RESUMEN
Environmental operators perform their activities in accordance with the relevant legal provisions; however, this does not mean that they operate at their technological optima using the operational information available. The possible negative effects (odor, noise, etc.) of a sub-optimal operation can be felt first and foremost by those living in the immediate vicinity of the given object. It would be important to make effective use of these citizens feedback (quickly to revealing the root causes) thus minimize negative environmental impact of operations. The solution proposed in this paper is a portal called EnviroMind, which allows citizens feedback to be recorded in an easy, immediate, and structured way via a form and on the other hand, it provides a real-time graphical odor transmission model output in a dashboard to operators. Using this portal as a monitoring system the magnitude of the odor effect could be reduced and a smaller area around the industrial object could be affected. In a landfill monitoring pilot project where this monitoring system was used the decrease in the number of indicated odor observations was 85% and the decrease in maximal distance from landfill to odor detection positions was 45%. It is proposed to use EnviroMind monitoring system for all industrial objects which have a significant odor effect on the environment, because by using it we can make the odor effect visible to operators in real time, thus, the reaction time for solving the problem can be minimized.Implications: monitoring is available online to the surrounding community, the affected population, so that quick responses and interventions are available; in the knowledge of the current technological activity carried out on the site its expected odor effect in the area can be determined, whether a protected area can be reached and what odor concentration is expected; in every 15 minutes model results to accurately track expected odor emission values; possibility of intervention, stopping or modification of the technology steps. Experience and main achievements of portal operation in a landfill monitoring pilot project from recent 3 years: the decreasing number of odor perceptions (the decrease in the number of indicated observations was 85%) and the cessation of odor effects in certain areas (and the decrease in maximal distance from landfill to odor detection positions was 45%).
Asunto(s)
Contaminantes Atmosféricos , Eliminación de Residuos , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Odorantes/análisis , Proyectos Piloto , Eliminación de Residuos/métodos , Instalaciones de Eliminación de ResiduosRESUMEN
The newly isolated strain E1, identified as a Dietzia sp., proved to have an excellent ability to degrade n-C12 to n-C38 alkane components of crude oil. The preferred substrate was the very long-chain alkane n-eicosane at an optimal temperature of 37 degrees C and an optimal pH of 8 under aerobic conditions. The growth and substrate uptake kinetics were monitored during the n-alkane fermentation process, and Dietzia sp. E1 cells were found to possess three distinct levels of cell-surface hydrophobicity. Gas chromatographic/mass spectrometric analysis revealed that intracellular substrate mineralization occurred through the conversion of n-alkane to the corresponding n-alkanal. The monoterminal oxidation pathway was presumably initiated by AlkB and CYP153 terminal alkane hydroxylases, both of their partial coding sequences were successfully detected in the genome of strain E1, a novel member of the Dietzia genus.
Asunto(s)
Actinobacteria/metabolismo , Alcanos/metabolismo , Actinobacteria/genética , Actinobacteria/crecimiento & desarrollo , Biodegradación Ambiental , Citocromo P-450 CYP4A/genética , Cromatografía de Gases y Espectrometría de MasasRESUMEN
Strain T1E, isolated and identified as Brevibacillus thermoruber, and evolutionally distant from the known keratinolytic isolates, proved to have feather-degrading ability. During the 7-day fermentation period, T1E consumed 10 g/l native goose feathers as the sole source of carbon and energy at 50 degrees C under aerobic conditions. The isolate secreted a thermostable, keratinolytic protease, which exhibited activity optimally at pH 6.5, whilst it was inhibited at alkaline pH. The keratin cleavage and catabolism resulted in the accumulation of free aspartic acid and soluble peptides with maximum values of 31.6 and 720 mg/l, respectively. The majority of the fermentation end-products were found to be small oligopeptides with an average molecular mass of 2275 Da.
Asunto(s)
Bacillus/enzimología , Plumas/metabolismo , Péptido Hidrolasas/metabolismo , Animales , Ácido Aspártico/análisis , Bacillus/crecimiento & desarrollo , ADN Ribosómico/genética , Plumas/química , Fermentación , Gansos , Cinética , Péptido Hidrolasas/genética , Péptido Hidrolasas/aislamiento & purificación , ARN Ribosómico 16S/genética , ARN Ribosómico 16S/aislamiento & purificación , Streptomyces/enzimologíaRESUMEN
Mycolicibacterium sp. strain CH28 is a novel bacterial isolate belonging to a group of rapidly growing mycobacteria. Here, we report the draft genome sequence of strain CH28 and provide insights into the genetic background of its potential diisopropyl ether-degrading capability.
RESUMEN
Intestinal dysbiosis is linked to numerous gastrointestinal disorders, including inflammatory bowel diseases. It is a question of debate if coxibs, selective inhibitors of cyclooxygenase (COX)-2, cause dysbiosis. Therefore, in the present study, we aimed to determine the effect of long-term (four weeks) selective inhibition of COX-2 on the small intestinal microbiota in the rat. In order to avoid mucosal damage due to topical effects and inflammation-driven microbial alterations, rofecoxib, a nonacidic compound, was used. The direct inhibitory effect of rofecoxib on the growth of bacteria was ruled out in vitro. The mucosa-sparing effect of rofecoxib was confirmed by macroscopic and histological analysis, as well as by measuring the intestinal levels of cytokines and tight junction proteins. Deep sequencing of bacterial 16S rRNA revealed that chronic rofecoxib treatment had no significant influence on the composition and diversity of jejunal microbiota. In conclusion, this is the first demonstration that long-term selective inhibition of COX-2 by rofecoxib does not cause small intestinal dysbiosis in rats. Moreover, inhibition of COX-2 activity is not likely to be responsible per se for microbial alterations caused by some coxibs, but other drug-specific properties may contribute to it.
Asunto(s)
Inhibidores de la Ciclooxigenasa 2/farmacología , Ciclooxigenasa 2/metabolismo , Disbiosis/patología , Intestino Delgado/enzimología , Intestino Delgado/patología , Lactonas/farmacología , Sulfonas/farmacología , Animales , Bacterias/efectos de los fármacos , Bacterias/crecimiento & desarrollo , Celecoxib/farmacología , Dinoprostona/biosíntesis , Disbiosis/microbiología , Mucosa Gástrica/efectos de los fármacos , Mucosa Gástrica/patología , Microbioma Gastrointestinal/efectos de los fármacos , Masculino , Pruebas de Sensibilidad Microbiana , Ratas Wistar , Factores de TiempoRESUMEN
BACKGROUND: Shigella spp. are Gram-negative intracellular pathogenic bacteria belonging to the family Enterobacteriaceae and can cause bacterial dysentery, a severe diarrheal disease. The pathophysiological impact of the Gram-negative bacteria is highly related to the composition and structural variability of lipopolysaccharides, the major lipoid components of the outer membrane. Out of the 114 genes involved in the lipopolysaccharide biosynthesis pathway, 47 genes are specific to Shigella spp. Changes in the specific genes can lead to loss of the O polysaccharide side chain, resulting in rough (R) type bacteria with increased sensitivity to temperature, or hydrophobic antibiotics. The formation of various different lipopolysaccharides or lipooligosaccharides has been observed previously in a mutant line showing altered biological properties, but the genetic background has not been investigated in detail. RESULTS: The parental strain of the mutant line, Shigella sonnei 4303, was subjected to whole genome sequencing to gain a better insight into the structure and biosynthesis of lipopolysaccharides. The sequencing revealed a 4,546,505 bp long genome including chromosomal and plasmid DNA, and the lipopolysaccharide biosynthesis genes were also identified. A comparison of the genome was performed with the phylogenetically closely related, wild type, well characterized, highly virulent strain, S. sonnei 53G. CONCLUSION: Analysis of the lipopolysaccharide biosynthetic genes helped us to get more insight into the pathogenicity and virulence of the bacteria. The genome revealed high similarities with S. sonnei 53G, which can be used as a standard in characterizing the S. sonnei 4303's R-type isogenic derivatives.
RESUMEN
Strain AR-46, isolated and identified as Acinetobacter haemolyticus, evolutionally distant from the known hydrocarbon-degrading Acinetobacter spp., proved to have excellent long-chain n-alkane-degrading ability. This is the first detailed report on an n-alkane-utilizing strain belonging to this species. The preferred substrate is n-hexadecane, with an optimal temperature of 37 degrees C under aerobic conditions. Five complete and two partial open reading frames were sequenced and correlated with the early steps of monoterminal oxidation-initiated n-alkane mineralization. The encoded protein sequences and the arrangement of these genes displayed high similarity to those found in Acinetobacter sp. M-1, but AR-46 seemed to have only one alkane hydroxylase gene, with a completely different induction profile. Unique behaviour was also observed in n-alkane bioavailability. Substrate uptake occurred through the hydrophobic surface of n-alkane droplet-adhered cells possessing long, thick fimbriae, which were presumed to play a major role in n-alkane solubilization. A majority of the cells was in detached form, with thick, but short fimbriae. These free cells were permanently hydrophilic, unlike the cells of other Acinetobacter strains.
Asunto(s)
Acinetobacter/metabolismo , Alcanos/metabolismo , Acinetobacter/clasificación , Acinetobacter/genética , Cartilla de ADN , ADN Bacteriano/genética , ADN Ribosómico/genética , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Filogenia , ARN Bacteriano/genética , ARN Ribosómico 16S/genética , Especificidad por SustratoRESUMEN
OBJECTIVES: Air quality in the stables is characterized by elevated level of dust and aeroallergens which are supposed to directly cause or exacerbate several respiratory disorders. The most often recognized problem is recurrent airway obstruction (RAO), previously known as chronic obstructive pulmonary disease (COPD). There is some indication that aeroallergens (among them endotoxins) may also cause inflammation in human airways and may exceed safe levels in stables. Monitoring studies have covered mainly the determination of the concentration of respirable particles and of culturable fungi and their toxins. However, these particles do not only directly affect the respiratory system, but might act as a carrier conveying toxic contaminants and biological agents such as bacteria. In a typical, 20-horse Hungarian stable, microbial community of respirable fraction of resuspended dust has been characterized to reveal if these particles convey hazardous pathogenic bacteria, posing risk to either horses or staff. MATERIAL AND METHODS: Resuspended dust was sampled using a mobile instrument. The instrument contains a PARTISOL-FRM model 2000 sampler that was operated at a flow rate of 16.7 l/min and a cyclone separator which collected the particulate matter with an aerodynamic size between 1 µm and 10 µm (PM1-10) fraction. Microbial taxa were identified by culture-independent next generation sequencing (NGS) of variable 16S ribosomal ribonucleic acid (rRNA) gene regions. RESULTS: In total, 1491 different taxa were identified, of them 384 were identified to species level, 961 to genus level. The sample was dominated by common ubiquitous soil and organic material-dwelling taxa. CONCLUSIONS: Pathogens occurred at low abundance, and were represented by mostly facultative human pathogens, with the prevalence of Staphylococcus species.
Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Crianza de Animales Domésticos , Polvo/análisis , Bacterias Gramnegativas/aislamiento & purificación , Bacterias Grampositivas/aislamiento & purificación , Exposición Profesional , Animales , Caballos , HumanosRESUMEN
Nitrate-dependent salicylate degradation by the denitrifying Pseudomonas butanovora was investigated and the molar ratio of the cometabolism under anaerobic circumstances was determined. The bacterium was able to utilize salicylate as an electron donor for the reduction of nitrate. Salicylate was eliminated via catechol, which is degraded by means of catechol 2,3-oxygenases (meta-cleavage), forming 2-hydroxymuconic semialdehyde. The molar ratios of NO(3)(-)-N:salicylate existing during the experiment accorded well with the assumed 1:1 molar ratio. The tolerances of the growth, the salicylate degradation and the denitrification of P. butanovora to various heavy metal ions were also studied. Although the strain was tolerant to Pb(2+) and Cu(2+) up to 1 mM in complete medium, salicylate utilization took place only up to a concentration of 0.1 mM for both heavy metal ions. Of the heavy metal ions investigated, Cd(2+) (at a concentration of 0.05 mM) displayed the highest inhibitory effect on salicylate degradation by P. butanovora.
Asunto(s)
Nitratos/metabolismo , Pseudomonas/metabolismo , Salicilatos/metabolismo , Anaerobiosis , Catecoles/química , Catecoles/metabolismo , Proliferación Celular/efectos de los fármacos , Microbiología Industrial/métodos , Metales Pesados/metabolismo , Metales Pesados/farmacología , Oxigenasas/metabolismo , Pseudomonas/crecimiento & desarrolloRESUMEN
Methylibium sp. strain T29 was isolated from a gasoline-contaminated aquifer and proved to have excellent capabilities in degrading some common fuel oxygenates like methyl tert-butyl ether, tert-amyl methyl ether and tert-butyl alcohol along with other organic compounds. Here, we report the draft genome sequence of M. sp. strain T29 together with the description of the genome properties and its annotation. The draft genome consists of 608 contigs with a total size of 4,449,424 bp and an average coverage of 150×. The genome exhibits an average G + C content of 68.7 %, and contains 4754 protein coding and 52 RNA genes, including 48 tRNA genes. 71 % of the protein coding genes could be assigned to COG (Clusters of Orthologous Groups) categories. A formerly unknown circular plasmid designated as pT29A was isolated and sequenced separately and found to be 86,856 bp long.
RESUMEN
An investigation was made of the effects of variation of the hydraulic retention time (HRT) and the concentrations of three different carbon sources (succinic acid, ethanol and acetic acid) on the denitrification activity of immobilized Pseudomonas butanovora cells. The highest denitrification activity was in all cases measured at a C: N ratio of 6: and a relatively low HRT (2.5 h). The highest denitrification rates were 1.17 kg NO3--N m(-3) d(-1) for succinic acid, 1.63 kg NO3--Nm(-3) d(-1) for ethanol and 1.53kg NO3--Nm(-3) d(-1) for acetic acid. At the same C:N ratios, ethanol and acetic acid proved to be better substrates for the reduction of nitrate and nitrite. The determined optimum C: N ratios were 1.78 +/- 0.31, 0.95 +/- 0.17, 1.76 +/- 0.42 for succinic acid, ethanol and acetic acid, respectively. The optimum C:N ratios for the different substrates did not change in response to an increased flow rate. At a C: N ratio of 3:1 and a HRT of 1.5 h, the immobilized cells did not retain their activity. Apart from the difference in the effectivity between the electron donors, the main influence on the denitrification rate was exerted by the flow rate The results of this study demonstrated that Pseudomonas butanovora can utilize all three of these carbon sources to achieve a high rate of denitrification.
Asunto(s)
Ácido Acético/farmacología , Células Inmovilizadas/metabolismo , Etanol/farmacología , Nitrógeno/metabolismo , Pseudomonas/efectos de los fármacos , Pseudomonas/metabolismo , Ácido Succínico/farmacología , Ácido Acético/metabolismo , Reactores Biológicos , Células Inmovilizadas/efectos de los fármacos , Etanol/metabolismo , Pseudomonas/citología , Ácido Succínico/metabolismo , Factores de TiempoRESUMEN
Pseudomonas butanovora, a novel denitrifying bacterium, was immobilized in composite beads and filled into a reactor system. The pilot bioreactor average denitrification activity was at ethanol-C:nitrate-N ratios of 3:1 and 1.5:1 0.88 and 0.54 kg NO3(-)-Nm(-3) d(-1), respectively. The denitrification was stable in spite of the relatively low hydraulic retention times of 2.47 and 3 h. The nitrate content of the influent was almost completely reduced at the first level of the bioreactor and the nitrite formed underwent reduction in the upper part of the reactor. The experimentally determined optimum ethanol-C:nitrate-N ratio was 1.41 +/- 0.41. In consequence of the aerobic conditions, the acetic acid produced by the oxygenation of ethanol was also detectable in the reactor effluent. The pH of the effluent (7.58) never exceeded the acceptable maximum (8.5). The nitrate removal efficiency of the cells was nearly 1000% at both C:N ratios, and the nitrite content of the effluent was around the prescribed limit throughout the continuous operation. This continuous-flow pilot bioreactor containing immobilized P. butanovora cells proved an efficient denitrification system with a relatively low retention time.
Asunto(s)
Reactores Biológicos , Nitratos/aislamiento & purificación , Nitrógeno/aislamiento & purificación , Pseudomonas , Purificación del Agua/métodos , Nitratos/metabolismo , Nitritos/aislamiento & purificación , Nitritos/metabolismo , Nitrógeno/metabolismo , Suelo , Abastecimiento de AguaRESUMEN
The genetic background of long-chain n-alkane degradation was investigated in detail in strain E1, a member of the genetically unexplored Dietzia genus. A suicide vector carrying a 518-bp alkB fragment was site-specifically integrated into the E1 chromosome, and the full alkB, as well as its chromosomal environment was sequenced after plasmid rescue experiments. Four out of the nine putative genes were strongly induced by long-chain n-alkanes in wild-type E1. ORF4 encoded a natural fusion protein consisting of an integral membrane alkane hydroxylase and a rubredoxin domain. The significance of the alkB-rub gene in n-alkane degradation was investigated in phenotypic tests, and the disruption mutant strain exhibited severely impaired growth on n-C(20) alkane carbon source. The mutation was successfully complemented with the expression of intact AlkB-Rub protein, the full-length form of which was detected by simultaneous immunoblotting. The presented data furnish the first experimental evidence of the in vivo existence of an AlkB-Rub natural fusion protein, which plays a major role in long-chain n-alkane degradation.
Asunto(s)
Actinomycetales/metabolismo , Alcanos/metabolismo , Actinomycetales/química , Actinomycetales/enzimología , Actinomycetales/genética , Alcanos/química , Secuencia de Aminoácidos , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Biodegradación Ambiental , Citocromo P-450 CYP4A/química , Citocromo P-450 CYP4A/genética , Citocromo P-450 CYP4A/metabolismo , Datos de Secuencia Molecular , Alineación de SecuenciaRESUMEN
Ochrobactrum anthropi is a well-known Gram-negative bacterium, with the ability to degrade atrazine, urea-formaldehyde and chlorophenols. Investigation were made of the nitrate and nitrite reduction capacities of the strain in succinate and glucose media, and the tolerance of its denitrification to NaCl and some heavy metals. Succinate proved to be a better carbon source to drive denitrification by O. anthropi. Batch fermentation studies in anaerobic succinate medium indicated reduction capacities of 85.4 +/- 9.1 and 48.6 +/- 5.2 mgh(-1)g(-1) dry cell for NO(3) (-) and NO(2) (-), respectively. The nitrite accumulation of the cells revealed that O. anthropi is a group C denitrifying bacterium. Its growth in DSM 1 broth containing NaCl up to 40 g l(-1) demonstrates that O. anthropi belongs in the group of moderately halophilic bacteria. Despite the fact that 42.5 g NaCl l(-1) caused 50% growth inhibition in DSM 1 broth, the cells in the stationary phase readily tolerated NaCl concentrations up to 100 g l(-1). Complete denitrification was achieved in test media containing 30 g NaCl l(-1) after 1 week and the nitrate reductase retained its activity up to 100 g NaCl l(-1). The cells were tolerant to Hg, Zn, Pb, Cu and Ni, and N(2) was producted at tolerated concentrations of the metal in the cases of Hg and Pb.