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1.
PLOS Glob Public Health ; 4(8): e0003406, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39173045

RESUMEN

BACKGROUND: The COVID-19 pandemic has reshaped healthcare delivery worldwide. OBJECTIVE: To explore potential changes in the reasons for visits and modality of care in primary care settings through the International Consortium of Primary Care Big Data Researchers (INTRePID). METHODS: We conducted a cross-sectional, retrospective study from 2018-2021. We examined visit volume, modality, and reasons for visits to primary care in Argentina, Australia, Canada, China, Peru, Norway, Singapore, Sweden, and the USA. The analysis involved a comparison between the pre-pandemic and pandemic periods. RESULTS: There were more than 215 million visits from over 38 million patients during the study period in INTRePID primary care settings. Most INTRePID countries experienced a decline in monthly visit rates during the first year of the pandemic, with rate ratios (RR) and 95% confidence intervals (CI) ranging from RR:0.57 (95%CI:0.49-0.66) to RR:0.90 (95%CI:0.83-0.98), except for in Canada (RR:0.99, 95%CI:0.94-1.05) and Norway (RR:1.00, 95%CI:0.92-1.10), where rates remained stable and in Australia where rates increased (RR:1.19, 95%CI:1.11-1.28). Argentina, China, and Singapore had limited or no adoption of virtual care, whereas the remaining INTRePID countries varied in the extent of virtual care utilization. In Peru, virtual visits accounted for 7.34% (95%CI:7.33%-7.35%) of all interactions in the initial year of the pandemic, dipping to 5.22% (95%CI:5.21%-5.23%) in the subsequent year. However, in Canada 75.30% (95%CI:75.20%-75.40%) of the visits in the first year were virtual, decreasing to 62.77% (95%CI:62.66%-62.88%) in the second year. Diabetes, hypertension and/or hyperlipidemia and general health exams were in the top 10 reasons for visits in 2019 for all countries. Anxiety, depression and/or other mental health related reasons were among the top 10 reasons for virtual visits in all countries that had virtual care. CONCLUSIONS: The pandemic resulted in changes in reasons for visits to primary care, with virtual care mitigating visit volume disruptions in many countries.

2.
Front Med (Lausanne) ; 11: 1343646, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38952865

RESUMEN

Objectives: The majority of patients with respiratory illness are seen in primary care settings. Given COVID-19 is predominantly a respiratory illness, the INTernational ConsoRtium of Primary Care BIg Data Researchers (INTRePID), assessed the pandemic impact on primary care visits for respiratory illnesses. Design: Definitions for respiratory illness types were agreed on collectively. Monthly visit counts with diagnosis were shared centrally for analysis. Setting: Primary care settings in Argentina, Australia, Canada, China, Norway, Peru, Singapore, Sweden and the United States. Participants: Over 38 million patients seen in primary care settings in INTRePID countries before and during the pandemic, from January 1st, 2018, to December 31st, 2021. Main outcome measures: Relative change in the monthly mean number of visits before and after the onset of the pandemic for acute infectious respiratory disease visits including influenza, upper and lower respiratory tract infections and chronic respiratory disease visits including asthma, chronic obstructive pulmonary disease, respiratory allergies, and other respiratory diseases. Results: INTRePID countries reported a marked decrease in the average monthly visits for respiratory illness. Changes in visits varied from -10.9% [95% confidence interval (CI): -33.1 to +11.3%] in Norway to -79.9% (95% CI: -86.4% to -73.4%) in China for acute infectious respiratory disease visits and - 2.1% (95% CI: -12.1 to +7.8%) in Peru to -59.9% (95% CI: -68.6% to -51.3%) in China for chronic respiratory illness visits. While seasonal variation in allergic respiratory illness continued during the pandemic, there was essentially no spike in influenza illness during the first 2 years of the pandemic. Conclusion: The COVID-19 pandemic had a major impact on primary care visits for respiratory presentations. Primary care continued to provide services for respiratory illness, although there was a decrease in infectious illness during the COVID pandemic. Understanding the role of primary care may provide valuable information for COVID-19 recovery efforts and planning for future global emergencies.

3.
Chemosphere ; 337: 139270, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37343638

RESUMEN

Soil contamination caused by pesticides poses a significant environmental challenge, and addressing it requires effective solutions. Bioremediation, combining the utilization of slurry-bioreactors and microbial consortia, emerges as an appropiated strategy to tackle this issue. Therefore, this research evaluated the chlordane (CLD) removal efficiency by a Streptomyces consortium through bioaugmentation of polluted soils, and slurry-bioreactors. For that, a Streptomyces defined consortium with CLD removal abilities was inoculated in soil microcosms and soil-slurry bioreactors (SB), with (SB-TSB) and without stimulation (SB-water). In soil, CLD presence has no negative effect on consortium growth. This was supported by comparing its duplication time (7.48 ± 0.14 h) with the obtained in the biotic control (7.45 ± 0.04 h). Furthermore, 17% of pesticide removal by microbial action was detected in the treated microcosms. In SB, the microbial development was not affected by the pesticide presence. In SB-TSB, the microbial growth was higher than in SB-water. This was supported by its lesser duplication time (7.27 ± 0.17 h) with respect to the non-stimulated systems (10.88 ± 0.29 h). However, SB-water showed the highest CLD removal ability (34.8%), with a concomitant increase in the chloride ion release. In the phytotoxicity test, the vigor index showed that the bioremediation in SB-water did not exert adverse effects greater than those generated by the CLD. Indeed, the root length increased after the treatment. These findings demonstrate the versatility of the Streptomyces consortium to remediate solid and semi-solid matrices impacted with pesticides, and the advantage of using bioaugmented SB to enhance the pollutants removal and accelerating the clean-up time required.


Asunto(s)
Actinobacteria , Plaguicidas , Contaminantes del Suelo , Streptomyces , Clordano , Contaminantes del Suelo/análisis , Biodegradación Ambiental , Reactores Biológicos , Suelo , Microbiología del Suelo
4.
Res Microbiol ; 174(4): 104028, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36638934

RESUMEN

Global industrialization and natural resources extraction have left cocktails of environmental pollutants. Thus, this work focuses on developing a defined actinobacteria consortium able to restore systems co-contaminated with pollutants occurring in Argentinian environments. In this context, five actinobacteria were tested in solid medium to evaluate antagonistic interactions and tolerance against lindane (LIN), Reactive Black B-V (RBV), phenanthrene (Ph) and Cr(VI). The strains showed absence of antagonism, and most of them tolerated the presence of individual pollutants and their mixtures, except Micromonospora sp. A10. Thus, a quadruple consortium constituted by Streptomyces sp. A5, M7, MC1, and Amycolatopsis tucumanensis DSM 45259T, was tested in liquid systems with individual contaminants. The best microbial growth was observed in the presence of RBV and the lowest on Cr(VI). Removals detected were 83.3%, 65.0% and 52.4% for Ph, RBV and LIN, respectively, with absence of Cr(VI) dissipation. Consequently, the consortium performance was tested against the organic mixture, and a microbial growth similar to the biotic control and a LIN removal increase (61.2%) were observed. Moreover, the four actinobacteria of the consortium survived the mixture bioremediation process. These results demonstrate the potential of the defined actinobacteria consortium as a tool to restore environments co-contaminated with organic pollutants.


Asunto(s)
Actinobacteria , Contaminantes Ambientales , Contaminantes del Suelo , Actinobacteria/genética , Biodegradación Ambiental , Contaminantes del Suelo/análisis , Hexaclorociclohexano , Cromo
5.
J Environ Manage ; 276: 111309, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-32882521

RESUMEN

The scaling-up of lindane-contaminated soils bioremediation from microcosms to mesocosms bioaugmentated with an actinobacteria quadruple culture and biostimulated with sugarcane filter cake (SCFC) was surveyed. Mesocosms of silty loam soil, clayey soil, and sandy soil were polluted with the pesticide, bioaugmented with the mixed culture, biostimulated with adequate amounts of 0.5 mm SCFC particles, and assessed during 63 days maintaining environmental parameters with minimal intervention. Samples were taken to determine residual lindane, heterotrophic microorganisms, enzymatic activities, and bioremediation effectiveness using ecotoxicity tests with Raphanus sativus, Lactuca sativa, and Lycopersicon esculentum. The bioaugmentation and biostimulation of the three soils improved lindane removal, microbial counts, and enzymatic activities, and reduced pesticide T1/2, regarding the values obtained in non-bioremediated controls. The removal process was significantly affected by the soil type, and the highest pesticide dissipation (82.6%) was detected in bioremediated sandy soil. Ecotoxicity tests confirmed the bioremediation success through a rise in the vigor index of seedlings compared to non-treated soils (R. sativus: 12-22%; L. sativa: 12-20%; L. esculentum: 30-45%). Finally, scanning electron microscopy corroborated soil colonization by actinobacteria. Successful scaling-up of the combined application of an actinobacteria quadruple culture and SCFC as an appropriate strategy for restoring lindane-polluted soils at mesocosms-scale was confirmed.


Asunto(s)
Hexaclorociclohexano , Contaminantes del Suelo , Biodegradación Ambiental , Suelo , Microbiología del Suelo , Contaminantes del Suelo/análisis
6.
Rev. méd. hered ; 31(3): 193-200, jul-sep 2020. tab
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1150066

RESUMEN

Resumen El cuidado integral de las personas demanda un entrenamiento para atender problemas crónicos frecuentes en la consulta ambulatoria. Los casos de hipertensión, diabetes mellitus y asma pueden ser abordados mediante modelos de atención en la práctica ambulatoria del primer nivel de atención; uno de ellos es el modelo TOPIC (del inglés: Task-Oriented Processes in Care), el cual permite ordenar la consulta en una secuencia estructurada de cuatro tareas mayores: procesamiento de la información, desarrollo de una adecuada relación médico-paciente-familia, integración de la información y aprendizaje de por vida. El procesamiento de la información contempla cuatro sub-actividades en las que se evalúa las expectativas y preocupaciones del paciente, la gravedad y el control de las condiciones, la adherencia y los efectos adversos del tratamiento, se analiza los daños de órgano blanco propios de la enfermedad y se revisan las comorbilidades. La aplicación de este modelo puede ayudar a los médicos y sus pacientes a ser más eficientes en el manejo de problemas crónicos, teniendo en cuenta el poco tiempo del que se dispone en una consulta ambulatoria.


The integrative approach to care for patients demands training to evaluate frequent chronic problems in the outpatient clinic. Patients with hypertension, diabetes mellitus and asthma can be approach using models of evaluations such as the TOPIC that allows to order the evaluations in a structured sequence of four mayor tasks: processing of the information, development of an adequate physician-patient-family relationship and integrating information and learning for life. Processing information implies four sub-activities in which we evaluate patient´s expectations and concerns, severity and control of conditions, adherence and side effects of treatments focusing on damage to target organs and comorbidities. Applying this model can help physicians and their patients to be more efficient in managing chronic problems considering the short time available for ambulatory care.

7.
Ecotoxicol Environ Saf ; 190: 110143, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31918254

RESUMEN

Lindane is a toxic and persistent organochlorine pesticide, whose extensive use generated its accumulation in different environmental matrices. Bioremediation is a promising technology that can be used combining bioaugmentation and biostimulation processes to soil restoration. The aim of the present work was to determine the conditions of maximum lindane removal by bioaugmentation with an actinobacteria consortium and biostimulation with sugarcane filter cake (SCFC). The assays were carried out on lindane-contaminated silty loam (SLS), clayey (CS), and sandy (SS) soils. Through complete factorial designs, the effects of three abiotic factors (moisture content, proportion and size of SCFC particles) were evaluated on lindane removal. In addition, a response optimizer determined the optimal conditions for pesticide removal in bioaugmented and biostimulated soils, in the range of levels studied for each factor. In these conditions, bioaugmentation of biostimulated soils increased the pesticide removal (SLS: 61.4%, CS: 70.8%, SS: 86.3%), heterotrophic microbial counts, and soil enzymatic activities, and decreased lindane T1/2, regarding the non-bioaugmented biostimulated controls, after 14 days of assay. The values of these parameters confirmed the efficiency of the bioremediation process. Finally, the viability of the four strains was demonstrated at the end of the assay. The results indicate that the simultaneous application of bioaugmentation with the actinobacteria consortium and biostimulation with SCFC constitutes a promising tool for restoring soils contaminated with lindane, by using the optimal conditions obtained through the factorial designs.


Asunto(s)
Biodegradación Ambiental , Hexaclorociclohexano/metabolismo , Microbiología del Suelo , Contaminantes del Suelo/metabolismo , Actinobacteria , Bacterias , Hexaclorociclohexano/análisis , Plaguicidas , Saccharum , Suelo , Contaminantes del Suelo/análisis
8.
Chemosphere ; 238: 124512, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31430718

RESUMEN

Lindane is an organochlorine pesticide that, due to its persistence in the environment, is still detected in different matrices. Bioremediation using actinobacteria consortia proved to be promising for the restoration of contaminated soils. Another alternative to remove xenobiotics is to use agricultural residues, which stimulates microbial activity, increasing its capacity to degrade organic pollutants. The present work studies the coupling of sugarcane bagasse biostimulation and bioaugmentation with the actinobacteria consortium composed of Streptomyces sp. A2, A5, A11 and M7 on lindane removal in different soil types. In this sense, factorial designs with three factors (proportion and size of sugarcane bagasse particles, and moisture content) were employed. A response optimizer identified the combination of factors levels that jointly allowed obtaining the maximum lindane removal in the evaluated conditions. In the optimal conditions, the effect of the bioremediation process on soil microbiota was studied by evaluating different parameters. The highest lindane removal percentages were detected in biostimulated microcosms bioaugmented with the microbial consortium, which were accompanied by a decrease in lindane half-life respect to the controls. Also, the bioaugmentation of biostimulated microcosms increased the microbial counts and enhanced soil enzymatic activities, corroborating the bioremediation process efficiency. The survival of the four actinobacteria at the end of the assay confirmed the ability of all Streptomyces strains to colonize amended soils. Bioremediation by simultaneous application of biostimulation with sugarcane bagasse and bioaugmentation with the actinobacteria consortium, in the optimized conditions, represents an efficient strategy to restore lindane contaminated soils.


Asunto(s)
Hexaclorociclohexano/aislamiento & purificación , Hexaclorociclohexano/metabolismo , Contaminantes del Suelo/aislamiento & purificación , Contaminantes del Suelo/metabolismo , Suelo/química , Streptomyces/efectos de los fármacos , Streptomyces/metabolismo , Biodegradación Ambiental/efectos de los fármacos , Celulosa/química , Celulosa/farmacología , Consorcios Microbianos/efectos de los fármacos , Saccharum/química
9.
Chemosphere ; 173: 359-367, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28126570

RESUMEN

Although the use of organochlorine pesticides (OPs) is restricted or banned in most countries, they continue posing environmental and health concerns, so it is imperative to develop methods for removing them from the environment. This work is aimed to investigate the simultaneous removal of three OPs (lindane, chlordane and methoxychlor) from diverse types of systems by employing a native Streptomyces consortium. In liquid systems, a satisfactory microbial growth was observed accompanied by removal of lindane (40.4%), methoxychlor (99.5%) and chlordane (99.8%). In sterile soil microcosms, the consortium was able to grow without significant differences in the different textured soils (clay silty loam, sandy and loam), both contaminated or not contaminated with the OPs-mixture. The Streptomyces consortium was able to remove all the OPs in sterile soil microcosm (removal order: clay silty loam > loam > sandy). So, clay silty loam soil (CSLS) was selected for next assays. In non-sterile CSLS microcosms, chlordane removal was only about 5%, nonetheless, higher rates was observed for lindane (11%) and methoxychlor (20%). In CSLS slurries, the consortium exhibited similar growth levels, in the presence of or in the absence of the OPs-mixture. Not all pesticides were removed in the same way; the order of pesticide dissipation was: methoxychlor (26%)>lindane (12.5%)>chlordane (10%). The outlines of microbial growth and pesticides removal provide information about using actinobacteria consortium as strategies for bioremediation of OPs-mixture in diverse soil systems. Texture of soils and assay conditions (sterility, slurry formulation) were determining factors influencing the removal of each pesticide of the mixture.


Asunto(s)
Plaguicidas/aislamiento & purificación , Contaminantes del Suelo/aislamiento & purificación , Suelo/química , Streptomyces/metabolismo , Biodegradación Ambiental , Clordano/aislamiento & purificación , Hexaclorociclohexano/aislamiento & purificación , Consorcios Microbianos , Plaguicidas/química , Plaguicidas/metabolismo , Contaminantes del Suelo/química , Contaminantes del Suelo/metabolismo , Streptomyces/crecimiento & desarrollo
10.
J Basic Microbiol ; 56(2): 127-37, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26554742

RESUMEN

Chlordane bioremediation using actinobacteria mixed culture is an attractive clean-up technique. Their ability to produce bioemulsifiers could increase the bioavailability of this pesticide. In order to select a defined actinobacteria mixed culture for chlordane remediation, compatibility assays were performed among six Streptomyces strains. The strains did not show growth inhibition, and they were assayed for chlordane removal, either as pure or as mixed cultures. In pure cultures, all of the strains showed specific dechlorination activity (1.42-24.20 EU mg(-1)) and chlordane removal abilities (91.3-95.5%). The specific dechlorination activity was mainly improved with cultures of three or four microorganisms. The mixed culture consisting of Streptomyces sp. A2-A5-A13 was selected. Their ability to produce bioemulsifiers in the presence of glucose or chlordane was tested, but no significant differences were observed (p > 0.05). However, the stability of the emulsions formed was linked to the carbon source used. Only in chlordane presence the emulsions retained 100% of their initial height. Finally, the selected consortium showed a high degree of sporulation in the pesticide presence. This is the first study on the effects that chlordane exerts on microbe morphology and emulsifier production for a defined mixed culture of Streptomyces with ability to remediate the pesticide.


Asunto(s)
Clordano/metabolismo , Emulsionantes/metabolismo , Consorcios Microbianos , Plaguicidas/metabolismo , Selección Genética , Streptomyces/metabolismo , Biotransformación , Glucosa/metabolismo , Esporas Bacterianas/crecimiento & desarrollo , Streptomyces/crecimiento & desarrollo , Streptomyces/aislamiento & purificación
11.
J Basic Microbiol ; 55(3): 293-302, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24338785

RESUMEN

From an agricultural soil that had received continuous applications of organophosphorus pesticides, 30 actinobacteria strains were isolated. Two strains, identified as Streptomyces sp. AC1-6 and Streptomyces sp. ISP4, were selected because of their tolerance to diazinon and based on the relationship between diazinon removal and microbial growth. In liquid medium with diazinon at concentrations of 25 and 50 mg L(-1), both strains were able to remove approximately 40-50% and 70-90% of the initial diazinon after 24 and 96 h of incubation, respectively. This diazinon removal was accompanied by microbial growth of the strains, an initial pH decrease, and glucose consumption in the liquid medium. Evaluation of the diazinon removal achieved by the free actinobacteria and Streptomyces sp. AC1-6 immobilized on alginate beads revealed that the immobilized cells exhibited a 60% higher diazinon removal compared with the free cells. The reusability of the encapsulated biomass was confirmed, and a diazinon removal rate of more than 50% was obtained after the second batch. This work constitutes one of the few reports that describe Streptomyces strains as diazinon degraders. Given the high diazinon removal found, the streptomycetes exhibit suitable potential as diazinon-degrading actinobacteria for elimination of diazinon from liquid residues.


Asunto(s)
Biodegradación Ambiental , Células Inmovilizadas , Diazinón/metabolismo , Streptomyces/aislamiento & purificación , Streptomyces/metabolismo , Actinobacteria/crecimiento & desarrollo , Actinobacteria/aislamiento & purificación , Actinobacteria/metabolismo , Agricultura , Alginatos , Biomasa , Ácido Glucurónico , Ácidos Hexurónicos , Filogenia , Suelo , Microbiología del Suelo , Contaminantes del Suelo/metabolismo , Streptomyces/crecimiento & desarrollo , Streptomyces/ultraestructura
12.
Biomed Res Int ; 2013: 392573, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23865051

RESUMEN

Pesticides are normally used to control specific pests and to increase the productivity in crops; as a result, soils are contaminated with mixtures of pesticides. In this work, the ability of Streptomyces strains (either as pure or mixed cultures) to remove pentachlorophenol and chlorpyrifos was studied. The antagonism among the strains and their tolerance to the toxic mixture was evaluated. Results revealed that the strains did not have any antagonistic effects and showed tolerance against the pesticides mixture. In fact, the growth of mixed cultures was significantly higher than in pure cultures. Moreover, a pure culture (Streptomyces sp. A5) and a quadruple culture had the highest pentachlorophenol removal percentages (10.6% and 10.1%, resp.), while Streptomyces sp. M7 presented the best chlorpyrifos removal (99.2%). Mixed culture of all Streptomyces spp. when assayed either as free or immobilized cells showed chlorpyrifos removal percentages of 40.17% and 71.05%, respectively, and for pentachlorophenol 5.24% and 14.72%, respectively, suggesting better removal of both pesticides by using immobilized cells. These results reveal that environments contaminated with mixtures of xenobiotics could be successfully cleaned up by using either free or immobilized cultures of Streptomyces, through in situ or ex situ remediation techniques.


Asunto(s)
Consorcios Microbianos , Plaguicidas/aislamiento & purificación , Streptomyces/citología , Streptomyces/metabolismo , Adaptación Fisiológica , Biodegradación Ambiental , Células Inmovilizadas/metabolismo , Cloropirifos/aislamiento & purificación , Pentaclorofenol/aislamiento & purificación , Streptomyces/crecimiento & desarrollo
13.
Int J Mol Sci ; 13(11): 15086-106, 2012 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-23203113

RESUMEN

In the last few decades, highly toxic organic compounds like the organochlorine pesticide (OP) hexachlorocyclohexane (HCH) have been released into the environment. All HCH isomers are acutely toxic to mammals. Although nowadays its use is restricted or completely banned in most countries, it continues posing serious environmental and health concerns. Since HCH toxicity is well known, it is imperative to develop methods to remove it from the environment. Bioremediation technologies, which use microorganisms and/or plants to degrade toxic contaminants, have become the focus of interest. Microorganisms play a significant role in the transformation and degradation of xenobiotic compounds. Many Gram-negative bacteria have been reported to have metabolic abilities to attack HCH. For instance, several Sphingomonas strains have been reported to degrade the pesticide. On the other hand, among Gram-positive microorganisms, actinobacteria have a great potential for biodegradation of organic and inorganic toxic compounds. This review compiles and updates the information available on bacterial removal of HCH, particularly by Streptomyces strains, a prolific genus of actinobacteria. A brief account on the persistence and deleterious effects of these pollutant chemical is also given.


Asunto(s)
Bacterias/metabolismo , Hexaclorociclohexano/metabolismo , Actinobacteria/metabolismo , Biodegradación Ambiental , Microbiología Ambiental , Contaminantes Ambientales/metabolismo , Bacterias Gramnegativas/metabolismo , Hexaclorociclohexano/química , Redes y Vías Metabólicas , Plantas/metabolismo , Plantas/microbiología
14.
J Eukaryot Microbiol ; 52(3): 191-200, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15926994

RESUMEN

The toxic dinoflagellate Alexandrium catenella isolated from fjords in Southern Chile produces several analogues of saxitoxin and has been associated with outbreaks of paralytic shellfish poisoning. Three bacterial strains, which remained in close association with this dinoflagellate in culture, were isolated by inoculating the dinoflagellate onto marine agar. The phenotypically different cultivable bacterial colonies were purified. Their genetic identification was done by polymerase chain reaction amplification of the 16S rRNA genes. Partial sequence analysis suggested that the most probable affiliations were to two bacterial phyla: Proteobacteria and the Cytophaga group. The molecular identification was complemented by morphological data and biochemical profiling. The three bacterial species, when grown separately from phytoplankton cells in high-nutrient media, released algal-lytic compounds together with aminopeptidase, lipase, glucosaminidase, and alkaline phosphatase. When the same bacteria, free of organic nutrients, were added back to the algal culture they displayed no detrimental effects on the dinoflagellate cells and recovered their symbiotic characteristics. This observation is consistent with phylogenetic analysis that reveals that these bacteria correspond to species distinct from other bacterial strains previously classified as algicidal bacteria. Thus, bacterial-derived lytic activities are expressed only in the presence of high-nutrient culture media and it is likely that in situ environmental conditions may modulate their expression.


Asunto(s)
Bacterias/clasificación , Dinoflagelados/microbiología , Animales , Bacterias/genética , Bacterias/aislamiento & purificación , Bacterias/ultraestructura , Técnicas de Tipificación Bacteriana , Cytophaga/clasificación , Cytophaga/genética , Cytophaga/aislamiento & purificación , Citotoxinas/análisis , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Dinoflagelados/ultraestructura , Enzimas/análisis , Eucariontes/microbiología , Datos de Secuencia Molecular , Filogenia , Pseudoalteromonas/clasificación , Pseudoalteromonas/aislamiento & purificación , ARN Ribosómico 16S/genética , Rhodobacteraceae/clasificación , Rhodobacteraceae/aislamiento & purificación , Agua de Mar/microbiología , Análisis de Secuencia de ADN
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