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1.
J Fungi (Basel) ; 10(4)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38667906

RESUMO

Green mold caused by Penicillium digitatum (Pers.:Fr.) Sacc is the most prevalent postharvest rot concerning citrus fruits. Using the subtractive suppression hybridization (SSH) technique, different P. digitatum genes have been identified that could be involved in virulence during citrus infection in the early stages, a crucial moment that determines whether the infection progresses or not. To this end, a comparison of two P. digitatum strains with high and low virulence has been carried out. We conducted a study on the gene expression profile of the most relevant genes. The results indicate the importance of transcription and regulation processes as well as enzymes involved in the degradation of the plant cell wall. The most represented expressed sequence tag (EST) was identified as PDIP_11000, associated with the FluG domain, which is putatively involved in the activation of conidiation. It is also worth noting that PDIP_02280 encodes a pectin methyl esterase, a cell wall remodeling protein with a high expression level in the most virulent fungal strains, which is notably induced during citrus infection. Furthermore, within the group with the greatest representation and showing significant induction in the early stages of infection, regulatory proteins (PDIP_68700, PDIP_76160) and a chaperone (PDIP_38040) stand out. To a lesser extent, but not less relevant, it is worth distinguishing different regulatory proteins and transcription factors, such as PDIP_00580, PDIP_49640 and PDIP_78930.

2.
Heliyon ; 10(7): e29124, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38623190

RESUMO

Pathogenesis of P. expansum involved different processes and one of them is the recognition between pathogen-host, which in the case of P. expansum is preferably pome fruit. In this work, the possible mechanisms connected to host recognition are addressed through the generation of a subtractive library carried out during the incompatible P. expansum-orange interaction in the initial stages of infection. The generated library was analyzed by massive sequencing and bioinformatic analysis. Of the identified genes, a total of 24 were selected for subsequent expression analysis by RT-qPCR in two incompatible interaction situations. The characterization of the overexpressed genes revealed the presence of CWDEs, ATPases, aldolases, detoxifying enzymes and virulent determinants that could act as effectors related to fungal virulence independently of the host. However, several identified genes, which could not be associated with the virulence of P. expansum under compatible conditions, were related to enzymes to obtain the nutrients necessary for the growth and development of the pathogen under stress conditions through basal metabolism that contributes to expand the range of adaptation of the pathogen to the environment and different hosts.

3.
Int J Food Microbiol ; 413: 110579, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38277871

RESUMO

Plant extracts are used as an alternative to a wide range of foods against different types of fungal pathogens. In the present study, the extracts of avocado leaves (Persea americana) and majagua flowers (Talipariti elatum) were tested according to their antifungal activity against different fungi. The most promising extracts were those of majagua flowers that were applied lyophilized and in aqueous extract, being very effective against Alternaria alternata and reaching a 50 % in vitro reduction. Antifungal properties were also evaluated during infection of apples by A. alternata. A decrease in infection progression was confirmed with up to a 30 % reduction in disease incidence and a 20 % reduction in disease severity. Majagua extracts were also tested combined with edible pectin coatings, greatly increasing their effectiveness up 60 % reduction. Thus, extracts of majagua could provide a feasible alternative to control fungal pathogens during postharvest.


Assuntos
Antifúngicos , Persea , Antifúngicos/farmacologia , Alternaria , Pectinas , Extratos Vegetais/farmacologia , Flores
4.
BMC Med Inform Decis Mak ; 24(1): 28, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38291389

RESUMO

BACKGROUND: Nutritional risk situations related to decreased food intake in the hospital environment hinder nutritional care and increase malnutrition in hospitalized patients and are often associated with increased morbidity and mortality. The objective of this study is to develop and test the reliability and data similarity of a mobile application as a virtual instrument to assess the acceptability and quality of hospital diets for inpatients. METHODS: This intra- and interobserver development and reliability study investigated an in-hospital food intake monitoring application based on a validated instrument for patients with infectious diseases who were treated at the Evandro Chagas National Institute of Infectious Diseases (INI/FIOCRUZ). The instrument was sequentially administered to patients 48 h after admission to INI hospital units using the printed instrument (paper) and the digital application (ARIETI) simultaneously. The tested reliability factor was the consistency of the method in the digital platform, checking whether the application provided equivalent data to the paper instrument, and finally, a statistical analysis plan was performed in the R platform version 4.2.0. This project was authorized by the FIOCRUZ/INI Research Ethics Committee. RESULTS: The ARIETI was developed and tested for reliability in 70 participants, showing a similar ability to calculate caloric intake in Kcal, protein intake (g), the proportion of caloric intake and protein intake relative to the prescribed goal. These instrument comparison analyses showed statistical significance (p < 0.001). The application was superior to the paper-based instrument, accelerating the time to perform the nutritional risk diagnosis based on food intake by approximately 250 s (average time). CONCLUSIONS: The ARIETI application has demonstrated equivalent reliability compared to the original instrument. Moreover, it optimized the time between the diagnosis of nutritional risk related to dietary intake and the nutritionist's decision making, showing an improved ability to maintain information quality compared to the paper-based instrument.


Assuntos
Doenças Transmissíveis , Aplicativos Móveis , Humanos , Pacientes Internados , Reprodutibilidade dos Testes , Dieta , Ingestão de Alimentos
5.
EMBO J ; 43(3): 462-480, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38216735

RESUMO

Kinases that synthesize inositol phosphates (IPs) and pyrophosphates (PP-IPs) control numerous biological processes in eukaryotic cells. Herein, we extend this cellular signaling repertoire to viruses. We have biochemically and structurally characterized a minimalist inositol phosphate kinase (i.e., TvIPK) encoded by Terrestrivirus, a nucleocytoplasmic large ("giant") DNA virus (NCLDV). We show that TvIPK can synthesize inositol pyrophosphates from a range of scyllo- and myo-IPs, both in vitro and when expressed in yeast cells. We present multiple crystal structures of enzyme/substrate/nucleotide complexes with individual resolutions from 1.95 to 2.6 Å. We find a heart-shaped ligand binding pocket comprising an array of positively charged and flexible side chains, underlying the observed substrate diversity. A crucial arginine residue in a conserved "G-loop" orients the γ-phosphate of ATP to allow substrate pyrophosphorylation. We highlight additional conserved catalytic and architectural features in TvIPK, and support their importance through site-directed mutagenesis. We propose that NCLDV inositol phosphate kinases may have assisted evolution of inositol pyrophosphate signaling, and we discuss the potential biogeochemical significance of TvIPK in soil niches.


Assuntos
Difosfatos , Vírus Gigantes , Difosfatos/metabolismo , Vírus Gigantes/metabolismo , Fosfatos de Inositol/química , Fosfatos de Inositol/metabolismo , Fosfatos/metabolismo , Saccharomyces cerevisiae/metabolismo
6.
Encephale ; 50(1): 85-90, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37993287

RESUMO

While most adults confronted with the death of a loved one manage to grieve, about 10-20% of individuals develop complicated grief, characterized by persistent distress and impaired social skills, or pathological grief, defined by the onset or decompensation of a psychiatric disorder. Little is known about the biological causes of these grief complications. Recent work suggests that oxytocin, a major neuroendocrine hormone regulating many neurocognitive mechanisms, may be involved in this process. Oxytocin is widely studied and well known for its impact on the mother-child bond and hormonal and brain systems related to attachment and social interactions. In this article, we propose a neurocognitive model of grief complications based on existing data on the role of oxytocin in interpersonal attachment and its impact on brain activity. We suggest that complicated grief is associated with dysfunctional cerebral oxytocinergic signaling and persistent hyperactivation of the nucleus accumbens. This mechanism is involved in limiting the reduction of interpersonal attachment to the deceased during acute phases and in searching for new interpersonal relationships during the recovery phase. We show how the exploration of cerebral oxytocinergic signaling would improve the understanding of physiological grief mechanisms in the general population and could allow the development of new therapeutic perspectives against the complications of grief.


Assuntos
Amor , Ocitocina , Adulto , Humanos , Ocitocina/uso terapêutico , Pesar , Encéfalo , Dor
7.
Hum Mol Genet ; 33(5): 400-425, 2024 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-37947217

RESUMO

Spinal muscular atrophy (SMA) is a genetic neuromuscular disorder caused by the reduction of survival of motor neuron (SMN) protein levels. Although three SMN-augmentation therapies are clinically approved that significantly slow down disease progression, they are unfortunately not cures. Thus, complementary SMN-independent therapies that can target key SMA pathologies and that can support the clinically approved SMN-dependent drugs are the forefront of therapeutic development. We have previously demonstrated that prednisolone, a synthetic glucocorticoid (GC) improved muscle health and survival in severe Smn-/-;SMN2 and intermediate Smn2B/- SMA mice. However, long-term administration of prednisolone can promote myopathy. We thus wanted to identify genes and pathways targeted by prednisolone in skeletal muscle to discover clinically approved drugs that are predicted to emulate prednisolone's activities. Using an RNA-sequencing, bioinformatics, and drug repositioning pipeline on skeletal muscle from symptomatic prednisolone-treated and untreated Smn-/-; SMN2 SMA and Smn+/-; SMN2 healthy mice, we identified molecular targets linked to prednisolone's ameliorative effects and a list of 580 drug candidates with similar predicted activities. Two of these candidates, metformin and oxandrolone, were further investigated in SMA cellular and animal models, which highlighted that these compounds do not have the same ameliorative effects on SMA phenotypes as prednisolone; however, a number of other important drug targets remain. Overall, our work further supports the usefulness of prednisolone's potential as a second-generation therapy for SMA, identifies a list of potential SMA drug treatments and highlights improvements for future transcriptomic-based drug repositioning studies in SMA.


Assuntos
Reposicionamento de Medicamentos , Atrofia Muscular Espinal , Camundongos , Animais , Preparações Farmacêuticas , Atrofia Muscular Espinal/tratamento farmacológico , Atrofia Muscular Espinal/genética , Atrofia Muscular Espinal/metabolismo , Músculo Esquelético/metabolismo , Perfilação da Expressão Gênica , Prednisolona/uso terapêutico , Modelos Animais de Doenças , Proteína 1 de Sobrevivência do Neurônio Motor/genética , Proteína 1 de Sobrevivência do Neurônio Motor/metabolismo
8.
Life Sci Alliance ; 6(4)2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36732018

RESUMO

The initial dissemination of cancer cells from many primary tumors implies intravasation to lymphatic nodes or blood vessels. To investigate the mechanisms involved, we analyzed the expression of small non-coding RNAs in cutaneous squamous cell carcinoma (cSCC), a prevalent tumor that mainly spreads to lymph nodes. We report the reduced expression of small nucleolar RNAs in primary cSCCs that metastasized when compared to non-metastasizing cSCCs, and the progressive loss of DKC1 (dyskerin, which stabilizes the small nucleolar RNAs) along the metastasis. DKC1 depletion in cSCC cells triggered lipid metabolism by altering the mevalonate pathway and the acquisition of metastatic traits. Treatment of DKC1-depleted cells with simvastatin, an inhibitor of the mevalonate pathway, blocked the expression of proteins involved in the epithelial-to-mesenchymal transition. Consistently, the expression of the enzyme 3-hydroxy-3-methylglutaryl-CoA synthase 1 was associated with pathological features of high metastatic risk in cSCC patients. Our data underpin the relevance of the mevalonate metabolism in metastatic dissemination and pave the possible incorporation of therapeutic approaches among the antineoplastic drugs used in routine patient care.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Cutâneas , Humanos , Carcinoma de Células Escamosas/metabolismo , Neoplasias Cutâneas/patologia , Ácido Mevalônico , Fenótipo , Sinvastatina/farmacologia , Proteínas Nucleares , Proteínas de Ciclo Celular
9.
J Fungi (Basel) ; 8(9)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36135672

RESUMO

Postharvest diseases cause high economic losses in the global citrus and pome fruit industry [...].

10.
Adv Biol Regul ; 83: 100835, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34782304

RESUMO

Initial studies on the inositol phosphates metabolism were enabled by the social amoeba Dictyostelium discoideum. The abundant amount of inositol hexakisphosphate (IP6 also known as Phytic acid) present in the amoeba allowed the discovery of the more polar inositol pyrophosphates, IP7 and IP8, possessing one or two high energy phosphoanhydride bonds, respectively. Considering the contemporary growing interest in inositol pyrophosphates, it is surprising that in recent years D. discoideum, has contributed little to our understanding of their metabolism and function. This work fulfils this lacuna, by analysing the ip6k, ppip5k and ip6k-ppip5K amoeba null strains using PAGE, 13C-NMR and CE-MS analysis. Our study reveals an inositol pyrophosphate metabolism more complex than previously thought. The amoeba Ip6k synthesizes the 4/6-IP7 in contrast to the 5-IP7 isomer synthesized by the mammalian homologue. The amoeba Ppip5k synthesizes the same 1/3-IP7 as the mammalian enzyme. In D. discoideum, the ip6k strain possesses residual amounts of IP7. The residual IP7 is also present in the ip6k-ppip5K strain, while the ppip5k single mutant shows a decrease in both IP7 and IP8 levels. This phenotype is in contrast to the increase in IP7 observable in the yeast vip1Δ strain. The presence of IP8 in ppip5k and the presence of IP7 in ip6k-ppip5K indicate the existence of an additional inositol pyrophosphate synthesizing enzyme. Additionally, we investigated the existence of a metabolic relationship between inositol pyrophosphate synthesis and inorganic polyphosphate (polyP) metabolism as observed in yeast. These studies reveal that contrary to the yeast, Ip6k and Ppip5k do not control polyP cellular level in amoeba.


Assuntos
Dictyostelium , Animais , Dictyostelium/genética , Dictyostelium/metabolismo , Difosfatos/metabolismo , Humanos , Fosfatos de Inositol/metabolismo , Mamíferos/metabolismo , Fosfotransferases (Aceptor do Grupo Fosfato)/genética , Fosfotransferases (Aceptor do Grupo Fosfato)/metabolismo , Polifosfatos/metabolismo
11.
J Fungi (Basel) ; 7(10)2021 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-34682249

RESUMO

Zn2Cys6 transcription factors are unique to fungi and are involved in different regulatory functions. In this study, we have identified the Penicillium digitatumPdMut3 gene, which encodes a putative Zn (II) 2Cys6 DNA-binding protein. Elimination of PdMut3 in Pd1 strain caused increased virulence during citrus infection. The transcription of the PdMut3 gene showed a higher expression rate during fungal growth and less transcription during fruit infection. Furthermore, the deletion of the gene in the wild-type isolate of P. digitatum did not produce any modification of the sensitivity to different fungicides, indicating that the gene is not associated with resistance to fungicides. In contrast, PdMut3 null mutants showed a reduction in growth in minimal media, which was associated with severe alterations in conidiophore development and morphological alterations of the hyphae. Mutants showed greater sensitivity to compounds that interfere with the cell wall and an invasive growth block. Thus, PdMut3 might have an indirect role in fungi virulence through metabolism and peroxisomes development.

12.
J Fungi (Basel) ; 7(9)2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34575821

RESUMO

The necrotrophic fungus Penicillium digitatum (Pd) is responsible for the green mold disease that occurs during postharvest of citrus and causes enormous economic losses around the world. Fungicides remain the main method used to control postharvest green mold in citrus fruit storage despite numerous occurrences of resistance to them. Hence, it is necessary to find new and more effective strategies to control this type of disease. This involves delving into the molecular mechanisms underlying the appearance of resistance to fungicides during the plant-pathogen interaction. Although mechanisms involved in resistance to fungicides have been studied for many years, there have now been great advances in the molecular aspects that drive fungicide resistance, which facilitates the design of new means to control green mold. A wide review allows the mechanisms underlying fungicide resistance in Pd to be unveiled, taking into account not only the chemical nature of the compounds and their target of action but also the general mechanism that could contribute to resistance to others compounds to generate what we call multidrug resistance (MDR) phenotypes. In this context, fungal transporters seem to play a relevant role, and their mode of action may be controlled along with other processes of interest, such as oxidative stress and fungal pathogenicity. Thus, the mechanisms for acquisition of resistance to fungicides seem to be part of a complex framework involving aspects of response to stress and processes of fungal virulence.

13.
Comput Struct Biotechnol J ; 19: 2676-2686, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093984

RESUMO

Endoxylanases active under extreme conditions of temperature and alkalinity can replace the use of highly pollutant chemicals in the pulp and paper industry. Searching for enzymes with these properties, we carried out a comprehensive bioinformatics study of the GH10 family. The phylogenetic analysis allowed the construction of a radial cladogram in which protein sequences putatively ascribed as thermophilic and alkaliphilic appeared grouped in a well-defined region of the cladogram, designated TAK Cluster. One among five TAK sequences selected for experimental analysis (Xyn11) showed extraordinary xylanolytic activity under simultaneous conditions of high temperature (90 °C) and alkalinity (pH 10.5). Addition of a carbohydrate binding domain (CBM2) at the C-terminus of the protein sequence further improved the activity of the enzyme at high pH. Xyn11 structure, which has been solved at 1.8 Å resolution by X-ray crystallography, reveals an unusually high number of hydrophobic, ionic and hydrogen bond atomic interactions that could account for the enzyme's extremophilic nature.

14.
Adv Biol Regul ; 79: 100782, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33422459

RESUMO

Inositol phosphate encompasses a large multifaceted family of signalling molecules that originate from the combinatorial attachment of phosphate groups to the inositol ring. To date, four distinct inositol kinases have been identified, namely, IPK, ITPK, IPPK (IP5-2K), and PPIP5K. Although, ITPKs have recently been identified in archaea, eukaryotes have taken advantage of these enzymes to create a sophisticated signalling network based on inositol phosphates. However, it remains largely elusive what fundamental biochemical principles control the signalling cascade. Here, we present an evolutionary approach to understand the development of the 'inositol phosphate code' in eukaryotes. Distribution analyses of these four inositol kinase groups throughout the eukaryotic landscape reveal the loss of either ITPK, or of PPIP5K proteins in several species. Surprisingly, the loss of IPPK, an enzyme thought to catalyse the rate limiting step of IP6 (phytic acid) synthesis, was also recorded. Furthermore, this study highlights a noteworthy difference between animal (metazoan) and plant (archaeplastida) lineages. While metazoan appears to have a substantial amplification of IPK enzymes, archaeplastida genomes show a considerable increase in ITPK members. Differential evolution of IPK and ITPK between plant and animal lineage is likely reflective of converging functional adaptation of these two types of inositol kinases. Since, the IPK family comprises three sub-types IPMK, IP6K, and IP3-3K each with dedicated enzymatic specificity in metazoan, we propose that the amplified ITPK group in plant could be classified in sub-types with distinct enzymology.


Assuntos
Células Eucarióticas/enzimologia , Fosfotransferases/metabolismo , Animais , Células Eucarióticas/classificação , Células Eucarióticas/metabolismo , Humanos , Fosfatos de Inositol/química , Fosfatos de Inositol/metabolismo , Família Multigênica , Fosfotransferases/genética , Filogenia , Plantas/enzimologia , Plantas/metabolismo , Transdução de Sinais
15.
Int J Food Microbiol ; 337: 108918, 2021 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-33126075

RESUMO

Major facilitator superfamily (MFS) comprises a large family of fungal transporters. In this work four Penicillium digitatum MFS transporters named PdMFS2-5 were identified and functionally characterized through gene elimination and gene overexpression with aim of unveil the similarities and differences among members of the same family during pathogen-fruit interaction. Fungal mutants in which each of the MFS transporters were individually deleted, displayed a clear effect on their infective capacity during citrus fruit infection especially in two of them. In contrast, the observed effect on fungicide sensitivity limits PdMFS2 and PdMFS3 as transporters underlying fungicide resistance. Moreover, overexpression transformants confirmed P. digitatum MFS transporters function and PdMFS2 and PdMFS3 were able to confer fungicide resistance to P. digitatum strains originally fungicide sensitive. Gene transcription rate depended on each MFS transporter being PdMFS4 the one with higher gene expression. Transcriptional profiling was similar regardless the P. digitatum strain. The gene expression analysis showed an increase of PdMFSs transcription in all overexpression transformants, particularly in Pd27 strain. Expression analysis carried out during P. digitatum-citrus fruit interaction confirmed the contribution of all PdMFSs, excepting PdMFS5, in fungal virulence. These results indicate that MFS fungal transporters might be part of different processes and can replace other genes functions giving them a very high degree of versatility.


Assuntos
Citrus/microbiologia , Microbiologia de Alimentos , Interações Hospedeiro-Patógeno/genética , Penicillium/metabolismo , Fungicidas Industriais , Regulação Fúngica da Expressão Gênica , Proteínas de Membrana Transportadoras/genética , Penicillium/genética , Virulência/genética
16.
J. Health Biol. Sci. (Online) ; 9(1): 1-5, 2021. tab
Artigo em Português | LILACS | ID: biblio-1352408

RESUMO

Objetivo: verificar se o ângulo de fase, obtido por bioimpedância elétrica, pode ser utilizado como indicador prognóstico em doenças infecciosas e em quais dessas doenças seu uso está adequadamente embasado pela literatura científica. Métodos: revisão integrativa realizada por meio das bases de dados, como google acadêmico, na BVS Brasil, nas bases SciELO, LILACS e Pubmed, utilizando o termo para busca (bioimpedância e doenças infectocontagiosas e bioimpedância) AND (bioimpedance and infectious diseases OR bioimpedance). A seleção dos estudos foi feita, considerando artigos originais completos disponíveis on-line, em inglês, espanhol e português, publicados entre 2007 e 2021. Resultados: todos os estudos considerados (793) foram realizados em adultos com doença infecciosa. Destes 28 (3,5%) foram separados para leitura aprofundada sobre o perfil metodológico, e apenas quatro (0,50%) do total de artigos consideraram o ângulo de fase como índice prognóstico para doenças infeciosas, ambos em pacientes HIV + hospitalizados. Conclusão: A bioimpedância vem sendo considerada como instrumento de avaliação de estado nutricional em pacientes com doenças infecciosas. Mas o uso do ângulo de fase vem sendo pouco estudado como índice prognóstico para essa população, não podendo ser considerado adequadamente embasado para uso clínico na população com doença infecciosa, o que suscita maior atenção a esta população e a necessidade de maior investigação científica.


Objective: to verify if the phase angle obtained by electrical bioimpedance can be used as a prognostic indicator in infectious diseases and in which infectious diseases its use is adequately supported by scientific literature. Methods: integrative review conducted using databases such as Google Scholar, BVS Brazil, SciELO, LILACS and Pubmed, using the search term (bioimpedance and infectious diseases and bioimpedance) AND (bioimpedance and infectious diseases OR bioimpedance). The selection of studies was made considering complete original articles available online, in English, Spanish and Portuguese, published between 2007 and 2021. Results: all studies considered (793) were carried out in adults with infectious disease. Of these, 28 (3.5%) were separated for in-depth reading on the methodological profile, and only four (0.50%) of the total articles considered the phase angle as a prognostic index for infectious diseases, both in hospitalized HIV + patients. Conclusion: Bioimpedance has been considered as an instrument to assess nutritional status in patients with infectious diseases. However, the use of the phase angle has been little studied as a prognostic index for this population, and cannot be considered adequately substantiated for clinical use in the population with infectious disease, which raises more attention to this population and the need for further scientific investigation.


Assuntos
Impedância Elétrica , Prognóstico , Estado Nutricional , Doenças Transmissíveis
17.
Biotechnol Biofuels ; 13(1): 198, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33372612

RESUMO

BACKGROUND: Xylanases are one of the most extensively used enzymes for biomass digestion. However, in many instances, their use is limited by poor performance under the conditions of pH and temperature required by the industry. Therefore, the search for xylanases able to function efficiently at alkaline pH and high temperature is an important objective for different processes that use lignocellulosic substrates, such as the production of paper pulp and biofuels. RESULTS: A comprehensive in silico analysis of family GH11 sequences from the CAZY database allowed their phylogenetic classification in a radial cladogram in which sequences of known or presumptive thermophilic and alkalophilic xylanases appeared in three clusters. Eight sequences from these clusters were selected for experimental analysis. The coding DNA was synthesized, cloned and the enzymes were produced in E. coli. Some of these showed high xylanolytic activity at pH values > 8.0 and temperature > 80 °C. The best enzymes corresponding to sequences from Dictyoglomus thermophilum (Xyn5) and Thermobifida fusca (Xyn8). The addition of a carbohydrate-binding module (CBM9) to Xyn5 increased 4 times its activity at 90 °C and pH > 9.0. The combination of Xyn5 and Xyn8 was proved to be efficient for the saccharification of alkali pretreated rice straw, yielding xylose and xylooligosaccharides. CONCLUSIONS: This study provides a fruitful approach for the selection of enzymes with suitable properties from the information contained in extensive databases. We have characterized two xylanases able to hydrolyze xylan with high efficiency at pH > 8.0 and temperature > 80 °C.

18.
Pestic Biochem Physiol ; 165: 104522, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32359549

RESUMO

Two sterol 14α-demethylase genes from Penicillium digitatum, PdCYP51A and PdCYP51B, were evaluated and revealed that 95% of Imazalil (IMZ)-resistant isolates carried a 195-bp insertion in the PdCYP51B promoter. We functionally characterized both sterol 14α-demethylases by overexpression. Molecular analysis of overexpression mutants showed that the introduction of PdCYP51B insertion is more stable than the five-tandem repeat PdCYP51A sequence previously described that confers DMI fungicide resistance. The both enhancers can coexist in P. digitatum isolates that initially contained the 195-bp PdCYP51B insertion but the introduction of 195-bp PdCYP51B enhancer promoted the loss of the five-tandem repeat of PdCYP51A. The incorporation of 195-bp PdCYP51B resulted in an increase of DMI fungicide resistance in mutants from already resistant isolates and confers resistance to DMIs in mutants from sensitive isolates. Transcription evaluation of the both genes showed noticeable induction in all overexpression mutants, except for those coming from the five-tandem repeat PdCYP51A sequence, whereas PdCYP51A expression dropped dramatically. Only PdCYP51B exhibited up-regulation during citrus infection compared to axenic growth, and the role of PdCYP51B in fungal virulence was further reinforced since strains with low virulence showed increased infectivity in overexpression mutants. This study suggested the predominant role of the PdCYP51B enhancer in the acquisition of DMI resistance and fungal virulence, by replacing homologues genes with same putative function.


Assuntos
Citrus , Fungicidas Industriais , Penicillium , Farmacorresistência Fúngica , Virulência
19.
Clin Nutr ESPEN ; 34: 32-36, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31677708

RESUMO

BACKGROUND & AIMS: The nutritional status of people with human T-lymphotropic virus (HTLV-1) infection has been poorly described because it involves a neglected disease. The few studies that have been conducted mostly involve people with neurologic consequences and the possible clinical evolutions of the disease. The aim of this study was to describe the nutritional status of patients with HTLV-1, including those with associated myelopathy/tropical spastic paraparesis, and to evaluate food security in these patients. METHODS: A retrospective observational study was conducted in people with HTLV-1 admitted to a referral hospital. We collected data from 17 medical records, including anthropometric data (i.e., body mass index, mid-upper arm circumference, triceps skinfold, and mid-arm muscle circumference), laboratory test results (i.e., haemoglobin, haematocrit, albumin, globulin, iron fixation capacity, and iron), the Subjective Global Assessment (SGA) method, and food security (Brazilian Food Insecurity Scale) data. The data were analysed using the R-project software. To evaluate possible associations between the outcomes and predictors (age at hospitalisation, food security, presence of children <18 years of age living in the household, income, schooling, ANSG, BMI, difference between ideal weight and hospitalisation, TSF, MUAC ICU days, hospitalisation outcome, rehospitalisation in the first year after discharge, interval between readmissions, death, associated conditions, constipation upon admission), we used Kruskal-Wallis, Mann-Whitney, Fisher's exact, chi-square tests with continuity correction, and Spearman's correlation coefficient. Hypothesis tests were considered statistically significant when p ≤ 0.05. RESULTS: The mean age of the patients was 57 (52-60) years. The patients were predominantly women (59%) and had an income lower than the local minimum wage with at least 6 years of schooling (52.3%). Only 18.2% of patients were eutrophic according to their BMI and 23.5% of patients were malnourished based on the SGA method. Patients predominantly had food security (64.7%) and good intestinal functions (64.7%) during their hospital stay. CONCLUSION: Despite having a limited number of patients in this study, HTLV-1 patients admitted to hospital are at high risk of malnutrition based on the scores from the SGA method.


Assuntos
Abastecimento de Alimentos , Infecções por HTLV-I/complicações , Desnutrição/complicações , Estado Nutricional , Obesidade/complicações , Antropometria , Índice de Massa Corporal , Brasil , Feminino , Infecções por HTLV-I/epidemiologia , Hospitalização , Vírus Linfotrópico T Tipo 1 Humano , Humanos , Tempo de Internação , Masculino , Desnutrição/epidemiologia , Pessoa de Meia-Idade , Avaliação Nutricional , Obesidade/epidemiologia , Estudos Retrospectivos
20.
J Fungi (Basel) ; 5(4)2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31635246

RESUMO

A new Penicillium digitatum major facilitator superfamily (MFS) transporter (PdMFS1) was identified and functionally characterized in order to shed more light on the mechanisms underlying fungicide resistance. PdMFS1 can play an important role in the intensification of resistance to fungicides normally used in P. digitatum postharvest treatments. In the PdMFS1 disrupted mutants, a slight effect in response to chemical fungicides was observed, but fungicide sensitivity was highly affected in the overexpression mutants which became resistant to wide range of chemical fungicides. Moreover, P. digitatum knock-out mutants exhibited a lower rate of fungal virulence when infected oranges were stored at 20 °C. Disease symptoms were higher in the PdMFS1 overexpression mutants coming from the low-virulent P. digitatum parental strain. In addition, the gene expression analysis showed an induction of PdMFS1 transcription in all overexpression mutants regardless from which progenitor came from, and four-time intensification of the parental wild type strain during citrus infection reinforcing PdMFS1 role in fungal virulence. The P. digitatum MFS transporter PdMFS1 contributes not only to the acquisition of wide range of fungicide resistance but also in fungal virulence during citrus infection.

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