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1.
BMC Genomics ; 25(1): 297, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509481

RESUMO

Black flounder (Paralichthys orbignyanus, Pleuronectiformes) is a commercially significant marine fish with promising aquaculture potential in Argentina. Despite extensive studies on Black flounder aquaculture, its limited genetic information available hampers the crucial role genetics plays in the development of this activity. In this study, we first employed Illumina sequencing technology to sequence the entire genome of Black flounder. Utilizing two independent libraries-one from a female and another from a male-with 150 bp paired-end reads, a mean insert length of 350 bp, and over 35 X-fold coverage, we achieved assemblies resulting in a genome size of ~ 538 Mbp. Analysis of the assemblies revealed that more than 98% of the core genes were present, with more than 78% of them having more than 50% coverage. This indicates a somehow complete and accurate genome at the coding sequence level. This genome contains 25,231 protein-coding genes, 445 tRNAs, 3 rRNAs, and more than 1,500 non-coding RNAs of other types. Black flounder, along with pufferfishes, seahorses, pipefishes, and anabantid fish, displays a smaller genome compared to most other teleost groups. In vertebrates, the number of transposable elements (TEs) is often correlated with genome size. However, it remains unclear whether the sizes of introns and exons also play a role in determining genome size. Hence, to elucidate the potential factors contributing to this reduced genome size, we conducted a comparative genomic analysis between Black flounder and other teleost orders to determine if the small genomic size could be explained by repetitive elements or gene features, including the whole genome genes and introns sizes. We show that the smaller genome size of flounders can be attributed to several factors, including changes in the number of repetitive elements, and decreased gene size, particularly due to lower amount of very large and small introns. Thus, these components appear to be involved in the genome reduction in Black flounder. Despite these insights, the full implications and potential benefits of genome reduction in Black flounder for reproduction and aquaculture remain incompletely understood, necessitating further research.


Assuntos
Linguados , Linguado , Animais , Masculino , Feminino , Linguado/genética , Linguados/genética , Tamanho do Genoma , Mapeamento Cromossômico , Genômica
2.
Mycoses ; 67(1): e13693, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38214372

RESUMO

BACKGROUND: Damage due to respiratory viruses increases the risk of bacterial and fungal coinfections and superinfections. High rates of invasive aspergillosis are seen in severe influenza and COVID-19. This report describes CAPA cases diagnosed during the first wave in the biggest reference centre for severe COVID-19 in Mexico. OBJECTIVES: To describe the clinical, microbiological and radiological characteristics of patients with invasive pulmonary aspergillosis associated with critical COVID-19, as well as to describe the variables associated with mortality. METHODS: This retrospective study identified CAPA cases among individuals with COVID-19 and ARDS, hospitalised from 1 March 2020 to 31 March 2021. CAPA was defined according to ECMM/ISHAM consensus criteria. Prevalence was estimated. Clinical and microbiological characteristics including bacterial superinfections, antifungal susceptibility testing and outcomes were documented. RESULTS: Possible CAPA was diagnosed in 86 patients among 2080 individuals with severe COVID-19, representing 4.13% prevalence. All CAPA cases had a positive respiratory culture for Aspergillus species. Aspergillus fumigatus was the most frequent isolate (64%, n = 55/86). Seven isolates (9%, n = 7/80) were resistant to amphotericin B (A. fumigatus n = 5/55, 9%; A. niger, n = 2/7, 28%), two A. fumigatus isolates were resistant to itraconazole (3.6%, n = 2/55). Tracheal galactomannan values ranged between 1.2 and 4.05, while serum galactomannan was positive only in 11% (n = 3/26). Bacterial coinfection were documented in 46% (n = 40/86). Gram negatives were the most frequent cause (77%, n = 31/40 isolates), from which 13% (n = 4/31) were reported as multidrug-resistant bacteria. Mortality rate was 60% and worse prognosis was seen in older persons, high tracheal galactomannan index and high HbA1c level. CONCLUSIONS: One in 10 individuals with CAPA carry a resistant Aspergillus isolate and/or will be affected by a MDR bacteria. High mortality rates are seen in this population.


Assuntos
COVID-19 , Coinfecção , Aspergilose Pulmonar Invasiva , Aspergilose Pulmonar , Superinfecção , Humanos , Idoso , Idoso de 80 Anos ou mais , México/epidemiologia , Estudos Retrospectivos , COVID-19/complicações , Aspergilose Pulmonar Invasiva/complicações , Aspergilose Pulmonar Invasiva/tratamento farmacológico , Aspergilose Pulmonar Invasiva/epidemiologia , Bactérias , Hospitais
3.
Plant Sci ; 340: 111971, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38160760

RESUMO

Phospholipase C (PLC) plays a key role in lipid signaling during plant development and stress responses. PLC activation is one of the earliest responses during pathogen perception. Arabidopsis thaliana contains seven PLC encoding genes (AtPLC1 to AtPLC7) and two pseudogenes (AtPLC8 and AtPLC9), being AtPLC2 the most abundant isoform with constitutive expression in all plant organs. PLC has been linked to plant defense signaling, in particular to the production of reactive oxygen species (ROS). Previously, we demonstrated that AtPLC2 is involved in ROS production via the NADPH oxidase isoforms RBOHD activation during stomata plant immunity. Here we studied the role of AtPLC2 on plant resistance against the necrotrophic fungus Botrytis cinerea, a broad host-range and serious agricultural pathogen. We show that the AtPLC2-silenced (amiR PLC2) or null mutant (plc2-1) plants developed smaller B. cinerea lesions. Moreover, plc2-1 showed less ROS production and an intensified SA-dependent signaling upon infection, indicating that B. cinerea uses AtPLC2-triggered responses for a successful proliferation. Therefore, AtPLC2 is a susceptibility (S) gene that facilitates B. cinerea infection and proliferation.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/microbiologia , Fosfoinositídeo Fosfolipase C/genética , Fosfoinositídeo Fosfolipase C/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Botrytis/metabolismo , Fosfatidilinositóis , Proliferação de Células , Doenças das Plantas/microbiologia , Regulação da Expressão Gênica de Plantas , Oxilipinas/metabolismo , Ciclopentanos/metabolismo
4.
Cureus ; 15(8): e43869, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37736436

RESUMO

BACKGROUND: The well-recognized risk of injury to the recurrent laryngeal nerve (RLN) during thyroidectomy has instigated various preventive measures. One such measure involves directly visualizing the RLN, but this is not always feasible in practice. A more recent approach involves using intraoperative neuromonitoring to identify and preserve the RLN. This study aims to evaluate the effectiveness of intraoperative neuromonitoring compared to single visualization of the RLN in averting nerve injury. METHODS: We conducted a retrospective, observational, and descriptive study on a cohort of 218 patients. A Chi-square test was employed to determine the influence of intraoperative neuromonitoring on the incidence of nerve injury, with P < 0.05 considered statistically significant. We used Jamovi software version 2.3.18 to analyze the data. RESULTS: Of the 218 patients, intraoperative neuromonitoring was used in 150 (68.8%) cases; none of which resulted in nerve injury. Conversely, 68 (31.2%) patients underwent surgery without the use of neuromonitoring, with two (2.9%) patients in this group experiencing nerve injury (p=0.037). In comparison, the risk of nerve injury was 0% in the group monitored intraoperatively and 2.94% in the group that did not undergo intraoperatively neuromonitoring. Further, the relative risk of complications was 0.66% in patients operated with neuromonitoring, while it was 5.88% in the group operated without neuromonitoring, thus demonstrating a clinically significant protective against vasculonervous complications. CONCLUSION: The results advocate for the use of intraoperative neuromonitoring, whenever available, as it is a safe method for significantly decreasing the incidence of RLN injury during thyroidectomy compared with only visualization.

6.
Cureus ; 15(5): e38378, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37265884

RESUMO

The term ¨Lemmel Syndrome¨ is used to describe obstructive jaundice that is secondary to periampullary duodenal diverticula (PDD) in the absence of choledocholithiasis or neoplasia. PDD is found in 22% of the population. According to our knowledge, only two cases of Lemmel syndrome have been reported in Mexico. We report two cases of Lemmel syndrome in a 94-year-old and a 71-year-old woman who presented with clinical jaundice. One of the cases was treated with endoscopic retrograde cholangiopancreatography (ERCP) sphincterotomy, balloon sweep, and the placement of a plastic biliary prosthesis, and the other with laparoscopic biliodigestive bypass and a manual lateral end choledocho-duodenal anastomosis. Our objective is to expand the information on this rare pathology to take it into account as a diagnostic possibility of jaundice and to define appropriate management, which can be endoscopic or surgical.

7.
Rev Esp Enferm Dig ; 115(5): 283-284, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36719344

RESUMO

Pyogenic granuloma is a benign vascular lesion that is most frequently found in the epidermis or mucosa of the oral cavity. Its finding in the ileum is rare, there are only a few case reports. In most reported cases, diagnosis is made with capsule endoscopy or double-balloon enteroscopy. We present a case of a lesion in the ileum, approximately 15 cm from the ileocecal valve, documented by colonoscopy.


Assuntos
Granuloma Piogênico , Valva Ileocecal , Humanos , Valva Ileocecal/diagnóstico por imagem , Granuloma Piogênico/diagnóstico por imagem , Colonoscopia , Íleo/diagnóstico por imagem , Íleo/patologia , Intubação Intratraqueal
8.
Rev Esp Enferm Dig ; 115(1): 52-53, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35748465

RESUMO

Primary pancreatic lymphoma is one of the rare primary pancreatic tumors with a low incidence compared to adenocarcinoma, which is the most frequent. Currently there are diagnostic tools such as percutaneous biopsy and endoscopic ultrasound to reach its diagnosis. Primary lymphoma of the pancreas has defined therapeutic targets as well as a better prognosis compared to other tumors.


Assuntos
Adenocarcinoma , Linfoma , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/patologia , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Linfoma/diagnóstico por imagem , Pâncreas/patologia , Neoplasias Pancreáticas
9.
Rev Esp Enferm Dig ; 115(9): 527-528, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36562527

RESUMO

Multiple lymphomatous polyposis is a rare entity that can involve different types of both B-cell and T-cell lymphomas, including mantle cell lymphoma. A 57-year-old male patient is presented with prolapse of the rectal canal associated with data of lower digestive tract bleeding. A colonoscopy and subsequent upper endoscopy were performed with findings compatible with lymphomatous polyposis. After a biopsy study, mantle cell lymphoma was diagnosed and chemotherapy treatment was started. The endoscopic finding of multiple lymphomatous polypoposis associated with an adequate histopathological diagnosis improves the treatment success rate in patients with different types of gastrointestinal lymphomas.


Assuntos
Neoplasias Colorretais , Neoplasias Gastrointestinais , Linfoma de Célula do Manto , Linfoma não Hodgkin , Prolapso Retal , Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Linfoma de Célula do Manto/complicações , Linfoma de Célula do Manto/diagnóstico por imagem , Prolapso Retal/complicações , Neoplasias Gastrointestinais/complicações , Neoplasias Colorretais/complicações
12.
J Fungi (Basel) ; 8(3)2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35330219

RESUMO

Pectin is a major constituent of the plant cell wall, comprising compounds with important industrial applications such as homogalacturonan, rhamnogalacturonan and xylogalacturonan. A large array of enzymes is involved in the degradation of this amorphous substrate. The Glycoside Hydrolase 28 (GH28) family includes polygalacturonases (PG), rhamnogalacturonases (RG) and xylogalacturonases (XG) that share a structure of three to four pleated ß-sheets that form a rod with the catalytic site amidst a long, narrow groove. Although these enzymes have been studied for many years, there has been no systematic analysis. We have collected a comprehensive set of GH28 encoding sequences to study their evolution in fungi, directed at obtaining a functional classification, as well as at the identification of substrate specificity as functional constraint. Computational tools such as Alphafold, Consurf and MEME were used to identify the subfamilies' characteristics. A hierarchic classification defines the major classes of endoPG, endoRG and endoXG as well as three exoPG classes. Ascomycete endoPGs are further classified in two subclasses whereas we identify four exoRG subclasses. Diversification towards exomode is explained by loops that appear inserted in a number of turns. Substrate-driven diversification can be identified by various specificity determining positions that appear to surround the binding groove.

13.
J Fungi (Basel) ; 7(11)2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34829225

RESUMO

Histoplasmosis and pneumocystosis co-infections have been reported mainly in immunocompromised humans and in wild animals. The immunological response to each fungal infection has been described primarily using animal models; however, the host response to concomitant infection is unknown. The present work aimed to evaluate the pulmonary immunological response of patients with pneumonia caused either by Histoplasma capsulatum, Pneumocystis jirovecii, or their co-infection. We analyzed the pulmonary collectin and cytokine patterns of 131 bronchoalveolar lavage samples, which included HIV and non-HIV patients infected with H. capsulatum, P. jirovecii, or both fungi, as well as healthy volunteers and HIV patients without the studied fungal infections. Our results showed an increased production of the surfactant protein-A (SP-A) in non-HIV patients with H. capsulatum infection, contrasting with HIV patients (p < 0.05). Significant differences in median values of SP-A, IL-1ß, TNF-α, IFN-γ, IL-18, IL-17A, IL-33, IL-13, and CXCL8 were found among all the groups studied, suggesting that these cytokines play a role in the local inflammatory processes of histoplasmosis and pneumocystosis. Interestingly, non-HIV patients with co-infection and pneumocystosis alone showed lower levels of SP-A, IL-1ß, TNF-α, IFN-γ, IL-18, IL-17A, and IL-23 than histoplasmosis patients, suggesting an immunomodulatory ability of P. jirovecii over H. capsulatum response.

14.
Gac Med Mex ; 155(4): 377-385, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31486786

RESUMO

INTRODUCTION: Pneumocystis jirovecii is an atypical fungus particularly detected in HIV-positive or transplant patients. OBJECTIVE: To detect and genotype Pneumocystis jirovecii in patient samples from two hospitals in Mexico City. METHOD: Eighty-nine respiratory tract samples, corresponding to 53 patients (30 HIV-positive and 23 HIV-negative) with respiratory symptoms and to 11 healthy individuals included as negative control, were processed. DNA was extracted from the ITS region and amplified by nested polymerase chain reaction from the internal transcribed spacer, with one fragment being obtained at each round (693 and 550 bp). Genotypes and their phylogenetic relationship were determined by sequencing the 550 bp fragment. RESULTS: Forty-eight samples from 30 HIV-positive patients were received from a single hospital, out of which 11 (36.6 %) were positive for Pneumocystis jirovecii. No sample was positive in HIV-negative patients or healthy subjects. The most frequently detected haplotypes were Eg and Em. CONCLUSIONS: The frequency of Pneumocystis jirovecii infection was high in the studied Mexican population. The most common genotype was different from those reported in other countries. It is necessary to address this health problem through early detection of this infection.


INTRODUCCIÓN: Pneumocystis jirovecii es un hongo atípico detectado particularmente en pacientes VIH-positivos o con trasplante. OBJETIVO: Detectar y genotipificar Pneumocystis jirovecii en muestras de pacientes de dos hospitales de la ciudad de México. MÉTODO: Fueron procesadas 89 muestras respiratorias, correspondientes a 53 pacientes (30 VIH positivos y 23 VIH negativos) con sintomatología respiratoria y 11 personas sanas incluidas como control negativo. El DNA fue extraído y amplificado por PCR anidada de la región del espaciador transcrito interno, obteniendo un fragmento en cada ronda (de 693 y 550 pb). Los genotipos y su relación filogenética fueron determinados por secuenciación del fragmento de 550 pb. RESULTADOS: Cuarenta y ocho muestras de 30 pacientes VIH-positivos provenían de un solo hospital, de las cuales 11 (36.6 %) fueron positivas a Pneumocystis jirovecii. Ninguna fue positiva en pacientes VIH-negativos o personas sanas. Los haplotipos detectados con mayor frecuencia fueron Eg y Em. CONCLUSIONES: La frecuencia de infección por Pneumocystis jirovecii fue alta en la población mexicana estudiada. El genotipo más frecuente fue diferente a los reportados en otros países. Es necesario encauzar este problema de salud hacia la detección temprana de esta infección.


Assuntos
Infecções por HIV/complicações , Pneumocystis carinii/isolamento & purificação , Pneumonia por Pneumocystis/epidemiologia , Adulto , Idoso , Pré-Escolar , Estudos Transversais , Feminino , Genótipo , Humanos , Masculino , México , Pessoa de Meia-Idade , Filogenia , Pneumocystis carinii/genética , Pneumonia por Pneumocystis/diagnóstico , Pneumonia por Pneumocystis/microbiologia , Reação em Cadeia da Polimerase , Estudos Prospectivos , Adulto Jovem
15.
Gac. méd. Méx ; 155(4): 377-385, jul.-ago. 2019. tab, graf
Artigo em Inglês, Espanhol | LILACS | ID: biblio-1286521

RESUMO

Resumen Introducción: Pneumocystis jirovecii es un hongo atípico detectado particularmente en pacientes VIH-positivos o con trasplante. Objetivo: Detectar y genotipificar Pneumocystis jirovecii en muestras de pacientes de dos hospitales de la ciudad de México. Método: Fueron procesadas 89 muestras respiratorias, correspondientes a 53 pacientes (30 VIH positivos y 23 VIH negativos) con sintomatología respiratoria y 11 personas sanas incluidas como control negativo. El DNA fue extraído y amplificado por PCR anidada de la región del espaciador transcrito interno, obteniendo un fragmento en cada ronda (de 693 y 550 pb). Los genotipos y su relación filogenética fueron determinados por secuenciación del fragmento de 550 pb. Resultados: Cuarenta y ocho muestras de 30 pacientes VIH-positivos provenían de un solo hospital, de las cuales 11 (36.6 %) fueron positivas a Pneumocystis jirovecii. Ninguna fue positiva en pacientes VIH-negativos o personas sanas. Los haplotipos detectados con mayor frecuencia fueron Eg y Em. Conclusiones: La frecuencia de infección por Pneumocystis jirovecii fue alta en la población mexicana estudiada. El genotipo más frecuente fue diferente a los reportados en otros países. Es necesario encauzar este problema de salud hacia la detección temprana de esta infección.


Abstract Introduction: Pneumocystis jirovecii is an atypical fungus particularly detected in HIV-positive or transplant patients. Objective: To detect and genotype Pneumocystis jirovecii in patient samples from two hospitals in Mexico City. Method: Eighty-nine respiratory tract samples, corresponding to 53 patients (30 HIV-positive and 23 HIV-negative) with respiratory symptoms and to 11 healthy individuals included as negative control, were processed. DNA was extracted from the ITS region and amplified by nested polymerase chain reaction from the internal transcribed spacer, with one fragment being obtained at each round (693 and 550 bp). Genotypes and their phylogenetic relationship were determined by sequencing the 550 bp fragment. Results: Forty-eight samples from 30 HIV-positive patients were received from a single hospital, out of which 11 (36.6 %) were positive for Pneumocystis jirovecii. No sample was positive in HIV-negative patients or healthy subjects. The most frequently detected haplotypes were Eg and Em. Conclusions: The frequency of Pneumocystis jirovecii infection was high in the studied Mexican population. The most common genotype was different from those reported in other countries. It is necessary to address this health problem through early detection of this infection.


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Pneumonia por Pneumocystis/epidemiologia , Infecções por HIV/complicações , Pneumocystis carinii/isolamento & purificação , Filogenia , Pneumonia por Pneumocystis/diagnóstico , Pneumonia por Pneumocystis/microbiologia , Reação em Cadeia da Polimerase , Estudos Transversais , Estudos Prospectivos , Pneumocystis carinii/genética , Genótipo , México
16.
Int J Infect Dis ; 86: 65-72, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31207386

RESUMO

BACKGROUND: Histoplasma capsulatum and Pneumocystis jirovecii are respiratory fungal pathogens that principally cause pulmonary disease. Coinfection with both pathogens is scarcely reported. This study detected this coinfection using specific molecular methods for each fungus in the bronchoalveolar lavage (BAL) of patients from a tertiary care hospital. MATERIALS AND METHODS: BAL samples from 289 hospitalized patients were screened by PCR with specific markers for H. capsulatum (Hcp100) and P. jirovecii (mtLSUrRNA and mtSSUrRNA). The presence of these pathogens was confirmed by the generated sequences for each marker. The clinical and laboratory data for the patients were analyzed using statistical software. RESULTS: The PCR findings separated three groups of patients, where the first was represented by 60 (20.8%) histoplasmosis patients, the second by 45 (15.6%) patients with pneumocystosis, and the last group by 12 (4.2%) patients with coinfection. High similarity among the generated sequences of each species was demonstrated by BLASTn and neighbor-joining algorithms. The estimated prevalence of H. capsulatum and P. jirovecii coinfection was higher in HIV patients.


Assuntos
Coinfecção/epidemiologia , Histoplasmose/epidemiologia , Pneumocystis carinii , Pneumonia por Pneumocystis/epidemiologia , Adulto , Idoso , Lavagem Broncoalveolar , Feminino , Infecções por HIV/complicações , Histoplasma/genética , Histoplasma/isolamento & purificação , Histoplasmose/microbiologia , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Pneumocystis carinii/genética , Pneumocystis carinii/isolamento & purificação , Pneumonia por Pneumocystis/microbiologia , Reação em Cadeia da Polimerase , Centros de Atenção Terciária
17.
Biomicrofluidics ; 12(3): 034107, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29861810

RESUMO

Manual micropipettes are the most heavily used liquid handling devices in biological and chemical laboratories; however, they suffer from low precision for volumes under 1 µl and inevitable human errors. For a manual device, the human errors introduced pose potential risks of failed experiments, inaccurate results, and financial costs. Meanwhile, low precision under 1 µl can cause severe quantification errors and high heterogeneity of outcomes, becoming a bottleneck of reaction miniaturization for quantitative research in biochemical labs. Here, we report Dotette, a programmable, plug-and-play microfluidic pipetting device based on nanoliter liquid printing. With automated control, protocols designed on computers can be directly downloaded into Dotette, enabling programmable operation processes. Utilizing continuous nanoliter droplet dispensing, the precision of the volume control has been successfully improved from traditional 20%-50% to less than 5% in the range of 100 nl to 1000 nl. Such a highly automated, plug-and-play add-on to existing pipetting devices not only improves precise quantification in low-volume liquid handling and reduces chemical consumptions but also facilitates and automates a variety of biochemical and biological operations.

18.
Nat Chem Biol ; 14(1): 29-35, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29131146

RESUMO

Assembly of recombinant multiprotein systems requires multiple culturing and purification steps that scale linearly with the number of constituent proteins. This problem is particularly pronounced in the preparation of the 34 proteins involved in transcription and translation systems, which are fundamental biochemistry tools for reconstitution of cellular pathways ex vivo. Here, we engineer synthetic microbial consortia consisting of between 15 and 34 Escherichia coli strains to assemble the 34 proteins in a single culturing, lysis, and purification procedure. The expression of these proteins is controlled by synthetic genetic modules to produce the proteins at the correct ratios. We show that the pure multiprotein system is functional and reproducible, and has low protein contaminants. We also demonstrate its application in the screening of synthetic promoters and protease inhibitors. Our work establishes a novel strategy for producing pure translation machinery, which may be extended to the production of other multiprotein systems.


Assuntos
Proteínas de Escherichia coli/genética , Escherichia coli/genética , Consórcios Microbianos/genética , Engenharia de Proteínas/métodos , Proteínas Recombinantes/biossíntese , Biologia Sintética/métodos , Biossíntese de Proteínas , Proteínas Recombinantes/genética
19.
Lab Chip ; 17(13): 2198-2207, 2017 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-28613297

RESUMO

Natural genetic promoters are regulated by multiple cis and trans regulatory factors. For quantitative studies of these promoters, the concentration of only a single factor is typically varied to obtain the dose response or transfer function of the promoters with respect to the factor. Such design of experiments has limited our ability to understand quantitative, combinatorial interactions between multiple regulatory factors at promoters. This limitation is primarily due to the intractable number of experimental combinations that arise from multifactorial design of experiments. To overcome this major limitation, we integrate impact printing and cell-free systems to enable multi-dimensional studies of genetic promoters. We first present a gradient printing system which comprises parallel piezoelectric cantilever beams as a scalable actuator array to generate droplets with tunable volumes in the range of 100 pL-10 nL, which facilitates highly accurate direct dilutions in the range of 1-10 000-fold in a 1 µL drop. Next, we apply this technology to study interactions between three regulatory factors at a synthetic genetic promoter. Finally, a mathematical model of gene regulatory modules is established using the multi-parametric and multi-dimensional data. Our work creates a new frontier in the use of cell-free systems and droplet printing for multi-dimensional studies of synthetic genetic constructs.


Assuntos
Bioimpressão/instrumentação , Ensaios de Triagem em Larga Escala/instrumentação , Técnicas Analíticas Microfluídicas/instrumentação , Regiões Promotoras Genéticas/genética , Biologia Sintética/métodos , Bioimpressão/métodos , Sistema Livre de Células , DNA/química , DNA/genética , Regulação da Expressão Gênica , Ensaios de Triagem em Larga Escala/métodos , Proteínas Luminescentes/química , Técnicas Analíticas Microfluídicas/métodos , Biologia Sintética/instrumentação
20.
Plant J ; 83(5): 831-44, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26148112

RESUMO

The NADH-ubiquinone oxidoreductase complex (complex I) (EC 1.6.5.3) is the main entrance site of electrons into the respiratory chain. In a variety of eukaryotic organisms, except animals and fungi (Opisthokonta), it contains an extra domain comprising trimers of putative γ-carbonic anhydrases, named the CA domain, which has been proposed to be essential for assembly of complex I. However, its physiological role in plants is not fully understood. Here, we report that Arabidopsis mutants defective in two CA subunits show an altered photorespiratory phenotype. Mutants grown in ambient air show growth retardation compared to wild-type plants, a feature that is reversed by cultivating plants in a high-CO2 atmosphere. Moreover, under photorespiratory conditions, carbon assimilation is diminished and glycine accumulates, suggesting an imbalance with respect to photorespiration. Additionally, transcript levels of specific CA subunits are reduced in plants grown under non-photorespiratory conditions. Taken together, these results suggest that the CA domain of plant complex I contributes to sustaining efficient photosynthesis under ambient (photorespiratory) conditions.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Anidrases Carbônicas/metabolismo , Complexo I de Transporte de Elétrons/metabolismo , Proteínas de Arabidopsis/genética , Dióxido de Carbono/metabolismo , Anidrases Carbônicas/genética , Complexo I de Transporte de Elétrons/genética , Regulação da Expressão Gênica de Plantas , Glicina/metabolismo , Mutação , Oxigênio/metabolismo , Fotossíntese/genética , Folhas de Planta/genética , Folhas de Planta/fisiologia , Estrutura Terciária de Proteína , Espécies Reativas de Oxigênio/metabolismo
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