pumilus/crecimiento & desarrollo , Bacillus pumilus/aislamiento & purificación , Micrococcus luteus/crecimiento & desarrollo , Micrococcus luteus/aislamiento & purificaciónRESUMEN
BACKGROUND: Surgical site infections are a global patient safety concern. Due to lack of evidence on contamination, pre-set surgical goods are sometimes disposed of or re-sterilized, thus increasing costs, resource use, and environmental effects. AIM: To investigate time-dependent bacterial air contamination of covered and uncovered sterile goods in the operating room. METHODS: Blood agar plates (N = 1584) were used to detect bacterial air contamination of sterile fields on 48 occasions. Each time, three aerobe and three anaerobe plates were used as baseline to model the preparation time, and 60 (30 aerobe, 30 anaerobe) were used to model the time pending before operation; half of these were covered with sterile drapes and half remained uncovered. Plates were collected after 4, 8, 12, 16, and 24 h. FINDINGS: Mean time before contamination was 2.8 h (95% confidence interval: 2.1-3.4) in the uncovered group and 3.8 h (3.2-4.4) in the covered group (P = 0.005). The uncovered group had 98 colony-forming units (cfu) versus 20 in the covered group (P = 0.0001). Sixteen different micro-organisms were isolated, the most common being Cutibacterium acnes followed by Micrococcus luteus. Of 32 Staphylococcus cfu, 14 were antibiotic resistant, including one multidrug-resistant Staphylococcus epidermidis. CONCLUSION: Protecting sterile fields from bacterial air contamination with sterile covers enhances the durability of sterile goods up to 24 h. Prolonged durability of sterile goods might benefit patient safety, since surgical sterile material could be prepared in advance for acute surgery, thereby enhancing quality of care and reducing both climate impact and costs.
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Microbiología del Aire , Contaminación de Equipos , Quirófanos , Humanos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Micrococcus luteus/aislamiento & purificación , Propionibacteriaceae/aislamiento & purificación , Staphylococcus epidermidis , Infección de la Herida Quirúrgica/prevención & control , Factores de TiempoRESUMEN
The colour purity and versatility of fabrication of one-dimensional photonic crystals (1D PhCs) make them ideal candidates for colorimetric sensing of a variety of analytes. For instance, the detection of bacterial contaminants in food via colorimetric sensors can be highly appealing, as most of the existing detection techniques are in general time-consuming and the read-out requires specialised personnel. Here, we present a colorimetric sensor based on hybrid plasmonic/photonic 1D crystals. We demonstrate that the modification of the silver plasmon resonance brought about by the effective silver/bacterium interaction can be translated into the visible spectral region, producing a change in the structural colour. In addition, we observe a superior colorimetric sensitivity against the Gram negative Escherichia coli compared to the Gram positive Micrococcus luteus, a result that we attribute to the more efficient electrostatic interaction and cellular adhesion between the silver surface and the Gram-negative bacteria outer membrane. This approach demonstrates that in principle an easy colorimetric detection of bacterial contaminants can be achieved through the use of bio-responsive plasmonic materials, such as silver, whose selective electrostatic interaction with bacterial cell wall is well-known and occurs without the need of chemical functionalisation.
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Colorimetría/métodos , Escherichia coli/aislamiento & purificación , Micrococcus luteus/aislamiento & purificación , Plata/química , Cristalización , Microscopía Electrónica de Rastreo , FotonesRESUMEN
Multiple heavy metal-resistant bacterium, Micrococcus luteus strain AS2, was isolated from industrial waste water of District Sheikhupura, Pakistan. The isolated bacterium showed minimum inhibitory concentrations of 55 and 275 mM against arsenite and arsenate. The bacterial strain also showed resistance against other heavy metal ions, i.e., lead, cadmium, chromium, mercury, nickel, and zinc, apart from arsenic. The optimum temperature and pH were 37 °C and 7, respectively. The antioxidant enzymes such as catalase were significantly increased under arsenite stress. The increase in 43.9% of GSH/GSSG and 72.72% of non-protein thiol was determined under15 mM arsenite stress. Bacterial genome was sequenced through Illumina and Nanopore and genes related to arsenic and other heavy metals were identified and blast (tblastx) on NCBI. Through scanning electron microscopy, no morphological changes were observed in bacterial cells under arsenite stress. The peaks appeared in EDX showed that there is surface adsorption of arsenite in bacterial cell while it was confirmed from Fourier transformed infrared spectroscopy analysis that there is some interaction between arsenite and functional groups present on the surface of bacterial cell. The SDS-PAGE analysis of whole-cell proteins under 15 mM arsenite stress clearly revealed that there is upregulation of some proteins in ranged of 60 to 34 kDa. The bioremediation efficiency (E) of bacterial biomass was 72% after 2 h and 99% after 10 h. The bioremediation efficiency of bacterial biomass is an indicator for the isolated bacterium to employ as a potential candidate for the amelioration of sites contaminated with arsenic.
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Arsénico/metabolismo , Micrococcus luteus/aislamiento & purificación , Micrococcus luteus/metabolismo , Aguas Residuales/microbiología , Biodegradación Ambiental , Cadmio/metabolismo , Cromo/metabolismo , Residuos Industriales/análisis , Micrococcus luteus/genéticaRESUMEN
In this study, the coupling of magnetic enrichment of bacteria from real samples with rapid surface enhanced Raman spectroscopy (SERS) detection was reported. The selective isolation and enrichment for the model bacteria Escherichia coli (E. coli) was performed using E. coli (primary) antibody bound-magnetic gold (Fe3O4@Au) nanoparticles. Following isolation and enrichment, the rennet enzyme was used to cleave of casein modified Fe3O4/Au-PEI nanoparticles from primary antibody-bound bacteria to prevent the nanoparticle aggregation and provide the movement of bacteria on nitrocellulose membrane. In the first part of the study, optimization studies were carried out namely; the amounts of gold nanoparticles (AuNPs), polyethyleneimine coated magnetic gold (Fe3O4/Au-PEI) nanoparticles, casein and rennet enzyme. The SERS signals of DTNB (5,5'-Dithiobis(2-nitrobenzoic acid)) molecule were collected on the test line and a calibration curve was plotted by using signal intensities. The correlation between the concentration of E. coli and SERS signal was found to be linear within the range of 101-107â¯cfu/mL (R2â¯=â¯0.984, LODâ¯=â¯0.52â¯cfu/mL and LOQâ¯=â¯1.57â¯cfu/mL). The selectivity of the paper-based lateral flow immunoassay (LFIA) was examined with Bacillus subtilis (B. subtilis), Micrococcus luteus (M. luteus), Salmonella enteritidis (S. enteritidis) which did not produce any significant response compared with E. coli measurement. Finally, the developed paper-based LFIA was tested with urine and milk samples. The obtained SERS results were compared with a plate counting method results which were in a good accordance. The developed method was found as rapid and sensitive to E. coli with a total analysis time of less than 60â¯min.
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Bacterias/aislamiento & purificación , Técnicas de Tipificación Bacteriana/métodos , Nanopartículas de Magnetita/química , Leche/microbiología , Papel , Orina/microbiología , Animales , Anticuerpos/inmunología , Bacillus subtilis/aislamiento & purificación , Caseínas/inmunología , Quimosina/química , Escherichia coli/aislamiento & purificación , Oro/química , Límite de Detección , Micrococcus luteus/aislamiento & purificación , Salmonella enteritidis/aislamiento & purificaciónAsunto(s)
Bacteriemia/microbiología , Infecciones por Bacterias Grampositivas/microbiología , Huésped Inmunocomprometido , Micrococcus luteus/patogenicidad , Antibacterianos/uso terapéutico , Bacteriemia/tratamiento farmacológico , Bacteriemia/inmunología , Catéteres Venosos Centrales/efectos adversos , Catéteres Venosos Centrales/microbiología , Epoprostenol/uso terapéutico , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Infecciones por Bacterias Grampositivas/inmunología , Humanos , Masculino , Micrococcus luteus/aislamiento & purificación , Persona de Mediana EdadRESUMEN
Central nervous system infections, which are rarely seen in systemic lupus erythematosus (SLE), have considerably high mortality but they are difficult to distinguish from neuropsychiatric manifestation of lupus. This article reports the case of a patient with SLE with brain abscess which developed during immunosuppressive therapy for lupus nephritis. The patient completely recovered without neurological sequelae by open surgical drainage and 12-week antibiotic therapy. It is recommended that CNS infections must be excluded in patients with SLE, particularly who are receiving immunosuppressive therapy.
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Absceso Encefálico/microbiología , Infecciones Bacterianas del Sistema Nervioso Central/microbiología , Infecciones por Bacterias Grampositivas/microbiología , Huésped Inmunocomprometido , Inmunosupresores/efectos adversos , Lupus Eritematoso Sistémico/tratamiento farmacológico , Nefritis Lúpica/tratamiento farmacológico , Micrococcus luteus/aislamiento & purificación , Infecciones Oportunistas/microbiología , Adulto , Antibacterianos/administración & dosificación , Técnicas Bacteriológicas , Absceso Encefálico/diagnóstico , Absceso Encefálico/inmunología , Absceso Encefálico/terapia , Infecciones Bacterianas del Sistema Nervioso Central/diagnóstico , Infecciones Bacterianas del Sistema Nervioso Central/inmunología , Infecciones Bacterianas del Sistema Nervioso Central/terapia , Diagnóstico Diferencial , Drenaje , Femenino , Infecciones por Bacterias Grampositivas/diagnóstico , Infecciones por Bacterias Grampositivas/inmunología , Infecciones por Bacterias Grampositivas/terapia , Humanos , Lupus Eritematoso Sistémico/diagnóstico , Lupus Eritematoso Sistémico/inmunología , Nefritis Lúpica/diagnóstico , Nefritis Lúpica/inmunología , Vasculitis por Lupus del Sistema Nervioso Central/diagnóstico , Vasculitis por Lupus del Sistema Nervioso Central/inmunología , Imagen por Resonancia Magnética , Micrococcus luteus/efectos de los fármacos , Micrococcus luteus/inmunología , Infecciones Oportunistas/diagnóstico , Infecciones Oportunistas/inmunología , Infecciones Oportunistas/terapia , Valor Predictivo de las Pruebas , Resultado del TratamientoRESUMEN
Purpose: The aim of this study was to examine cohesion, coaggregation, and coculture between bacteria commonly isolated from contact lens cases. Methods: Staphylococcus epidermidis, Staphylococcus haemolyticus, Micrococcus luteus, and Acinetobacter radioresistens (two strains each) isolated from contact lens cases of two asymptomatic wearers were used in this study. In the cohesion assay, bacteria were grown, washed, and examined by incubating lens cases with two different types of bacteria sequentially and assessing the number of adhered cells of each isolate. The ability of isolates to interfere with the growth of other isolates was tested by growing strains in cocultures for 24 hours and determining the numbers of cells of individual strains. For coaggregation, equal proportions of two bacterial suspensions were mixed and allowed to coaggregate for 24 hours. Inhibition of coaggregation was tested by the addition of lactose (0.06 M) or sucrose (0.06 M) or pronase. Results: The initial adhesion of M. luteus or A. radioresistens significantly (P < 0.05) enhanced the subsequent adhesion of the staphylococci. The addition of A. radioresistens in liquid media significantly (P < 0.05) enhanced the growth of staphylococci. S. epidermidis or S. haemolyticus coaggregated with M. luteus or A. radioresistens. The degree of coaggregation varied between 30% and 54%. The highest coaggregation (54% ± 5%) was seen between A. radioresistens 22-1 and S. epidermidis 22-1, isolated from the same lens case. Only lactose or sucrose treatment of staphylococci could partly inhibit coaggregation of some pairs. Conclusions: Coaggregation, cohesion, and growth promotion may facilitate the process of bacterial colonization of contact lens cases.
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Bacterias/crecimiento & desarrollo , Adhesión Bacteriana/fisiología , Lentes de Contacto/microbiología , Contaminación de Equipos , Acinetobacter/crecimiento & desarrollo , Acinetobacter/aislamiento & purificación , Bacterias/aislamiento & purificación , Técnicas Bacteriológicas , Micrococcus luteus/crecimiento & desarrollo , Micrococcus luteus/aislamiento & purificación , Staphylococcus epidermidis/crecimiento & desarrollo , Staphylococcus epidermidis/aislamiento & purificación , Staphylococcus haemolyticus/crecimiento & desarrollo , Staphylococcus haemolyticus/aislamiento & purificaciónRESUMEN
Wastewater-algal biomass is a promising option to biofuel production. However, microbial contaminants constitute a substantial barrier to algal biofuel yield. A series of algal strains, Nannochloris oculata and Chlorella vulgaris samples (n = 30), were purchased from the University of Texas, and were used for both stock flask cultures and flat-panel vertical bioreactors. A number of media were used for isolation and differentiation of potential contaminants according to laboratory standards (CLSI). Conventional PCR amplification was performed followed by 16S rDNA sequencing to identify isolates at the species level. Nanotherapeutics involving a nanomicellar combination of natural chitosan and zinc oxide (CZNPs) were tested against the microbial lytic groups through Minimum Inhibitory Concentration (MIC) tests and Transmission Electronic Microscopy (TEM). Results indicated the presence of Pseudomonas spp., Bacillus pumilus/ safensis, Cellulosimicrobium cellulans, Micrococcus luteus and Staphylococcus epidermidis strains at a substantial level in the wastewater-fed algal reactors. TEM confirmed the effectiveness of CZNPs on the lytic group while the average MICs (mg/mL) detected for the strains, Pseudomonas spp, Micrococcus luteus, and Bacillus pumilus were 0.417, 3.33, and 1.458, respectively. Conclusively, CZNP antimicrobials proved to be effective as inhibitory agents against currently identified lytic microbial group, did not impact algae cells, and shows promise for in situ interventions.
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Biotecnología/instrumentación , Quitosano/farmacología , Aguas Residuales/microbiología , Óxido de Zinc/farmacología , Bacillus pumilus/efectos de los fármacos , Bacillus pumilus/aislamiento & purificación , Biocombustibles , Biomasa , Reactores Biológicos/microbiología , Biotecnología/métodos , Chlorella vulgaris , Chlorophyta , Pruebas de Sensibilidad Microbiana , Micrococcus luteus/efectos de los fármacos , Micrococcus luteus/aislamiento & purificación , Nanotecnología/instrumentación , Nanotecnología/métodos , Pseudomonas/efectos de los fármacos , Pseudomonas/aislamiento & purificación , Staphylococcus epidermidis/efectos de los fármacos , Staphylococcus epidermidis/aislamiento & purificaciónRESUMEN
Bacterial infections remain a significant challenge in biomedicine and environment safety. Increasing worldwide demand for point-of-care techniques and increasing concern on their safe development and use, require a simple and sensitive bioanalysis for pathogen detection. However, this goal is not yet achieved. A design for fluorescein isothiocyanate-labeled lysozyme (FITC-LYZ), which provides quantitative binding information for gram-positive bacteria, Micrococcus luteus, and detects pathogen concentration, is presented. The functional lysozyme is used not only as the pathogenic detection platform, but also as a tracking reagent for microbial population in antibacterial tests. A nonlinear relationship between the system response and the logarithm of the bacterial concentration was observed in the range of 1.2×10(2)-1.2×10(5) cfu mL(-1). The system has a potential for further applications and provides a facile and simple method for detection of pathogenic bacteria. Meanwhile, the fluorescein isothiocyanate -labeled lysozyme is also employed as the tracking agent for antibacterial dynamic assay, which show a similar dynamic curve compared with UV-vis test.
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Técnicas Biosensibles/métodos , Escherichia coli/aislamiento & purificación , Micrococcus luteus/aislamiento & purificación , Muramidasa/química , Técnicas Biosensibles/economía , Fluoresceína-5-Isotiocianato/química , Límite de DetecciónRESUMEN
To date, little is known about existing relationships between mussels and bacteria in hydrocarbon-contaminated marine environments. The aim of this study is to find crude oil degrading bacteria in some mussels at the Persian Gulf. Twenty eight crude oil degrading bacteria were isolated from three mussels species collected from oil contaminated area at Persian Gulf. According to high growth and degradation of crude oil four strains were selected between 28 isolated strains for more study. Determination the nucleotide sequence of the gene encoding for 16S rRNA show that these isolated strains belong to: Shewanella algae isolate BHA1, Micrococcus luteus isolate BHA7, Pseudoalteromonas sp. isolate BHA8 and Shewanella haliotis isolate BHA35. The residual crude oil in culture medium was analysis by Gas Chromatography (GC). The results confirmed that these strains can degrade: 47.24%, 66.08%, 27.13% and 69.17% of crude oil respectively. These strains had high emulsification activity and biosurfactant production. Also, the effects of some factors on crude oil degradation by isolated strains were studied. The results show that the optimum concentration of crude oil was 2.5% and the best degradation take place at 12% of salinity. This research is the first reports on characterization of crude oil degrading bacteria from mussels at Persian Gulf and by using of these bacteria in the field the effect of oil pollution can be reduce on this marine environment.
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Bivalvos/microbiología , Micrococcus luteus/aislamiento & purificación , Contaminación por Petróleo/análisis , Petróleo/análisis , Pseudoalteromonas/aislamiento & purificación , Shewanella/aislamiento & purificación , Animales , Biodegradación Ambiental , Bivalvos/metabolismo , Océano Índico , Contaminación por Petróleo/prevención & control , ARN Ribosómico 16S/genéticaRESUMEN
Keratinolytic microorganisms have become the subject of scientific interest due to their ability to biosynthesize specific keratinases and their prospective application in keratinic waste management. Among several bacterial classes, actinobacteria remain one of the most important sources of keratin-degrading strains, however members of the Micrococcaceae family are rarely scrutinized in regard to their applicatory keratinolytic potential. The tested Micrococcus sp. B1pz isolate from poultry feather waste was identified as M. luteus. The strain, grown in the medium with 1-2% chicken feathers and a yeast extract supplement, produced keratinases of 32 KU and lower level of proteases, 6 PU. It was capable to effectively decompose feathers or "soft" keratin of stratum corneum, in contrast to other "hard" hair-type keratins. The produced keratinolytic enzymes were mainly a combination of alkaline serine or thiol proteases, active at the optimum pH 9.4, 55 °C. Four main protease fractions of 62, 185, 139 and 229 kDa were identified in the crude culture fluid. The research on the auxiliary role of reducing factors revealed that reducing sulfur compounds could be applied in keratinolysis enhancement during enzymatic digestion of keratin, rather than in culture conditions. The presented M. luteus isolate exhibits a significant keratinolytic potential, which determines its feasible applicatory capacity towards biodegradation of poultry by-products or formulation of keratin-based feed components.
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Queratinas/metabolismo , Micrococcus luteus/enzimología , Micrococcus luteus/metabolismo , Péptido Hidrolasas/metabolismo , Animales , Biodegradación Ambiental , Pollos/microbiología , Plumas/microbiología , Micrococcus luteus/aislamiento & purificación , NADH NADPH Oxidorreductasas/metabolismo , Oxidación-Reducción , Aves de Corral/microbiología , Compuestos de Azufre/metabolismo , Administración de ResiduosRESUMEN
BACKGROUND: Sterilized packaging systems are designed to maintain the sterility of surgical instruments and devices from the time of sterilization until use. This study evaluated the effectiveness of rigid containers versus wrapped instrument trays, sterilized using North American sterilization protocols, to maintain a sterile internal environment poststerilization when challenged with aerosolized bacteria under dynamic environmental conditions. METHODS: Using a custom aerosol chamber, 111 rigid containers of various durations of use (unused, used <5 years, used 5-9 years) and 161 wrapped trays using 3 grades of sterilization wrap were challenged with ~10(2) colony-forming units per liter of air containing aerosolized Micrococcus luteus with a count median particle size of 1 µm, while simultaneously experiencing air volume exchanges due to vacuum cycles-two 1-psi cycles, three 0.7-psi cycles, and three 0.4-psi cycles-to simulate air exchange events occurring during the sterilization, transportation, and storage of sterilized instrument trays in health care facilities. RESULTS: Of 111 rigid containers tested, 97 (87%) demonstrated bacterial ingress into the container. Of 161 wrapped trays, 0 (0%) demonstrated bacterial ingress into the tray. Contamination rates of rigid containers increased significantly with increasing duration of use. CONCLUSIONS: In this study using a dynamic bacterial aerosol challenge, sterilized wrapped trays demonstrated significantly greater protection than sterilized rigid containers against the ingress of airborne bacteria.
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Esterilización , Equipo Quirúrgico/microbiología , Aerosoles , Fómites , Micrococcus luteus/aislamiento & purificación , América del Norte , Embalaje de Productos/métodosRESUMEN
Keratinolytic microorganisms have become the subject of scientific interest due to their ability to biosynthesize specific keratinases and their prospective application in keratinic waste management. Among several bacterial classes, actinobacteria remain one of the most important sources of keratin-degrading strains, however members of the
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Animales , Queratinas/metabolismo , Micrococcus luteus/enzimología , Micrococcus luteus/metabolismo , Péptido Hidrolasas/metabolismo , Biodegradación Ambiental , Pollos/microbiología , Plumas/microbiología , Micrococcus luteus/aislamiento & purificación , NADH NADPH Oxidorreductasas/metabolismo , Oxidación-Reducción , Aves de Corral/microbiología , Compuestos de Azufre/metabolismo , Administración de ResiduosRESUMEN
OBJECTIVES: Infection remains a leading cause of post-transfusion mortality and morbidity. Bacterial contamination is, however, detected in less than 0.1% of blood units tested. The aim of the study was to identify viable bacteria in standard blood-pack units, with particular focus on bacteria from the oral cavity, and to determine the distribution of bacteria revealed in plasma and in the red blood cell (RBC)-fraction. DESIGN: Cross-sectional study. Blood were separated into plasma and RBC-suspensions, which were incubated anaerobically or aerobically for 7 days on trypticase soy blood agar (TSA) or blue lactose plates. For identification colony PCR was performed using primers targeting 16S rDNA. SETTING: Blood donors attending Capital Region Blood Bank, Copenhagen University Hospital, Rigshospitalet, Hvidovre, Denmark, October 29th to December 10th 2013. PARTICIPANTS: 60 donors (≥50 years old), self-reported medically healthy. RESULTS: Bacterial growth was observed on plates inoculated with plasma or RBCs from 62% of the blood donations. Growth was evident in 21 (35%) of 60 RBC-fractions and in 32 (53%) of 60 plasma-fractions versus 8 of 60 negative controls (p = 0.005 and p = 2.6x10-6, respectively). Propionibacterium acnes was found in 23% of the donations, and Staphylococcus epidermidis in 38%. The majority of bacteria identified in the present study were either facultative anaerobic (59.5%) or anaerobic (27.8%) species, which are not likely to be detected during current routine screening. CONCLUSIONS: Viable bacteria are present in blood from donors self-reported as medically healthy, indicating that conventional test systems employed by blood banks insufficiently detect bacteria in plasma. Further investigation is needed to determine whether routine testing for anaerobic bacteria and testing of RBC-fractions for adherent bacteria should be recommended.
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Eritrocitos/microbiología , Donantes de Sangre , Estudios Transversales , Humanos , Viabilidad Microbiana , Micrococcus luteus/crecimiento & desarrollo , Micrococcus luteus/aislamiento & purificación , Persona de Mediana Edad , Propionibacterium acnes/crecimiento & desarrollo , Propionibacterium acnes/aislamiento & purificación , Staphylococcus epidermidis/crecimiento & desarrollo , Staphylococcus epidermidis/aislamiento & purificaciónRESUMEN
Phylogenetic analysis of aerobic chemoorganotrophic bacteria of the two extreme regions (Dead Sea and West Antarctic) was performed on the basis of the nucleotide sequences of the 16S rRNA gene. Thermotolerant and halotolerant spore-forming bacteria 7t1 and 7t3 of terrestrial ecosystems Dead Sea identified as Bacillus licheniformis and B. subtilis subsp. subtilis, respectively. Taking into account remote location of thermotolerant strain 6t1 from closely related strains in the cluster Staphylococcus, 6t1 strain can be regarded as Staphylococcus sp. In terrestrial ecosystems, Galindez Island (Antarctic) detected taxonomically diverse psychrotolerant bacteria. From ornithogenic soil were isolated Micrococcus luteus O-1 and Microbacterium trichothecenolyticum O-3. Strains 4r5, 5r5 and 40r5, isolated from grass and lichens, can be referred to the genus Frondihabitans. These strains are taxonomically and ecologically isolated and on the tree diagram form the joint cluster with three isolates Frondihabitans sp., isolated from the lichen Austrian Alps, and psychrotolerant associated with plants F. cladoniiphilus CafT13(T). Isolates from black lichen in the different stationary observation points on the south side of a vertical cliff identified as: Rhodococcus fascians 181n3, Sporosarcina aquimarina O-7, Staphylococcus sp. 0-10. From orange biofilm of fouling on top of the vertical cliff isolated Arthrobacter sp. 28r5g1, from the moss-- Serratia sp. 6r1g. According to the results, Frondihabitans strains most frequently encountered among chemoorganotrophic aerobic bacteria in the Antarctic phytocenoses.
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ADN Bacteriano/aislamiento & purificación , Filogenia , ARN Ribosómico 16S/aislamiento & purificación , Agua de Mar/microbiología , Adaptación Fisiológica , Aerobiosis , Regiones Antárticas , Arthrobacter/clasificación , Arthrobacter/genética , Arthrobacter/aislamiento & purificación , Bacillus subtilis/clasificación , Bacillus subtilis/genética , Bacillus subtilis/aislamiento & purificación , Frío , ADN Bacteriano/clasificación , ADN Bacteriano/genética , Genes de ARNr , Calor , Región Mediterránea , Micrococcus luteus/clasificación , Micrococcus luteus/genética , Micrococcus luteus/aislamiento & purificación , ARN Ribosómico 16S/clasificación , ARN Ribosómico 16S/genética , Rhodococcus/clasificación , Rhodococcus/genética , Rhodococcus/aislamiento & purificación , Tolerancia a la Sal , Serratia/clasificación , Serratia/genética , Serratia/aislamiento & purificación , Sporosarcina/clasificación , Sporosarcina/genética , Sporosarcina/aislamiento & purificación , Staphylococcus/clasificación , Staphylococcus/genética , Staphylococcus/aislamiento & purificaciónRESUMEN
Green synthesis of metallic silver nanoparticles has attracted nowadays and alternative to physical and chemical approaches. In the present study, silver nanoparticles (AgNPs) were synthesized from leaf extract of Mimusops elengi, L. at room temperature. Formation of stable AgNPs at 1mM concentrations of silver nitrate (AgNO3) typically gave spherical shape particles with diameter range from 55 to 83nm. The kinetic properties of particle formation were proportional to the effect of concentration of AgNO3 solution. In order to identify the compounds responsible for the bioreduction of Ag(+) ion and the stabilization of AgNPs produced, the functional group present in Mimusops elengi, L. leaf extract was investigated using FTIR. The formation of nanoparticle was confirmed using the surface plasmon resonance band shown in UV-vis spectrophotometer. The topography and morphology of the particles were determined using scanning electron microscopy. The crystalline nature of nanoparticles was confirmed from the XRD pattern. Furthermore these green synthesized AgNPs were found to show higher antimicrobial efficacy against multi drug resistant clinical isolates.
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Antibacterianos/síntesis química , Nanopartículas del Metal/química , Mimusops/química , Extractos Vegetales/química , Hojas de la Planta/química , Plata/química , Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple , Tecnología Química Verde , Humanos , Cinética , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/crecimiento & desarrollo , Klebsiella pneumoniae/aislamiento & purificación , Micrococcus luteus/efectos de los fármacos , Micrococcus luteus/crecimiento & desarrollo , Micrococcus luteus/aislamiento & purificación , Oxidación-Reducción , Tamaño de la Partícula , Espectroscopía Infrarroja por Transformada de Fourier , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Staphylococcus aureus/aislamiento & purificación , Resonancia por Plasmón de Superficie , TemperaturaRESUMEN
This work presents the synthesis of bacteria-mediated bioimprinted films for selective bacterial detection. Marine pathogen sulfate-reducing bacteria (SRB) were chosen as the template bacteria. Chitosan (CS) doped with reduced graphene sheets (RGSs) was electrodeposited on an indium tin oxide electrode, and the resulting RGSs-CS hybrid film served as a platform for bacterial attachment. The electrodeposition conditions were optimized to obtain RGSs-CS hybrid films with excellent electrochemical performance. A layer of nonconductive CS film was deposited to embed the pathogen, and acetone was used to wash away the bacterial templates. Electrochemical impedance spectroscopy was performed to characterize the stepwise modification process and monitor the SRB population. Faradic impedance measurements revealed that the charge transfer resistance (R(ct)) increased with increased SRB concentration. A linear relationship between ΔR(ct) and the logarithm of SRB concentration was obtained within the concentration range of 1.0×10(4)cfum L(-1) to 1.0×10(8)cfum L(-1). The impedimetric sensor showed good selectivity towards SRB based on size and shape. Hence, selectivity for bacterial detection can be improved if the bioimprinting technique is combined with other bio-recognition elements.