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1.
BMC Genomics ; 25(1): 614, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890559

RESUMO

BACKGROUND: To unravel the evolutionary history of a complex group, a comprehensive reconstruction of its phylogenetic relationships is crucial. This requires meticulous taxon sampling and careful consideration of multiple characters to ensure a complete and accurate reconstruction. The phylogenetic position of the Orestias genus has been estimated partly on unavailable or incomplete information. As a consequence, it was assigned to the family Cyprindontidae, relating this Andean fish to other geographically distant genera distributed in the Mediterranean, Middle East and North and Central America. In this study, using complete genome sequencing, we aim to clarify the phylogenetic position of Orestias within the Cyprinodontiformes order. RESULTS: We sequenced the genome of three Orestias species from the Andean Altiplano. Our analysis revealed that the small genome size in this genus (~ 0.7 Gb) was caused by a contraction in transposable element (TE) content, particularly in DNA elements and short interspersed nuclear elements (SINEs). Using predicted gene sequences, we generated a phylogenetic tree of Cyprinodontiformes using 902 orthologs extracted from all 32 available genomes as well as three outgroup species. We complemented this analysis with a phylogenetic reconstruction and time calibration considering 12 molecular markers (eight nuclear and four mitochondrial genes) and a stratified taxon sampling to consider 198 species of nearly all families and genera of this order. Overall, our results show that phylogenetic closeness is directly related to geographical distance. Importantly, we found that Orestias is not part of the Cyprinodontidae family, and that it is more closely related to the South American fish fauna, being the Fluviphylacidae the closest sister group. CONCLUSIONS: The evolutionary history of the Orestias genus is linked to the South American ichthyofauna and it should no longer be considered a member of the Cyprinodontidae family. Instead, we submit that Orestias belongs to the Orestiidae family, as suggested by Freyhof et al. (2017), and that it is the sister group of the Fluviphylacidae family, distributed in the Amazonian and Orinoco basins. These two groups likely diverged during the Late Eocene concomitant with hydrogeological changes in the South American landscape.


Assuntos
Ciprinodontiformes , Evolução Molecular , Genoma , Filogenia , Animais , Ciprinodontiformes/genética , Ciprinodontiformes/classificação , Elementos de DNA Transponíveis/genética , Tamanho do Genoma
2.
Proc Natl Acad Sci U S A ; 118(46)2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34725254

RESUMO

The Atacama Desert in Chile-hyperarid and with high-ultraviolet irradiance levels-is one of the harshest environments on Earth. Yet, dozens of species grow there, including Atacama-endemic plants. Herein, we establish the Talabre-Lejía transect (TLT) in the Atacama as an unparalleled natural laboratory to study plant adaptation to extreme environmental conditions. We characterized climate, soil, plant, and soil-microbe diversity at 22 sites (every 100 m of altitude) along the TLT over a 10-y period. We quantified drought, nutrient deficiencies, large diurnal temperature oscillations, and pH gradients that define three distinct vegetational belts along the altitudinal cline. We deep-sequenced transcriptomes of 32 dominant plant species spanning the major plant clades, and assessed soil microbes by metabarcoding sequencing. The top-expressed genes in the 32 Atacama species are enriched in stress responses, metabolism, and energy production. Moreover, their root-associated soils are enriched in growth-promoting bacteria, including nitrogen fixers. To identify genes associated with plant adaptation to harsh environments, we compared 32 Atacama species with the 32 closest sequenced species, comprising 70 taxa and 1,686,950 proteins. To perform phylogenomic reconstruction, we concatenated 15,972 ortholog groups into a supermatrix of 8,599,764 amino acids. Using two codon-based methods, we identified 265 candidate positively selected genes (PSGs) in the Atacama plants, 64% of which are located in Pfam domains, supporting their functional relevance. For 59/184 PSGs with an Arabidopsis ortholog, we uncovered functional evidence linking them to plant resilience. As some Atacama plants are closely related to staple crops, these candidate PSGs are a "genetic goldmine" to engineer crop resilience to face climate change.


Assuntos
Plantas/genética , Altitude , Chile , Mudança Climática , Clima Desértico , Ecossistema , Genômica/métodos , Filogenia , Solo , Microbiologia do Solo
3.
Int J Cancer ; 152(8): 1581-1592, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36451311

RESUMO

VIA is recommended for triage of HPV-positive women attending cervical screening. In the multicentric ESTAMPA study, VIA performance for detection of cervical intraepithelial neoplasia grade 3 or worse (CIN3+) among HPV-positive women was evaluated. Women aged 30-64 years were screened with HPV testing and cytology and referred to colposcopy if either test was positive. At colposcopy visit, study-trained midwives/nurses/GPs performed VIA ahead of colposcopy. VIA was considered positive if acetowhite lesions were observed in or close to the transformation zone. Ablative treatment eligibility was assessed for VIA positives. Performance indicators were estimated. Three thousand one hundred and forty-two HPV-positive women were included. Sensitivity for CIN3+ was 85.9% (95% CI 81.2-89.5) among women <50 years and, although not significant, slightly lower in women 50+ (78.0%, 95% CI 65.9-86.6). Overall specificity was 58.6% (95% CI 56.7-60.5) and was significantly higher among women 50+ (70.3%, 95% CI 66.8-73.5) compared to women <50 (54.3%, 95% CI 52.1-56.5). VIA positivity was lower among women 50+ (35.2%, 95% CI 31.9-38.6) compared to women <50 (53.2, 95% CI 51.1-55.2). Overall eligibility for ablative treatment was 74.5% and did not differ by age. VIA sensitivity, specificity, and positivity, and ablative treatment eligibility varied highly by provider (ranges: 25%-95.4%, 44.9%-94.4%, 8.2%-65.3%, 0%-98.7%, respectively). VIA sensitivity for cervical precancer detection among HPV-positive women performed by trained providers was high with an important reduction in referral rates. However, scaling-up HPV screening triaged by VIA will be challenging due to the high variability of VIA performance and providers' need for training and supervision.


Assuntos
Infecções por Papillomavirus , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Feminino , Humanos , Gravidez , Colo do Útero/patologia , Ácido Acético , Triagem , Detecção Precoce de Câncer/métodos , Programas de Rastreamento/métodos , Colposcopia
4.
Biol Res ; 56(1): 35, 2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37355658

RESUMO

BACKGROUND: High mountainous environments are of particular interest as they play an essential role for life and human societies, while being environments which are highly vulnerable to climate change and land use intensification. Despite this, our knowledge of high mountain soils in South America and their microbial community structure is strikingly scarce, which is of more concern considering the large population that depends on the ecosystem services provided by these areas. Conversely, the Central Andes, located in the Mediterranean region of Chile, has long been studied for its singular flora, whose diversity and endemism has been attributed to the particular geological history and pronounced environmental gradients in short distances. Here, we explore soil properties and microbial community structure depending on drainage class in a well-preserved Andean valley on the lower alpine vegetation belt (~2500 m a.s.l.) at 33.5˚S. This presents an opportunity to determine changes in the overall bacterial community structure across different types of soils and their distinct layers in a soil depth profile of a highly heterogeneous environment. METHODS: Five sites closely located (<1.5 km) and distributed in a well preserved Andean valley on the lower alpine vegetation belt (~2500 m a.s.l.) at 33.5˚S were selected based on a pedological approach taking into account soil types, drainage classes and horizons. We analyzed 113 soil samples using high-throughput sequencing of the 16S rRNA gene to describe bacterial abundance, taxonomic composition, and co-occurrence networks. RESULTS: Almost 18,427 Amplicon Sequence Variant (ASVs) affiliated to 55 phyla were detected. The bacterial community structure within the same horizons were very similar validating the pedological sampling approach. Bray-Curtis dissimilarity analysis revealed that the structure of bacterial communities in superficial horizons (topsoil) differed from those found in deep horizons (subsoil) in a site-specific manner. However, an overall closer relationship was observed between topsoil as opposed to between subsoil microbial communities. Alpha diversity of soil bacterial communities was higher in topsoil, which also showed more bacterial members interacting and with higher average connectivity compared to subsoils. Finally, abundances of specific taxa could be considered as biological markers in the transition from topsoil to subsoil horizons, like Fibrobacterota, Proteobacteria, Bacteroidota for shallower soils and Chloroflexi, Latescibacterota and Nitrospirota for deeper soils. CONCLUSIONS: The results indicate the importance of the soil drainage conditions for the bacterial community composition, suggesting that information of both structure and their possible ecological relationships, might be useful in clarifying the location of the edge of the topsoil-subsoil transition in mountainous environments.


Assuntos
Bactérias , Microbiota , Humanos , RNA Ribossômico 16S/genética , Bactérias/genética , Solo/química , Proteobactérias/genética , Microbiologia do Solo
5.
Biol Res ; 56(1): 6, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36797803

RESUMO

BACKGROUND: Despite representing the largest fraction of animal life, the number of insect species whose genome has been sequenced is barely in the hundreds. The order Dermaptera (the earwigs) suffers from a lack of genomic information despite its unique position as one of the basally derived insect groups and its importance in agroecosystems. As part of a national educational and outreach program in genomics, a plan was formulated to engage the participation of high school students in a genome sequencing project. Students from twelve schools across Chile were instructed to capture earwig specimens in their geographical area, to identify them and to provide material for genome sequencing to be carried out by themselves in their schools. RESULTS: The school students collected specimens from two cosmopolitan earwig species: Euborellia annulipes (Fam. Anisolabididae) and Forficula auricularia (Fam. Forficulidae). Genomic DNA was extracted and, with the help of scientific teams that traveled to the schools, was sequenced using nanopore sequencers. The sequence data obtained for both species was assembled and annotated. We obtained genome sizes of 1.18 Gb (F. auricularia) and 0.94 Gb (E. annulipes) with the number of predicted protein coding genes being 31,800 and 40,000, respectively. Our analysis showed that we were able to capture a high percentage (≥ 93%) of conserved proteins indicating genomes that are useful for comparative and functional analysis. We were also able to characterize structural elements such as repetitive sequences and non-coding RNA genes. Finally, functional categories of genes that are overrepresented in each species suggest important differences in the process underlying the formation of germ cells, and modes of reproduction between them, features that are one of the distinguishing biological properties that characterize these two distant families of Dermaptera. CONCLUSIONS: This work represents an unprecedented instance where the scientific and lay community have come together to collaborate in a genome sequencing project. The versatility and accessibility of nanopore sequencers was key to the success of the initiative. We were able to obtain full genome sequences of two important and widely distributed species of insects which had not been analyzed at this level previously. The data made available by the project should illuminate future studies on the Dermaptera.


Assuntos
Insetos , Animais , Insetos/genética , Análise de Sequência de DNA , Chile
6.
Genomics ; 114(1): 305-315, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34954349

RESUMO

Orestias ascotanensis (Cyprinodontidae) is a teleost pupfish endemic to springs feeding into the Ascotan saltpan in the Chilean Altiplano (3,700 m.a.s.l.) and represents an opportunity to study adaptations to high-altitude aquatic environments. We have de novo assembled the genome of O. ascotanensis at high coverage. Comparative analysis of the O. ascotanensis genome showed an overall process of contraction, including loss of genes related to G-protein signaling, chemotaxis and signal transduction, while there was expansion of gene families associated with microtubule-based movement and protein ubiquitination. We identified 818 genes under positive selection, many of which are involved in DNA repair. Additionally, we identified novel and conserved microRNAs expressed in O. ascotanensis and its closely-related species, Orestias gloriae. Our analysis suggests that positive selection and expansion of genes that preserve genome stability are a potential adaptive mechanism to cope with the increased solar UV radiation to which high-altitude animals are exposed to.


Assuntos
Fundulidae , Peixes Listrados , Adaptação Fisiológica/genética , Altitude , Animais , Fundulidae/genética , Peixes Listrados/genética , Filogenia , Transcriptoma
7.
Sensors (Basel) ; 23(12)2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37420605

RESUMO

Wearable devices are starting to gain popularity, which means that a large portion of the population is starting to acquire these products. This kind of technology comes with a lot of advantages, as it simplifies different tasks people do daily. However, as they recollect sensitive data, they are starting to be targets for cybercriminals. The number of attacks on wearable devices forces manufacturers to improve the security of these devices to protect them. Many vulnerabilities have appeared in communication protocols, specifically Bluetooth. We focus on understanding the Bluetooth protocol and what countermeasures have been applied during their updated versions to solve the most common security problems. We have performed a passive attack on six different smartwatches to discover their vulnerabilities during the pairing process. Furthermore, we have developed a proposal of requirements needed for maximum security of wearable devices, as well as the minimum requirements needed to have a secure pairing process between two devices via Bluetooth.


Assuntos
Dispositivos Eletrônicos Vestíveis , Humanos , Segurança Computacional , Comunicação
8.
Int J Mol Sci ; 24(19)2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37834314

RESUMO

Lactose intolerance (LI) and vitamin D deficiency (VDD) have been linked to inflammatory bowel disease (IBD). We conducted an observational study in 192 Chilean IBD patients to investigate the prevalence of a specific gene variant (LCT-13910 CC genotype) associated with LI and the prevalence of VDD/Vitamin D Receptor (VDR) gene variants. Blood samples were analyzed using Illumina's Infinium Global Screening Array. The LCT-13910 CC genotype was found in 61% of IBD patients, similar to Chilean Hispanic controls and lower than Chilean Amerindian controls. The frequency of the LCT-13910-C allele in Chilean IBD patients (0.79) was comparable to the general population and higher than Europeans (0.49). Regarding VDR and VDD variants, in our study, the rs12785878-GG variant was associated with an increased risk of IBD (OR = 2.64, CI = 1.61-4.32; p-value = 0.001). Sixty-one percent of the Chilean IBD cohort have a genetic predisposition to lactose malabsorption, and a significant proportion exhibit genetic variants associated with VDD/VDR. Screening for LI and VDD is crucial in this Latin American IBD population.


Assuntos
Doenças Inflamatórias Intestinais , Lactose , Receptores de Calcitriol , Humanos , Chile/epidemiologia , Predisposição Genética para Doença , Genótipo , Doenças Inflamatórias Intestinais/epidemiologia , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/complicações , Lactose/deficiência , Polimorfismo de Nucleotídeo Único , Prevalência , Receptores de Calcitriol/genética , Vitamina D , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/epidemiologia , Deficiência de Vitamina D/genética
9.
New Phytol ; 234(6): 2126-2139, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35274744

RESUMO

The discovery and characterization of plant species adapted to extreme environmental conditions have become increasingly important. Hoffmannseggia doellii is a perennial herb endemic to the Chilean Atacama Desert that grows in the western Andes between 2800 and 3600 m above sea level. Its growing habitat is characterized by high radiation and low water and nutrient availability. Under these conditions, H. doellii can grow, reproduce, and develop an edible tuberous root. We characterized the H. doellii soil-associated microbiomes to understand the biotic factors that could influence their surprising ability to survive. We found an increased number of observed species and higher phylogenetic diversity of bacteria and fungi on H. doellii root soils compared with bare soil (BS) along different sites and to soil microbiomes of other plant species. Also, the H. doellii-associated microbiome had a higher incidence of overall positive interactions and fungal within-kingdom interactions than their corresponding BS network. These findings suggest a microbial diversity soil modulation mechanism that may be a characteristic of highly tolerant plants to diverse and extreme environments. Furthermore, since H. doellii is related to important cultivated crops, our results create an opportunity for future studies on climate change adaptation of crop plants.


Assuntos
Microbiota , Microbiologia do Solo , Clima Desértico , Filogenia , Plantas , Solo
10.
Am J Respir Crit Care Med ; 204(1): 34-43, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33823118

RESUMO

Rationale: The role of and needs for extracorporeal membrane oxygenation (ECMO) at a population level during the coronavirus disease (COVID-19) pandemic have not been completely established. Objectives: To identify the cumulative incidence of ECMO use in the first pandemic wave and to describe the Nationwide Chilean cohort of ECMO-supported patients with COVID-19. Methods: We conducted a population-based study from March 3 to August 31, 2020, using linked data from national agencies. The cumulative incidence of ECMO use and mortality risk of ECMO-supported patients were calculated and age standardized. In addition, a retrospective cohort analysis was performed. Outcomes were 90-day mortality after ECMO initiation, ECMO-associated complications, and hospital length of stay. Cox regression models were used to explore risk factors for mortality in a time-to-event analysis. Measurements and Main Results: Ninety-four patients with COVID-19 were supported with ECMO (0.42 per population of 100,000, 14.89 per 100,000 positive cases, and 1.2% of intubated patients with COVID-19); 85 were included in the cohort analysis, and the median age was 48 (interquartile range [IQR], 41-55) years, 83.5% were men, and 42.4% had obesity. The median number of pre-ECMO intubation days was 4 (IQR, 2-7), the median PaO2/FiO2 ratio was 86.8 (IQR, 64-99) mm Hg, 91.8% of patients were prone positioned, and 14 patients had refractory respiratory acidosis. Main complications were infections (70.6%), bleeding (38.8%), and thromboembolism (22.4%); 52 patients were discharged home, and 33 died. The hospital length of stay was a median of 50 (IQR, 24-69) days. Lower respiratory system compliance and higher driving pressure before ECMO initiation were associated with increased mortality. A duration of pre-ECMO intubation ≥10 days was not associated with mortality. Conclusions: Documenting nationwide ECMO needs may help in planning ECMO provision for future COVID-19 pandemic waves. The 90-day mortality of the Chilean cohort of ECMO-supported patients with COVID-19 (38.8%) is comparable to that of previous reports.


Assuntos
COVID-19/terapia , Oxigenação por Membrana Extracorpórea/estatística & dados numéricos , Síndrome do Desconforto Respiratório/terapia , Adulto , Idoso , COVID-19/complicações , COVID-19/diagnóstico , COVID-19/epidemiologia , Chile/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Avaliação das Necessidades , Síndrome do Desconforto Respiratório/diagnóstico , Síndrome do Desconforto Respiratório/epidemiologia , Síndrome do Desconforto Respiratório/virologia , Estudos Retrospectivos , Índice de Gravidade de Doença , Resultado do Tratamento
11.
J Exp Bot ; 72(7): 2525-2543, 2021 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-33367755

RESUMO

Sucrose metabolism is important for most plants, both as the main source of carbon and via signaling mechanisms that have been proposed for this molecule. A cleaving enzyme, invertase (INV) channels sucrose into sink metabolism. Although acid soluble and insoluble invertases have been largely investigated, studies on the role of neutral invertases (A/N-INV) have lagged behind. Here, we identified a tomato A/N-INV encoding gene (NI6) co-localizing with a previously reported quantitative trait locus (QTL) largely affecting primary carbon metabolism in tomato. Of the eight A/N-INV genes identified in the tomato genome, NI6 mRNA is present in all organs, but its expression was higher in sink tissues (mainly roots and fruits). A NI6-GFP fusion protein localized to the cytosol of mesophyll cells. Tomato NI6-silenced plants showed impaired growth phenotype, delayed flowering and a dramatic reduction in fruit set. Global gene expression and metabolite profile analyses of these plants revealed that NI6 is not only essential for sugar metabolism, but also plays a signaling role in stress adaptation. We also identified major hubs, whose expression patterns were greatly affected by NI6 silencing; these hubs were within the signaling cascade that coordinates carbohydrate metabolism with growth and development in tomato.


Assuntos
Frutas/fisiologia , Solanum lycopersicum , beta-Frutofuranosidase , Citosol , Solanum lycopersicum/enzimologia , Solanum lycopersicum/genética , Sacarose , beta-Frutofuranosidase/genética
12.
Prev Med ; 153: 106801, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34508733

RESUMO

WHO cervical cancer elimination goals comprise 70% of highly-sensitive screening coverage and 90% treatment of precancerous lesions. Triage for HPV-positive women may challenge sensitivity of screening algorithms and women's follow-up, particularly in low- and middle-income countries (LMIC) where screening quality and protocol adherence are frequently deficient. We aimed to determine the accuracy of triage for HPV positive women in routine screening services from Colombia by a prospective cross-sectional study. Consecutively, HPV DNA-positive women underwent six triage strategies (conventional cytology, two methods of visual inspection, HPV16/18/45-genotyping, telomerase, and HPV mRNA). Positive triage results underwent regular colposcopy/biopsy in public hospitals. Adjusted sensitivity, specificity, and predictive values for CIN2+/CIN3+ were estimated for stand-alone and combined tests. We explored the impact of triage strategies on referral rates and the complete screening algorithm (screening plus triage). Overall 16,242 women underwent HPV screening and 1789 (11.0%) were HPV-positive. In total, 20.1% of women were lost to follow-up. mRNA showed the highest positivity rate (0.64 among HPV-positive and 0.05 among the total screened cohort), the highest sensitivity (0.94 95%CI 0.75-0.96), and the lowest specificity (0.36 95%CI 0.29-0.43). Parallel testing with HPV-mRNA revealed the highest increase in sensitivity for all triage strategies. Accuracy of cytology and visual inspection differ between screening units but parallel testing with HPV16/18/45 genotyping significantly increased their sensitivity (over 0.80). Morphology-based triage for HPV-positive women remains a suitable alternative for routine practice in LMIC if combined with HPV16/18/45-genotyping; however, point-of-care triage would be preferable to reduce losses to follow-up. HPV-mRNA triage deserves cost-benefit analyses.


Assuntos
Infecções por Papillomavirus , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Colômbia , Colposcopia , Estudos Transversais , Detecção Precoce de Câncer/métodos , Feminino , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Humanos , Programas de Rastreamento/métodos , Infecções por Papillomavirus/patologia , Gravidez , Estudos Prospectivos , Triagem , Esfregaço Vaginal/métodos , Displasia do Colo do Útero/patologia
13.
J Intensive Care Med ; 35(9): 927-932, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32677498

RESUMO

The coronavirus disease 2019 pandemic resulted in unprecedented numbers of patients with respiratory failure requiring ventilatory support. The number of patients who required critical care quickly outpaced the availability of intensive care unit (ICU) beds. Consequently, health care systems had to creatively expand critical care services into alternative hospital locations with repurposed staff and equipment. Deploying anesthesia workstations to the ICU to serve as mechanical ventilators requires equipment preparation, multidisciplinary planning, and targeted education. We aim to contextualize this process, highlighting major differences between anesthesia workstations and ICU ventilators, and to share the insights gained from our experiences creating an anesthesia provider-based ventilator management team.


Assuntos
Anestesia Geral/instrumentação , Infecções por Coronavirus/terapia , Unidades de Terapia Intensiva/organização & administração , Equipe de Assistência ao Paciente/organização & administração , Pneumonia Viral/terapia , Respiração Artificial/instrumentação , Ventiladores Mecânicos/provisão & distribuição , Betacoronavirus , COVID-19 , Humanos , Pandemias , SARS-CoV-2
14.
Biol Res ; 53(1): 29, 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32631429

RESUMO

Arid environments are defined by the lack of water availability, which is directly related to the mean annual precipitation (MAP), and high values of solar irradiation, which impacts the community composition of animals, plants, and the microbial structure of the soil. Recent advances in NGS technologies have expanded our ability to characterize microbiomes, allowing environmental microbiologists to explore the complete microbial structure. Intending to identify and describe the state-of-the-art of bacterial communities in arid soils at a global scale, and to address the effect that some environmental features may have on them, we performed a systematic review based on the PRISMA guideline. Using a combination of keywords, we identified a collection of 66 studies, including 327 sampled sites, reporting the arid soil bacterial community composition by 16S rDNA gene high-throughput sequencing. To identify factors that can modulate bacterial communities, we extracted the geographical, environmental, and physicochemical data. The results indicate that even though each sampled site was catalogued as arid, they show wide variability in altitude, mean annual temperature (MAT), soil pH and electric conductivity, within and between arid environments. We show that arid soils display a higher abundance of Actinobacteria and lower abundance of Proteobacteria, Cyanobacteria, and Planctomycetes, compared with non-arid soil microbiomes, revealing that microbial structure seems to be strongly modulated by MAP and MAT and not by pH in arid soils. We observed that environmental and physicochemical features were scarcely described among studies, hence, we propose a reporting guideline for further analysis, which will allow deepening the knowledge of the relationship between the microbiome and abiotic factors in arid soil. Finally, to understand the academic collaborations landscape, we developed an analysis of the author's network, corroborating a low degree of connectivity and collaborations in this research topic. Considering that it is crucial to understand how microbial processes develop and change in arid soils, our analysis emphasizes the need to increase collaborations between research groups worldwide.


Assuntos
Microbiota , Microbiologia do Solo , Animais , Microbiota/genética , Plantas , Proteobactérias , Solo
15.
Mar Drugs ; 18(5)2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32414006

RESUMO

Pesticides cause severe environmental damage to marine ecosystems. In the last ten years, cypermethrin has been extensively used as an antiparasitic pesticide in the salmon farming industry located in Northern Patagonia. The objective of this study was the biochemical and genomic characterization of cypermethrin-degrading and biosurfactant-producing bacterial strains isolated from cypermethrin-contaminated marine sediment samples collected in southern Chile (MS). Eleven strains were isolated by cypermethrin enrichment culture techniques and were identified by 16S rDNA gene sequencing analyses. The highest growth rate on cypermethrin was observed in four isolates (MS13, MS15a, MS16, and MS19) that also exhibited high levels of biosurfactant production. Genome sequence analyses of these isolates revealed the presence of genes encoding components of bacterial secondary metabolism, and the enzymes esterase, pyrethroid hydrolase, and laccase, which have been associated with different biodegradation pathways of cypermethrin. These novel cypermethrin-degrading and biosurfactant-producing bacterial isolates have a biotechnological potential for biodegradation of cypermethrin-contaminated marine sediments, and their genomes contribute to the understanding of microbial lifestyles in these extreme environments.


Assuntos
Bactérias/metabolismo , Sedimentos Geológicos/microbiologia , Praguicidas/metabolismo , Piretrinas/metabolismo , Microbiologia do Solo , Bactérias/genética , Biodegradação Ambiental , Chile , Humanos , Oceanos e Mares , Filogenia , Tensoativos/metabolismo
16.
Anesth Analg ; 139(1): e4-e5, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38885402
17.
Plant Cell Physiol ; 59(11): 2188-2203, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30239816

RESUMO

Tocopherols are non-polar compounds synthesized in the plastids, which function as major antioxidants of the plant cells and are essential in the human diet. Both the intermediates and final products of the tocopherol biosynthetic pathway must cross plastid membranes to reach their sites of action. So far, no protein with tocopherol binding activity has been reported in plants. Here, we demonstrated that the tomato SlTBP protein is targeted to chloroplasts and able to bind α-tocopherol. SlTBP-knockdown tomato plants exhibited reduced levels of tocopherol in both leaves and fruits. Several tocopherol deficiency phenotypes were apparent in the transgenic lines, such as alterations in photosynthetic parameters, dramatic distortion of thylakoid membranes and significant variations in the lipid profile. These results, along with the altered expression of genes related to photosynthesis, and tetrapyrrole, lipid, isoprenoid, inositol/phosphoinositide and redox metabolism, suggest that SlTBP may act in conducting tocopherol (or its biosynthetic intermediates) between the plastid compartments and/or at the interface between chloroplast and endoplasmic reticulum membranes, affecting interorganellar lipid metabolism.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas de Plantas/metabolismo , Solanum lycopersicum/metabolismo , alfa-Tocoferol/metabolismo , Cloroplastos/metabolismo , Retículo Endoplasmático/metabolismo , Técnicas de Silenciamento de Genes , Metabolismo dos Lipídeos , Solanum lycopersicum/genética , Filogenia , Proteínas de Plantas/genética , Plastídeos/metabolismo
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