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Phytophthora palmivora, a hemibiotrophic oomycete, causes diseases in several economically important tropical crops, such as oil palm, which it is responsible for a devastating disease called bud rot (BR). Despite recent progress in understanding host resistance and virulence mechanisms, many aspects remain unknown in P. palmivora isolates from oil palm. Model pathosystems are useful for understanding the molecular interactions between pathogens and hosts. In this study, we utilized detached leaves and whole seedlings of Arabidopsis thaliana Col-0 to describe and evaluate the infection process of three P. palmivora isolates (CPPhZC-05, CPPhZC-04, CPPhZOC-01) that cause BR in oil palm. Two compatible isolates (CPPhZC-05 and CPPhZOC-01) induced aqueous lesions at 72 h post-inoculation (hpi), with microscopic visualization revealing zoospore encysting and appressorium penetration at 3 hpi, followed by sporangia generation at 72 hpi. In contrast, an incompatible isolate (CPPhZC-04) exhibited cysts that could not penetrate tissue, resulting in low leaf colonization. Gene expression of ten P. palmivora infection-related genes was quantified by RT-qPCR, revealing overexpression in compatible isolates, but not in the incompatible isolate. Additionally, key genes associated with salicylic acid (SA), jasmonic acid (JA), and ethylene (ET) in Arabidopsis exhibited regulation during interaction with the three isolates. These findings demonstrate that P. palmivora can infect Arabidopsis Col-0, and variability is observed in the interaction between Arabidopsis-Col-0 and P. palmivora isolates. Establishing this pathosystem is expected to enhance our understanding of P. palmivora's pathology and physiology.

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Multiple sclerosis (MS) is a common disease in young women of reproductive age, characterized by demyelination of the central nervous system (CNS). Understanding how genes related to MS are expressed during pregnancy can provide insights into the potential mechanisms by which pregnancy affects the course of this disease. This review article presents evidence-based studies on these patients' gene expression patterns. In addition, it constructs interaction networks using bioinformatics tools, such as STRING and KEGG pathways, to understand the molecular role of each of these genes. Bioinformatics research identified 25 genes and 21 signaling pathways, which allows us to understand pregnancy patients' genetic and biological phenomena and formulate new questions about MS during pregnancy.

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Leishmaniasis is a disease caused by a protozoan of the genus Leishmania, affecting millions of people, mainly in tropical countries, due to poor social conditions and low economic development. First-line chemotherapeutic agents involve highly toxic pentavalent antimonials, while treatment failure is mainly due to the emergence of drug-resistant strains. Leishmania arginase (ARG) enzyme is vital in pathogenicity and contributes to a higher infection rate, thus representing a potential drug target. This study helps in designing ARG inhibitors for the treatment of leishmaniasis. Py-CoMFA (3D-QSAR) models were constructed using 34 inhibitors from different chemical classes against ARG from L. (L.) amazonensis (LaARG). The 3D-QSAR predictions showed an excellent correlation between experimental and calculated pIC50 values. The molecular docking study identified the favorable hydrophobicity contribution of phenyl and cyclohexyl groups as substituents in the enzyme allosteric site. Molecular dynamics simulations of selected protein-ligand complexes were conducted to understand derivatives' interaction modes and affinity in both active and allosteric sites. Two cinnamide compounds, 7g and 7k, were identified, with similar structures to the reference 4h allosteric site inhibitor. These compounds can guide the development of more effective arginase inhibitors as potential antileishmanial drugs.

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Significant scientific advances to elucidate the Moniliophthora perniciosa pathosystem have been achieved in recent years, but the molecular biology of this pathogen-host interaction is still a field with many unanswered questions. In order to present insights at the molecular level, we present the first systematic review on the theme. All told, 1118 studies were extracted from public databases. Of these, 109 were eligible for the review, based on the inclusion and exclusion criteria. The results indicated that understanding the transition from the biotrophic-necrotrophic phase of the fungus is crucial for control of the disease. Proteins with strong biotechnological potential or that can be targets for pathosystem intervention were identified, but studies regarding possible applications are still limited. The studies identified revealed important genes in the M. perniciosa-host interaction and efficient molecular markers in the search for genetic variability and sources of resistance, with Theobroma cacao being the most common host. An arsenal of effectors already identified and not explored in the pathosystem were highlighted. This systematic review contributes to the understanding of the pathosystem at the molecular level, offering new insights and proposing different paths for the development of new strategies to control witches' broom disease.

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The structures and molecular interactions of established synthetic chalcones were correlated with their release profiles from asolectin liposomes. The effects of chalcones on the properties of liposomes were evaluated by dynamic light scattering (DLS), ultraviolet-visible spectroscopy (UV-VIS), horizontal attenuated total reflection Fourier transform infrared (HATR-FTIR), 31P nuclear magnetic resonance (31P NMR), zeta (ζ) potential and differential scanning calorimetry (DSC). The profiles and mechanisms of release were accessed according to the Korsmeyer-Peppas model. Results obtained allowed the establishment of a relationship between the chalcone release profile and 1) the ordering effects of chalcones in different membrane regions, 2) their polar or interfacial location in the lipid layer, 3) the influence of hydroxy and methoxy substituents, 4) their effect on reorientation of lipid choline-phosphate regions. The obtained data may improve the development of chalcone-based systems to be used in the therapy of chronic and acute diseases.

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There is not a consensus between the presence of the genotypic resistance marker gene and the phenotypic resistance to ß-lactams in Staphylococcus aureus, which means, positive S. aureus blaZ isolates demonstrating sensitivity to ß-lactams. The present study aimed to characterize the blaZ, blaR1 and blaI genes, identify and evaluate single nucleotide polymorphisms (SNPs) and their relationship with ß-lactam resistance in samples of Staphylococcus aureus obtained from cases of bovine mastitis. Five isolates (two resistant and three sensitive to oxacillin) of Staphylococcus aureus with detected production of beta-lactamase, previously evaluated as containing the blaZ gene and negative for the mecA and mecC genes, had the bla operon completely sequenced. Impacts on the protein sequence due to the detected polymorphisms were evaluated by modeling the proteins encoded by the blaZ, blaR1 and blaI genes using a three-dimensional model structure obtained from the Protein Data Bank (PDB) database. Fifteen SNPs were detected in the blaZ gene, 30 in the blaR1 gene and three in the blaI gene. These SNPs caused alterations in amino acid sites. Deleterious mutations were detected in the blaZ gene (E146G, P218S, Y221C) and the blaR1 gene (K481E). Molecular docking analysis revealed that polymorphisms in the blaZ gene may explain the phenotypic sensitivity in isolates that contain the resistance marker gene. Although sensitive and resistant isolates encode beta-lactamase, these proteins are functionally altered due to a change in the binding site with the antibiotic.

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Activated carbons are well-known porous materials as an effective adsorbent used for the removal of emerging contaminants, such as herbicides, which are increasingly present in water bodies. Most water treatment plants, specially in Brazil, are unable to completely remove such contaminants by the conventional process and advanced treatment using activated carbons is required. The aim of this paper was to verify the influence of the activated carbons granulometry and specific surface area on the 2,4-dichlorophenoxyacetic acid (2,4-D) herbicide removal efficiency using distilled-deionized water and filtered water collected from a conventional Water Treatment Plant. Commercial activated carbons samples used in this work were obtained from two different manufacturers. Activated carbons were analyzed by the specific surface area, pore size and volume distribution, nuclear magnetic resonance, infrared and x-ray spectroscopy, moisture, volatile matter and ash contents. Batch adsorption isotherms experiments were used and performed by Langmuir and Freundlich models. Granular and powdered activated carbons removed over 99% of 2,4-D in distilled water and near to 99% using filtered water. The activated carbons evaluated in this work presented high performance and played a key role in water treatment by removing 2,4-D herbicide, ensuring the protection of human health and the ecosystem.

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The cellular response to hypoxia is crucial to organismal survival, and hypoxia-inducible factors (HIF) are the key mediators of this response. HIF-signaling is central to many human diseases and mediates longevity in the nematode. Despite the rapidly increasing knowledge on RNA-binding proteins (RBPs), little is known about their contribution to hypoxia-induced cellular adaptation. We used RNA interactome capture (RIC) in wild-type Caenorhabditis elegans and vhl-1 loss-of-function mutants to fill this gap. This approach identifies more than 1,300 nematode RBPs, 270 of which can be considered novel RBPs. Interestingly, loss of vhl-1 modulates the RBPome. This difference is not primarily explained by protein abundance suggesting differential RNA-binding. Taken together, our study provides a global view on the nematode RBPome and proteome as well as their modulation by HIF-signaling. The resulting RBP atlas is also provided as an interactive online data mining tool (http://shiny.cecad.uni-koeln.de:3838/celegans_rbpome).

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Rose Bengal@α-cyclodextrin (RB@α-CD) microparticles (µPs) were prepared and the RB inclusion in α-CD was experimentally demonstrated through infrared, UV-VIS absorption spectroscopy and cyclic voltammetry. The RB inclusion in α-CD was theoretically investigated using classical molecular mechanics calculations, the simulation results showing that RB can be included in both the narrow and wide apertures of the α-cyclodextrin ring with configurations exhibiting average binding energies of about 27 kcal mol-1. The prepared RB@α-CD microparticles were characterized through Scanning Electron Microscopy (SEM) and it was demonstrated that they are highly efficient in the photodynamic therapy against a Streptococcus mutans (the main bacteria of cariogenic dental plaque) suspension, as a concentration of RB@α-CD µPs 10 times smaller than the usual concentration of pure RB is still capable to produce significant antibacterial activity.

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Farnesoid X receptor (FXR) is a nuclear receptor related to lipid and glucose homeostasis and is considered an important molecular target to treatment of metabolic diseases as diabetes, dyslipidemia, and liver cancer. Nowadays, there are several FXR agonists reported in the literature and some of it in clinical trials for liver disorders. Herein, a compound series was employed to generate QSAR models to better understand the structural basis for FXR activation by anthranilic acid derivatives (AADs). Furthermore, here we evaluate the inclusion of the standard deviation (SD) of EC50 values in QSAR models quality. Comparison between the use of experimental variance plus average values in model construction with the standard method of model generation that considers only the average values was performed. 2D and 3D QSAR models based on the AAD data set including SD values showed similar molecular interpretation maps and quality (Q2LOO, Q2(F2), and Q2(F3)), when compared to models based only on average values. SD-based models revealed more accurate predictions for the set of test compounds, with lower mean absolute error indices as well as more residuals near zero. Additionally, the visual interpretation of different QSAR approaches agrees with experimental data, highlighting key elements for understanding the biological activity of AADs. The approach using standard deviation values may offer new possibilities for generating more accurate QSAR models based on available experimental data.

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Combination of ß-lactoglobulin (ß-Lg) and lactoferrin (Lf), biomacromolecules derived from bovine whey, was used in the formation of supramolecular structures by thermal gelation technique to adjust the pH. Furthermore, the influence of the molar ratio, temperature, pH, and heating time in the formation of supramolecular structures were also studied. The characterization of the protein supramolecular structures was performed using dynamic light scattering, zeta potential measurements, molecular spectrofluorimetry, and circular dichroism spectroscopy. The thermal behavior of the pure proteins was investigated by differential scanning calorimetry. The protein denaturation temperatures were of around 85°C for the ß-Lg and around 52°C and 85°C (a small portion) for the Lf. The protein molar ratio of 2:1 Lf/ß-Lg was used to form the structures, whose characterization showed that the best conditions of supramolecular structure formation occurred at pH6.5 and at temperatures of 62.5°C. In those conditions, more stable systems with reduced hydrophobic surface and average sizes between 30 and 100nm were generated. The correlation between pH and temperature suggests that the method of preparation of the supramolecular structure affects its size during storage.

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The microorganism-microorganism or microorganism-host interactions are the key strategy to colonize and establish in a variety of different environments. These interactions involve all ecological aspects, including physiochemical changes, metabolite exchange, metabolite conversion, signaling, chemotaxis and genetic exchange resulting in genotype selection. In addition, the establishment in the environment depends on the species diversity, since high functional redundancy in the microbial community increases the competitive ability of the community, decreasing the possibility of an invader to establish in this environment. Therefore, these associations are the result of a co-evolution process that leads to the adaptation and specialization, allowing the occupation of different niches, by reducing biotic and abiotic stress or exchanging growth factors and signaling. Microbial interactions occur by the transference of molecular and genetic information, and many mechanisms can be involved in this exchange, such as secondary metabolites, siderophores, quorum sensing system, biofilm formation, and cellular transduction signaling, among others. The ultimate unit of interaction is the gene expression of each organism in response to an environmental (biotic or abiotic) stimulus, which is responsible for the production of molecules involved in these interactions. Therefore, in the present review, we focused on some molecular mechanisms involved in the microbial interaction, not only in microbial-host interaction, which has been exploited by other reviews, but also in the molecular strategy used by different microorganisms in the environment that can modulate the establishment and structuration of the microbial community.(AU)

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ABSTRACT The microorganism-microorganism or microorganism-host interactions are the key strategy to colonize and establish in a variety of different environments. These interactions involve all ecological aspects, including physiochemical changes, metabolite exchange, metabolite conversion, signaling, chemotaxis and genetic exchange resulting in genotype selection. In addition, the establishment in the environment depends on the species diversity, since high functional redundancy in the microbial community increases the competitive ability of the community, decreasing the possibility of an invader to establish in this environment. Therefore, these associations are the result of a co-evolution process that leads to the adaptation and specialization, allowing the occupation of different niches, by reducing biotic and abiotic stress or exchanging growth factors and signaling. Microbial interactions occur by the transference of molecular and genetic information, and many mechanisms can be involved in this exchange, such as secondary metabolites, siderophores, quorum sensing system, biofilm formation, and cellular transduction signaling, among others. The ultimate unit of interaction is the gene expression of each organism in response to an environmental (biotic or abiotic) stimulus, which is responsible for the production of molecules involved in these interactions. Therefore, in the present review, we focused on some molecular mechanisms involved in the microbial interaction, not only in microbial-host interaction, which has been exploited by other reviews, but also in the molecular strategy used by different microorganisms in the environment that can modulate the establishment and structuration of the microbial community.

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The microorganism-microorganism or microorganism-host interactions are the key strategy to colonize and establish in a variety of different environments. These interactions involve all ecological aspects, including physiochemical changes, metabolite exchange, metabolite conversion, signaling, chemotaxis and genetic exchange resulting in genotype selection. In addition, the establishment in the environment depends on the species diversity, since high functional redundancy in the microbial community increases the competitive ability of the community, decreasing the possibility of an invader to establish in this environment. Therefore, these associations are the result of a co-evolution process that leads to the adaptation and specialization, allowing the occupation of different niches, by reducing biotic and abiotic stress or exchanging growth factors and signaling. Microbial interactions occur by the transference of molecular and genetic information, and many mechanisms can be involved in this exchange, such as secondary metabolites, siderophores, quorum sensing system, biofilm formation, and cellular transduction signaling, among others. The ultimate unit of interaction is the gene expression of each organism in response to an environmental (biotic or abiotic) stimulus, which is responsible for the production of molecules involved in these interactions. Therefore, in the present review, we focused on some molecular mechanisms involved in the microbial interaction, not only in microbial-host interaction, which has been exploited by other reviews, but also in the molecular strategy used by different microorganisms in the environment that can modulate the establishment and structuration of the microbial community.

Assuntos

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ABSTRACT The microorganism-microorganism or microorganism-host interactions are the key strategy to colonize and establish in a variety of different environments. These interactions involve all ecological aspects, including physiochemical changes, metabolite exchange, metabolite conversion, signaling, chemotaxis and genetic exchange resulting in genotype selection. In addition, the establishment in the environment depends on the species diversity, since high functional redundancy in the microbial community increases the competitive ability of the community, decreasing the possibility of an invader to establish in this environment. Therefore, these associations are the result of a co-evolution process that leads to the adaptation and specialization, allowing the occupation of different niches, by reducing biotic and abiotic stress or exchanging growth factors and signaling. Microbial interactions occur by the transference of molecular and genetic information, and many mechanisms can be involved in this exchange, such as secondary metabolites, siderophores, quorum sensing system, biofilm formation, and cellular transduction signaling, among others. The ultimate unit of interaction is the gene expression of each organism in response to an environmental (biotic or abiotic) stimulus, which is responsible for the production of molecules involved in these interactions. Therefore, in the present review, we focused on some molecular mechanisms involved in the microbial interaction, not only in microbial-host interaction, which has been exploited by other reviews, but also in the molecular strategy used by different microorganisms in the environment that can modulate the establishment and structuration of the microbial community.

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Pharmaceutical research has successfully incorporated a wealth of molecular modeling methods, within a variety of drug discovery programs, to study complex biological and chemical systems. The integration of computational and experimental strategies has been of great value in the identification and development of novel promising compounds. Broadly used in modern drug design, molecular docking methods explore the ligand conformations adopted within the binding sites of macromolecular targets. This approach also estimates the ligand-receptor binding free energy by evaluating critical phenomena involved in the intermolecular recognition process. Today, as a variety of docking algorithms are available, an understanding of the advantages and limitations of each method is of fundamental importance in the development of effective strategies and the generation of relevant results. The purpose of this review is to examine current molecular docking strategies used in drug discovery and medicinal chemistry, exploring the advances in the field and the role played by the integration of structure- and ligand-based methods.

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