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1.
Eur Heart J Imaging Methods Pract ; 2(1): qyae063, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39224100

RESUMO

Aims: Atrial fibrillation (AF) is a common comorbidity in non-ischaemic dilated cardiomyopathy (NIDCM) affecting conventional measures of left atrial (LA) function. We aimed to determine whether LA function analysis could identify patients at higher risk of major cardiovascular events (MACEs). Methods and results: A retrospective study of patients with NIDCM in AF referred to a single centre for transthoracic echocardiography (TTE) between 2015 and 2019. Peak atrial longitudinal strain (PALS) was measured along with LA emptying fraction and LA filling index (LAFI = E wave/PALS). Cox regression analysis was conducted. A total of 153 patients were included [median age 74 years, left ventricular ejection fraction (LVEF) 35%], and 57 (37.3%) had MACE after a median follow-up of 3.2 years. LAFI was the only independent TTE parameter associated with MACE after adjustment for age, diabetes, LVEF, left ventricular global longitudinal strain (LV-GLS), and LA volume index [adjusted hazard ratio (HR) = 1.02 per point increase, P = 0.024], with the best cut-off at ≥15. LAFI ≥15 predicted each of MACE components when separately analysed: MACE HR = 1.95, 95% confidence interval (CI) 1.16-3.30; cardiovascular death HR = 3.68, 95% CI 1.41-9.56, heart failure admission HR = 2.13, 95% CI 1.19-3.80, and ventricular arrhythmia HR = 4.72, 95% CI 1.52-14.67. Higher LAFI was associated with worsening LV-GLS, E/e', systolic pulmonary artery (PA) pressure, tricuspid annular plane systolic excursion, and right ventricular to PA coupling. Conclusion: LA deformation analysis is feasible in patients with NIDCM presenting with AF. LAFI may identify patients at higher risk of MACE and correlates with higher pulmonary pressures and worse right ventricular function, suggesting an elevation of left-sided ventricular pressures in patients with higher LAFI.

2.
Am J Cardiol ; 233: 11-18, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39332511

RESUMO

Nonischemic dilated cardiomyopathy (NIDCM) is associated with an increased risk of atrial fibrillation (AF) and stroke, especially in patients with high CHA2DS2-VASc. We aimed to identify variables associated with incident AF or stroke using left atrial deformation analysis and its prognostic value added to CHA2DS2-VASc score. Patients with NIDCM and left ventricular ejection fraction <50% in sinus rhythm were included between January 2015 and December 2019. Left atrial volume index (LAVI) and atrial strain were used in combination with the CHA2DS2-VAS score to predict ischemic stroke or incident AF. Proportional hazards Cox regression was used to provide hazard ratios (HRs). There were 338 patients included. After a median follow-up of 3.6 years, the end point occurred in 41 patients (12.1%). LAVI outperformed other echocardiographic parameters, with a significant improvement in risk reclassification compared with CHA2DS2-VASc alone (net reclassification index 0.6, increase in Harrell's C from 0.63 to 0.73, p = 0.003), and remained significant after multivariate adjustment. LAVI was associated with both components of the end point separately. The best cutoff for LAVI was 44 ml/m2. LAVI ≥44 ml/m2 increased the risk of the end point among those with CHA2DS2-VASc ≥3 (HR 6.0, 95% confidence interval 2.6 to 13.5) but not in those with CHA2DS2-VASc <3 (HR 1.2, 95% confidence interval 0.3 to 4.5). Competing risk analysis did not alter the results. In conclusion, LAVI might be used to assess the risk of incident AF or stroke in NIDCM. Patients with LAVI ≥44 ml/m2 and CHA2DS2-VASc ≥3 could be at high risk of AF and stroke and may benefit from more intensive surveillance.

3.
Front Microbiol ; 14: 1238779, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37860137

RESUMO

Shifting the bioprospecting targets toward underexplored bacterial groups combined with genome mining studies contributes to avoiding the rediscovery of known compounds by revealing novel, promising biosynthetic gene clusters (BGCs). With the aim of determining the biosynthetic potential of a novel marine bacterium, strain V10T, isolated from the Domitian littoral in Italy, a comparative phylogenomic mining study was performed across related photosynthetic bacterial groups from an evolutionary perspective. Studies on polyphasic and taxogenomics showed that this bacterium constitutes a new species, designated Roseibaca domitiana sp. nov. To date, this genus has only one other validly described species, which was isolated from a hypersaline Antarctic lake. The genomic evolutionary study linked to BGC diversity revealed that there is a close relationship between the phylogenetic distance of the members of the photosynthetic genera Roseibaca, Roseinatronobacter, and Rhodobaca and their BGC profiles, whose conservation pattern allows discriminating between these genera. On the contrary, the rest of the species related to Roseibaca domitiana exhibited an individual species pattern unrelated to genome size or source of isolation. This study showed that photosynthetic strains possess a streamlined content of BGCs, of which 94.34% of the clusters with biotechnological interest (NRPS, PKS, RRE, and RiPP) are completely new. Among these stand out T1PKS, exclusive of R. domitiana V10T, and RRE, highly conserved only in R. domitiana V10T and R. ekhonensis, both categories of BGCs involved in the synthesis of plant growth-promoting compounds and antitumoral compounds, respectively. In all cases, with very low homology with already patented molecules. Our findings reveal the high biosynthetic potential of infrequently cultured bacterial groups, suggesting the need to redirect attention to microbial minorities as a novel and vast source of bioactive compounds still to be exploited.

4.
Soc Work ; 68(2): 131-140, 2023 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-36749060

RESUMO

Few studies have analyzed the existence of homogeneous groups (profiles) in burnout and engagement among professionals, and none in social workers. This study with 448 social workers from Spain mainly examined their profiles in burnout and engagement and the characteristics of each profile in relevant job-related variables. Cluster analyses yielded four distinct profiles: the first, Burned Out, showed high burnout and low engagement; the second, Engaged, exhibited the inverse pattern with low burnout and high engagement; the third, Both, displayed simultaneously high burnout and high engagement; the fourth, Neither, showed low burnout and low engagement. The profiles also differed greatly in work-related variables: job demands (i.e., workload and work--family conflict), job resources (i.e., support from supervisor and coworkers), personal resources (i.e., psychological detachment and relaxation), and outcomes (i.e., intrinsic job satisfaction and intent to leave). The findings support interventions, individual and organizational, tailored to the characteristics of different groups to boost engagement and decrease burnout and turnover.


Assuntos
Esgotamento Profissional , Assistentes Sociais , Humanos , Espanha , Serviço Social , Esgotamento Profissional/psicologia , Conflito Familiar , Satisfação no Emprego , Inquéritos e Questionários
5.
ESC Heart Fail ; 10(2): 1193-1204, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36655614

RESUMO

AIM: Patients with advanced heart failure (AHF) who are not candidates to advanced therapies have poor prognosis. Some trials have shown that intermittent levosimendan can reduce HF hospitalizations in AHF in the short term. In this real-life registry, we describe the patterns of use, safety and factors related to the response to intermittent levosimendan infusions in AHF patients not candidates to advanced therapies. METHODS AND RESULTS: Multicentre retrospective study of patients diagnosed with advanced heart failure, not HT or LVAD candidates. Patients needed to be on the optimal medical therapy according to their treating physician. Patients with de novo heart failure or who underwent any procedure that could improve prognosis were not included in the registry. Four hundred three patients were included; 77.9% needed at least one admission the year before levosimendan was first administered because of heart failure. Death rate at 1 year was 26.8% and median survival was 24.7 [95% CI: 20.4-26.9] months, and 43.7% of patients fulfilled the criteria for being considered a responder lo levosimendan (no death, heart failure admission or unplanned HF visit at 1 year after first levosimendan administration). Compared with the year before there was a significant reduction in HF admissions (38.7% vs. 77.9%; P < 0.0001), unplanned HF visits (22.7% vs. 43.7%; P < 0.0001) or the combined event including deaths (56.3% vs. 81.4%; P < 0.0001) during the year after. We created a score that helps predicting the responder status at 1 year after levosimendan, resulting in a score summatory of five variables: TEER (+2), treatment with beta-blockers (+1.5), Haemoglobin >12 g/dL (+1.5), amiodarone use (-1.5) HF visit 1 year before levosimendan (-1.5) and heart rate >70 b.p.m. (-2). Patients with a score less than -1 had a very low probability of response (21.5% free of death or HF event at 1 year) meanwhile those with a score over 1.5 had the better chance of response (68.4% free of death or HF event at 1 year). LEVO-D score performed well in the ROC analysis. CONCLUSION: In this large real-life series of AHF patients treated with levosimendan as destination therapy, we show a significant decrease of heart failure events during the year after the first administration. The simple LEVO-D Score could be of help when deciding about futile therapy in this population.


Assuntos
Fármacos Cardiovasculares , Insuficiência Cardíaca , Humanos , Simendana , Cardiotônicos/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento , Insuficiência Cardíaca/diagnóstico , Sistema de Registros
6.
Health Soc Work ; 47(4): 244-252, 2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36106992

RESUMO

As a result of secondary exposure to traumatic material, social workers may experience vicarious trauma. However, the analysis of this variable among social workers is scarce. The Vicarious Trauma Scale (VTS) is a brief instrument designed to measure the stress consequence of shared trauma. This study aims to examine the psychometrics of the VTS in a sample of 448 social workers from Spain. The results from the exploratory and confirmatory factor analyses (EFA and CFA) indicated that the VTS has satisfactory psychometric properties. Different indices of internal consistency supported the reliability of the VTS. Both EFA and CFA revealed the existence of two factors, corresponding to the cognitive and affective consequences of secondary exposure to trauma. Finally, the correlations of the VTS with other relevant and well-known job variables (workload, work-family conflict, detachment, supervisor support, burnout, and engagement) followed the expected pattern, and the VTS differentiated the social workers by their trauma caseload. Therefore, the VTS can be considered an adequate screening method of social workers' vicarious trauma, and its application recommended to examine the possible risk and protective factors and consequences.


Assuntos
Fadiga de Compaixão , Humanos , Psicometria , Assistentes Sociais , Espanha , Reprodutibilidade dos Testes , Inquéritos e Questionários
7.
Health Soc Work ; 47(3): 195-204, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35640143

RESUMO

As a reaction to specific job stressors, social workers can experience job burnout. The job demands-resources theory posits that personal characteristics would mediate the influence of job stressors on either burnout or engagement. Within this framework, this cross-sectional research aimed to analyze the relationships between work-family interferences (as predictors), self-care practices (as mediators), and burnout and engagement (as outcomes). The sample included 437 graduate social workers from Spain. Structural equation modeling showed that family-work and work-family conflicts negatively predicted self-care practices and positively predicted burnout. Professional and personal self-care practices positively predicted engagement, negatively predicted burnout, and attenuated the impact of work-family interferences on burnout and engagement. To the authors' knowledge, the present article is the first to test the job demands-resources theory with these variables on social workers. The findings support interventions for social work students and professionals enhancing self-care practices to promote engagement and to reduce burnout, and highlight the need to decrease job stressors and enhance job resources for social workers.


Assuntos
Esgotamento Profissional , Assistentes Sociais , Estudos Transversais , Humanos , Satisfação no Emprego , Autocuidado , Inquéritos e Questionários
8.
Rev Esp Cardiol (Engl Ed) ; 75(9): 709-716, 2022 Sep.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-34896031

RESUMO

INTRODUCTION AND OBJECTIVES: HeartLogic is a multiparametric algorithm incorporated into implantable cardioverter-defibrillators (ICD). The associated alerts predict impending heart failure (HF) decompensations. Our objective was to analyze the association between alerts and clinical events and to describe the implementation of a protocol for remote management in a multicenter registry. METHODS: We evaluated study phase 1 (the investigators were blinded to the alert state) and phases 2 and 3 (after HeartLogic activation, managed as per local practice and with a standardized protocol, respectively). RESULTS: We included 288 patients from 15 centers. In phase 1, the median observation period was 10 months and there were 73 alerts (0.72 alerts/patient-y), with 8 hospitalizations and 2 emergency room admissions for HF (0.10 events/patient-y). There were no HF hospitalizations outside the alert period. In the active phases, the median follow-up was 16 (95%CI, 15-22) months and there were 277 alerts (0.89 alerts/patient-y); 33 were associated with HF hospitalizations or HF death (n=6), 46 with minor decompensations, and 78 with other events. The unexplained alert rate was 0.39 alerts/patient-y. Outside the alert state, there was only 1 HF hospitalization and 1 minor HF decompensation. Most alerts (82% in phase 2 and 81% in phase 3; P=.861) were remotely managed. The median NT-proBNP value was higher within than outside the alert state (7378 vs 1210 pg/mL; P <.001). CONCLUSIONS: The HeartLogic index was frequently associated with HF-related events and other clinically relevant situations, with a low rate of unexplained events. A standardized protocol allowed alerts to be safely and remotely detected and appropriate action to be taken on them.


Assuntos
Desfibriladores Implantáveis , Insuficiência Cardíaca , Algoritmos , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/terapia , Hospitalização , Humanos , Sistema de Registros
9.
Health Soc Care Community ; 30(4): 1492-1503, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34184366

RESUMO

The treatment of the mentally ill people is a challenge across the world, and different professionals, such as doctors, social workers, psychologists, or nurses, take care of this group. Nonetheless, mental health is not a vocational sector preferred by students and professionals of many of these careers. Research has proposed that professional preference for a patient group would be positively influenced by intergroup contact (quantity and quality) and empathy (perspective-taking), and negatively associated with intergroup anxiety and social distance. However, the evidence testing this proposal was partial and mainly referring to other patient groups such as minorities or immigrants. The major aim of this cross-sectional study was to clarify two research questions referring to mentally ill persons: Do contact and empathy protect undergraduates from intergroup anxiety and social distance and promote professional preference? Do intergroup anxiety and social distance predict professional preference and mediate the influence of contact and empathy in professional preference? A convenience sample of 409 Social Work undergraduates (81% females) from three Spanish universities completed a questionnaire between February and June 2020. Concerning direct relationships, the structural equation model showed that the quantity of contact only predicted intergroup anxiety negatively; quality of contact and empathy negatively predicted intergroup anxiety and social distance; intergroup anxiety positively predicted social distance; intergroup anxiety and social distance negatively predicted professional preference. Concerning mediated relationships, the influence of quality of contact and empathy on social distance was mediated by intergroup anxiety; social distance mediated the relationship of intergroup anxiety with professional preference; both anxiety and distance mediated the influence of quality of contact and empathy in professional preference. These results encourage interventions aimed at enhancing professional preference for mental illness by improving contact, knowledge, and empathy and reducing stigma in students and workers from diverse mental health careers.


Assuntos
Empatia , Transtornos Mentais , Estudos Transversais , Feminino , Humanos , Masculino , Transtornos Mentais/psicologia , Transtornos Mentais/terapia , Serviço Social , Estudantes
10.
Appl Environ Microbiol ; 86(12)2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32276971

RESUMO

Bacillus thuringiensis (Bt) is the most widely used active ingredient for biological insecticides. The composition of δ-endotoxins (Cry and Cyt proteins) in the parasporal crystal determines the toxicity profile of each Bt strain. However, a reliable method for their identification and quantification has not been available, due to the high sequence identity of the genes that encode the δ-endotoxins and the toxins themselves. Here, we have developed an accurate and reproducible mass spectrometry-based method (liquid chromatography-tandem mass spectrometry-multiple reaction monitoring [LC-MS/MS-MRM]) using isotopically labeled proteotypic peptides for each protein in a particular mixture to determine the relative proportion of each δ-endotoxin within the crystal. To validate the method, artificial mixtures containing Cry1Aa, Cry2Aa, and Cry6Aa were analyzed. Determination of the relative abundance of proteins (in molarity) with our method was in good agreement with the expected values. This method was then applied to the most common commercial Bt-based products, DiPel DF, XenTari GD, VectoBac 12S, and Novodor, in which between three and six δ-endotoxins were identified and quantified in each product. This novel approach is of great value for the characterization of Bt-based products, not only providing information on host range, but also for monitoring industrial crystal production and quality control and product registration for Bt-based insecticides.IMPORTANCEBacillus thuringiensis (Bt)-based biological insecticides are used extensively to control insect pests and vectors of human diseases. Bt-based products provide greater specificity and biosafety than broad-spectrum synthetic insecticides. The biological activity of this bacterium resides in spores and crystals comprising complex mixtures of toxic proteins. We developed and validated a fast, accurate, and reproducible method for quantitative determination of the crystal components of Bt-based products. This method will find clear applications in the improvement of various aspects of the industrial production process of Bt. An important aspect of the production of Bt-based insecticides is its quality control. By specifically quantifying the relative proportion of each of the toxins that make up the crystal, our method represents the most consistent and repeatable evaluation procedure in the quality control of different batches produced in successive fermentations. This method can also contribute to the design of specific culture media and fermentation conditions that optimize Bt crystal composition across a range of Bt strains that target different pestiferous insects. Quantitative information on crystal composition should also prove valuable to phytosanitary product registration authorities that oversee the safety and efficacy of crop protection products.


Assuntos
Bacillus thuringiensis/química , Proteínas de Bactérias/isolamento & purificação , Cromatografia Líquida/métodos , Endotoxinas/isolamento & purificação , Proteínas Hemolisinas/isolamento & purificação , Inseticidas/isolamento & purificação , Proteômica/métodos , Espectrometria de Massas em Tandem/métodos , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/química , Endotoxinas/química , Proteínas Hemolisinas/química , Inseticidas/química , Proteoma/química
11.
Animals (Basel) ; 9(12)2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31847230

RESUMO

Digestive disorders are the main cause of economic damage to rabbit farms. This article provides a global and updated overview of the diverse etiological agents causing them, since 757 clinical cases were analyzed during 2018 and 2019-Ninety-five from young rabbits (<15 days old), 117 from preweaning rabbits (15-35 days old), and 545 from growing rabbits. Etiological diagnosis was carried out by bacteriological culture and a set of real time polymerase chain reaction (qPCR) tests for the detection of enteropathogenic Escherichia coli (EPEC), Clostridium spiroforme, C. perfringens, rotavirus A, Bacteroides fragilis, and Eimeria spp. Also, 40 EPEC and 38 non EPEC isolates were investigated for the presence of other colonization factors (afr2, ral, liftA, and paa) by qPCR. EPEC is the most prevalent agent in young rabbits, and although different virulence profiles have been found among EPEC isolates, the liftA+, ral+, and paa+ profile is the most prevalent. C. spiroforme and EPEC are the more frequently detected pathogens in preweaning rabbits, but B. fragilis appears to be a new possible emergent pathogen. In growing rabbits, diverse co-infections between C. spiroforme, Eimeria spp., EPEC, and rotavirus are much more frequent than infections due to only one of them. Other pathogens detected in very few cases are Salmonella spp. and Enterococcus hirae.

12.
Microorganisms ; 7(8)2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31387286

RESUMO

The genus Salinivibrio belongs to the family Vibrionaceae and includes Gram-stain-negative, motile by a polar flagellum, and facultatively anaerobic curved rods. They are halophilic bacteria commonly found in hypersaline aquatic habitats and salted foods. This genus includes five species and two subspecies. A presumed novel species, strain S35T, was previously isolated from the high-altitude volcanic, alkaline, and saline lake Socompa (Argentinean Andes). In this study we carried out a complete taxonomic characterization of strain S35T, including the 16S rRNA gene sequence and core-genome analysis, the average nucleotide identity (ANIb, ANIm, and orthoANI), and in silico DNA-DNA hybridization (GGDC), as well as the phenotypic and chemotaxonomic characterization. It grew at 3%-20% (w/v) NaCl, pH 6-10, and 10-42 °C, with optimum growth at 7.0%-7.5% (w/v) NaCl, pH 8.0, and 37 °C, respectively. Strain S35T was oxidase- and catalase-positive, able to produce acid from D-glucose and other carbohydrates. Hydrolysis of DNA, methyl red test, and nitrate and nitrite reduction were positive. Its main fatty acids were C16:0, C16:1 ω7c and C16:1 ω6c, and C18:1 ω7c and/or C18:1 ω6c. ANI, GGDC, and core-genome analysis determined that strain S35T constitutes a novel species of the genus Salinivibrio, for which the name Salinivibrio socompensis sp. nov. is proposed. The type strain is S35T (= CECT 9634T = BNM 0535T).

13.
Front Microbiol ; 7: 1284, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27597845

RESUMO

We combined nucleic acid-based molecular methods, biogeochemical measurements, and physicochemical characteristics to investigate microbial sedimentary ecosystems of Laguna Tebenquiche, Atacama Desert, Chile. Molecular diversity, and biogeochemistry of hypersaline microbial mats, rhizome-associated concretions, and an endoevaporite were compared with: The V4 hypervariable region of the 16S rRNA gene was amplified by pyrosequencing to analyze the total microbial diversity (i.e., bacteria and archaea) in bulk samples, and in addition, in detail on a millimeter scale in one microbial mat and in one evaporite. Archaea were more abundant than bacteria. Euryarchaeota was one of the most abundant phyla in all samples, and particularly dominant (97% of total diversity) in the most lithified ecosystem, the evaporite. Most of the euryarchaeal OTUs could be assigned to the class Halobacteria or anaerobic and methanogenic archaea. Planctomycetes potentially also play a key role in mats and rhizome-associated concretions, notably the aerobic organoheterotroph members of the class Phycisphaerae. In addition to cyanobacteria, members of Chromatiales and possibly the candidate family Chlorotrichaceae contributed to photosynthetic carbon fixation. Other abundant uncultured taxa such as the candidate division MSBL1, the uncultured MBGB, and the phylum Acetothermia potentially play an important metabolic role in these ecosystems. Lithifying microbial mats contained calcium carbonate precipitates, whereas endoevoporites consisted of gypsum, and halite. Biogeochemical measurements revealed that based on depth profiles of O2 and sulfide, metabolic activities were much higher in the non-lithifying mat (peaking in the least lithified systems) than in lithifying mats with the lowest activity in endoevaporites. This trend in decreasing microbial activity reflects the increase in salinity, which may play an important role in the biodiversity.

14.
Front Microbiol ; 5: 196, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24847316

RESUMO

We analyzed the prokaryotic community structure of a saltern pond with 21% total salts located in Isla Cristina, Huelva, Southwest Spain, close to the Atlantic ocean coast. For this purpose, we constructed a metagenome (designated as IC21) obtained by pyrosequencing consisting of 486 Mb with an average read length of 397 bp and compared it with other metagenomic datasets obtained from ponds with 19, 33, and 37% total salts acquired from Santa Pola marine saltern, located in Alicante, East Spain, on the Mediterranean coast. Although the salinity in IC21 is closer to the pond with 19% total salts from Santa Pola saltern (designated as SS19), IC21 is more similar at higher taxonomic levels to the pond with 33% total salts from Santa Pola saltern (designated as SS33), since both are predominated by the phylum Euryarchaeota. However, there are significant differences at lower taxonomic levels where most sequences were related to the genus Halorubrum in IC21 and to Haloquadratum in SS33. Within the Bacteroidetes, the genus Psychroflexus is the most abundant in IC21 while Salinibacter dominates in SS33. Sequences related to bacteriorhodopsins and halorhodopsins correlate with the abundance of Haloquadratum in Santa Pola SS19 to SS33 and of Halorubrum in Isla Cristina IC21 dataset, respectively. Differences in composition might be attributed to local ecological conditions since IC21 showed a decrease in the number of sequences related to the synthesis of compatible solutes and in the utilization of phosphonate.

15.
Appl Environ Microbiol ; 80(13): 3850-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24747894

RESUMO

Recent metagenomic studies on saltern ponds with intermediate salinities have determined that their microbial communities are dominated by both Euryarchaeota and halophilic bacteria, with a gammaproteobacterium closely related to the genera Alkalilimnicola and Arhodomonas being one of the most predominant microorganisms, making up to 15% of the total prokaryotic population. Here we used several strategies and culture media in order to isolate this organism in pure culture. We report the isolation and taxonomic characterization of this new, never before cultured microorganism, designated M19-40(T), isolated from a saltern located in Isla Cristina, Spain, using a medium with a mixture of 15% salts, yeast extract, and pyruvic acid as the carbon source. Morphologically small curved cells (young cultures) with a tendency to form long spiral cells in older cultures were observed in pure cultures. The organism is a Gram-negative, nonmotile bacterium that is strictly aerobic, non-endospore forming, heterotrophic, and moderately halophilic, and it is able to grow at 10 to 25% (wt/vol) NaCl, with optimal growth occurring at 15% (wt/vol) NaCl. Phylogenetic analysis based on 16S rRNA gene sequence comparison showed that strain M19-40(T) has a low similarity with other previously described bacteria and shows the closest phylogenetic similarity with species of the genera Alkalilimnicola (94.9 to 94.5%), Alkalispirillum (94.3%), and Arhodomonas (93.9%) within the family Ectothiorhodospiraceae. The phenotypic, genotypic, and chemotaxonomic features of this new bacterium showed that it constitutes a new genus and species, for which the name Spiribacter salinus gen. nov., sp. nov., is proposed, with strain M19-40(T) (= CECT 8282(T) = IBRC-M 10768(T) = LMG 27464(T)) being the type strain.


Assuntos
Ectothiorhodospiraceae/classificação , Ectothiorhodospiraceae/isolamento & purificação , Microbiologia Ambiental , Aerobiose , Análise por Conglomerados , DNA Arqueal/química , DNA Arqueal/genética , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Ectothiorhodospiraceae/genética , Ectothiorhodospiraceae/fisiologia , Locomoção , Metagenômica , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Cloreto de Sódio/metabolismo , Espanha
16.
FEMS Microbiol Ecol ; 88(3): 623-35, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24661078

RESUMO

A metagenome was obtained by pyrosequencing the total prokaryotic DNA from the water of a pond with intermediate salinity (13% salts) from a saltern located in Santa Pola, Spain. We analyzed and compared the phylogenomic and metabolic diversity of this saltern pond with respect to other two metagenomes obtained previously from the same saltern (ponds with 19% and 37% salts, respectively) and two reference metagenomes from marine and coastal lagoon habitats. A large microbial diversity, representing seven major higher taxa (Euryarchaeota, Gammaproteobacteria, Alphaproteobacteria, Actinobacteria, Bacteroidetes, Verrucomicrobia and Betaproteobacteria), was found. However, most sequences (57%) were not assigned to any previously described genus. Principal component analysis of tetranucleotide frequencies of assembled contigs showed the presence of new groups of Euryarchaeota, different from those previously described but related to Haloquadratum walsbyi and other members of the Halobacteriaceae. Besides, some new Gammaproteobacteria, several closely related to the recently isolated bacterium 'Spiribacter salinus' were observed. Metabolically, the nitrogen and carbon cycles appear to be very simplified in this extreme habitat. Light is extensively used as energy source by bacteriorhodopsins and other rhodopsins. Microorganisms known to use the 'salt-in' strategy are probably able to combine the accumulation of potassium ions and of compatible solutes.


Assuntos
Archaea/classificação , Bactérias/classificação , Lagoas/microbiologia , Archaea/genética , Archaea/isolamento & purificação , Archaea/metabolismo , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Ecossistema , Euryarchaeota/classificação , Euryarchaeota/genética , Gammaproteobacteria/classificação , Gammaproteobacteria/genética , Metagenoma , Metagenômica , Filogenia , Salinidade , Microbiologia da Água
17.
Genome Announc ; 2(1)2014 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-24526635

RESUMO

Marine salterns are artificial multipond systems designed for the commercial production of salt by evaporation of seawater. We report here the metagenomic sequence of the prokaryotic microbiota of a pond with intermediate salinity (21% total salts) of a saltern located in Isla Cristina, Huelva, southwest Spain.

18.
Genome Announc ; 1(6)2013 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-24233589

RESUMO

Marine salterns are composed of several shallow ponds with a salinity gradient, from seawater to salt saturation, with gradually changing microbial populations. Here, we report the metagenome sequencing of the prokaryotic microbiota of two ponds with 13% and 33% salinity from a saltern in Santa Pola, Spain.

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