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Outer-inner membrane vesicles (O-IMVs) were recently described as a new type of membrane vesicle secreted by the Antarctic bacterium Shewanella vesiculosa M7T. Their formation is characterized by the protrusion of both outer and plasma membranes, which pulls cytoplasmic components into the vesicles. To demonstrate that this is not a singular phenomenon in a bacterium occurring in an extreme environment, the identification of O-IMVs in pathogenic bacteria was undertaken. With this aim, a structural study by Transmission Electron Microscopy (TEM) and Cryo-transmission electron microscopy (Cryo-TEM) was carried out, confirming that O-IMVs are also secreted by Gram-negative pathogenic bacteria such as Neisseria gonorrhoeae, Pseudomonas aeruginosa PAO1 and Acinetobacter baumannii AB41, in which they represent between 0.23% and 1.2% of total vesicles produced. DNA and ATP, which are components solely found in the cell cytoplasm, were identified within membrane vesicles of these strains. The presence of DNA inside the O-IMVs produced by N. gonorrhoeae was confirmed by gold DNA immunolabeling with a specific monoclonal IgM against double-stranded DNA. A proteomic analysis of N. gonorrhoeae-derived membrane vesicles identified proteins from the cytoplasm and plasma membrane. This confirmation of O-IMV extends the hitherto uniform definition of membrane vesicles in Gram-negative bacteria and explains the presence of components in membrane vesicles such as DNA, cytoplasmic and inner membrane proteins, as well as ATP, detected for the first time. The production of these O-IMVs by pathogenic Gram-negative bacteria opens up new areas of study related to their involvement in lateral gene transfer, the transfer of cytoplasmic proteins, as well as the functionality and role of ATP detected in these new vesicles.

Progress in the design of G-quadruplex (G4) binding ligands relies on the availability of approaches that assess the binding mode and nature of the interactions between G4 forming sequences and their putative ligands. The experimental approaches used to characterize G4/ligand interactions can be categorized into structure-based methods (circular dichroism (CD), nuclear magnetic resonance (NMR) spectroscopy and X-ray crystallography), affinity and apparent affinity-based methods (surface plasmon resonance (SPR), isothermal titration calorimetry (ITC) and mass spectrometry (MS)), and high-throughput methods (fluorescence resonance energy transfer (FRET)-melting, G4-fluorescent intercalator displacement assay (G4-FID), affinity chromatography and microarrays. Each method has unique advantages and drawbacks, which makes it essential to select the ideal strategies for the biological question being addressed. The structural- and affinity and apparent affinity-based methods are in several cases complex and/or time-consuming and can be combined with fast and cheap high-throughput approaches to improve the design and development of new potential G4 ligands. In recent years, the joint use of these techniques permitted the discovery of a huge number of G4 ligands investigated for diagnostic and therapeutic purposes. Overall, this review article highlights in detail the most commonly used approaches to characterize the G4/ligand interactions, as well as the applications and types of information that can be obtained from the use of each technique.

MicroRNA-155-3p (miR-155-3p) is an important biomarker in various pathological conditions, including cancer, making the development of sensitive and specific detection methods crucial. Here, we present a molecular beacon (MB-G4) that underwent a conformational switch upon hybridization with miR-155-3p, enabling the formation of a G-quadruplex (G4) structure. This G4 was recognized by the fluorogenic ligand N-methyl mesoporphyrin IX (NMM), producing a fluorescence signal proportional to the target concentration, making it a new detection method. The conformational dynamics of MB-G4 were characterized through circular dichroism (CD) spectroscopy and native polyacrylamide gel electrophoresis (PAGE), confirming the transition from a hairpin structure to an RNA–DNA hybrid duplex that facilitated G4 formation. The optimization of the experimental conditions, including the potassium chloride (KCl) and NMM concentrations, ensured selective detection with minimal background signal. The detection limit (LOD) was determined to be 10.85 nM, using a linear fluorescence response curve, and the specificity studies demonstrated a clear distinction between miR-155-3p and miR-155-5p. Furthermore, MB-G4 was studied with total RNA extracted from the lung cancer cell line A549 to evaluate its detection in a more complex environment and was able to detect its target, validating its potential for biological sample analysis.

The ability of fluorescent small molecules, such as metal complexes, to selectively recognize G-quadruplex (G4) structures has opened a route to develop new probes for the visualization of these DNA structures in cells. The main goal of this review is to update the most recent research efforts towards the development of novel cancer theranostic agents using this type of metal-based probes that specifically recognize G4 structures. This encompassed a comprehensive overview of the most significant progress in the field, namely based on complexes with Cu, Pt, and Ru that are among the most studied metals to obtain this class of molecules. It is also discussed the potential interest of obtaining G4-binders with medical radiometals (e.g., 99mTc, 111In, 64Cu, 195mPt) suitable for diagnostic and/or therapeutic applications within nuclear medicine modalities, in order to enable their theranostic potential.

Marine brown algae produce the highly recalcitrant polysaccharide fucoidan, contributing to long-term oceanic carbon storage and climate regulation. Fucoidan is degraded by specialized heterotrophic bacteria, which promote ecosystem function and global carbon turnover using largely uncharacterized mechanisms. Here, we isolate and study two Planctomycetota strains from the microbiome associated with the alga Fucus spiralis , which grow efficiently on chemically diverse fucoidans. One of the strains appears to internalize the polymer, while the other strain degrades it extracellularly. Multi-omic approaches show that fucoidan breakdown is mediated by the expression of divergent polysaccharide utilization loci, and endo-fucanases of family GH168 are strongly upregulated during fucoidan digestion. Enzymatic assays and structural biology studies reveal how GH168 endo-fucanases degrade various fucoidan cores from brown algae, assisted by auxiliary hydrolytic enzymes. Overall, our results provide insights into fucoidan processing mechanisms in macroalgal-associated bacteria. Degradation of the recalcitrant polysaccharide fucoidan, produced by marine brown algae, is carried out by some bacteria through unclear mechanisms. Here, the authors provide insights into fucoidan processing mechanisms by studying two alga-associated bacterial strains, using microscopy, multi-omic, biochemical and structural techniques.

Background/Objectives: In Ecuador, the prevalence of type 2 diabetes mellitus (T2DM) is the second leading cause of death after ischemic heart disease. Genetic variability in protein-coding genes, single nucleotide variants (SNVs), influences the response to antidiabetic drugs. The frequency of SNVs varies among different populations, so studying the ancestral proportions among SNVs is important for personalized medicine in the treatment of T2DM. This study aimed to evaluate the distribution of Native American, European, and African (NATAM, EUR, and AFR) ancestry in 23 allelic variants of the seven genes that encode the relevant enzymes that metabolize antidiabetic drugs in an Ecuadorian population. Methods: Twenty-three allelic variants of seven genes were analyzed in 297 patients with T2DM from Ecuador, and the molecular ancestry of the samples was analyzed considering three ancestral groups, NATAM, EUR, and AFR using 90 ancestry informative markers (AIMs). Allele and ancestry distributions were analyzed using Spearman’s correlation. Results: The Ecuadorian population presents NATAM (61.33%), EUR (34.48%), and AFR (2.60%) ancestry components. CYP2C8*1 and CYP2C9*1 were positively related to NATAM ancestry, while CYP2C8*4 and CYP2C9*2 were positively related to EUR ancestry. CYP2C19*17 was positively correlated to AFR ancestry. The correlation of SLC22A1 variants such as A in rs594709 was positively correlated with NATAM, while GAT in rs72552763 was positive for EUR. The G variant of rs628031 of the SLC22A1 gene was positively correlated with NATAM and negatively correlated with EUR. The C variant of rs2076828 of the SLC22A3 gene was positively correlated with NATAM ancestry. Conclusions: In the Ecuadorian population, a predominance of Native American ancestry has been observed. Among the allelic variants related to enzymes that metabolize antidiabetic drugs, a relationship has been observed between this ancestral component and variants of the CYP2C8*1, CYP2C9*1, SLC22A1 (rs594709 and rs628031), and SLC22A3 (rs2076828) genes. This information is fundamental for the development of strategies for the implementation of personalized medicine programs for Latin American patients.

The COVID-19 pandemic has forced policy makers to decree urgent confinements to stop a rapid and massive contagion. However, after that stage, societies are being forced to find an equilibrium between the need to reduce contagion rates and the need to reopen their economies. The experience hitherto lived has provided data on the evolution of the pandemic, in particular the population dynamics as a result of the public health measures enacted. This allows the formulation of forecasting mathematical models to anticipate the consequences of political decisions. Here we propose a model to do so and apply it to the case of Portugal. With a mathematical deterministic model, described by a system of ordinary differential equations, we fit the real evolution of COVID-19 in this country. After identification of the population readiness to follow social restrictions, by analyzing the social media, we incorporate this effect in a version of the model that allow us to check different scenarios. This is realized by considering a Monte Carlo discrete version of the previous model coupled via a complex network. Then, we apply optimal control theory to maximize the number of people returning to “normal life” and minimizing the number of active infected individuals with minimal economical costs while warranting a low level of hospitalizations. This work allows testing various scenarios of pandemic management (closure of sectors of the economy, partial/total compliance with protection measures by citizens, number of beds in intensive care units, etc.), ensuring the responsiveness of the health system, thus being a public health decision support tool.

AS1411 is a G-rich DNA oligonucleotide that functions as an aptamer of the protein nucleolin, found at high levels on the surface of cancer cells but not on the surface of normal cells. Herein, we have studied AS1411 as a supramolecular carrier for the delivery of an acridine-based G-quadruplex ligand, C 8 , to HeLa cancer cells. Two AS1411 derivatives, LNA-AS1411 and U-AS1411, were also tested, in an attempt to compare AS1411 pharmacological properties. The results showed that AS1411-C 8 complexation was made with great binding strength and that it lowered the ligand’s cytotoxicity towards non-malignant cells. This effect was suggested to be due to a decreased internalization of the complexed versus free C 8 as shown by flow cytometry. The AS1411 derivatives, despite forming a stable complex with C 8 , lacked the necessary tumour-selective behaviour. The binding of C 8 to AS1411 G-quadruplex structure did not negatively affect the recognition of nucleolin by the aptamer. The AS1411-C 8 repressed c-MYC expression at the transcriptional level, possibly due to C 8 ability to stabilize the c-MYC promoter G-quadruplexes. Overall, this study demonstrates the usefulness of AS1411 as a supramolecular carrier of the G-quadruplex binder C 8 and the potential of using its tumour-selective properties for the delivery of ligands for cancer therapy.

Research on pharmacogenetic variability in response to prescribed drugs and across ethnic groups is essential for personalized medicine, particularly in admixed and unstudied populations. For the first time, this study examines CYP2D6, CYP2C9, and CYP2C19 alleles and genotypes in 197 healthy volunteers from the Dominican Republic, as part of the RIBEF-CEIBA collaborative network. Methods: The analysis focuses on the participants’ tri-hybrid genomic ancestry, with CYP alleles determined by real-time PCR and molecular ancestry inferred using 90 AIMs. Linear regression was used to associate ancestry components with CYP frequencies. Results: The average ancestry was 23.8% European, 42.6% Native American, and 33.6% African, the latter being higher than in most Latin American populations. Native American ancestry was also higher than expected. Predicted phenotype frequencies based on genotypes were 4.2% poor metabolizers (gPMs) and 3.6% ultrarapid metabolizers (gUMs) for CYP2D6, as well as 3% gPMs, 22.8% rapid metabolizers (gRMs), and 1.5% gUMs for CYP2C19. No gPM individuals were observed for CYP2C9. Certain alleles associated with decreased CYP2D6 activity (*17 and *29) and increased CYP2C19 activity (*17 and gUMs) were positively linked with African ancestry and negatively with Native American ancestry. Rare CYP2C9 alleles (*5 and *6) with clinical relevance were additionally found. Conclusions: These findings build on previous results from the RIBEF-CEIBA collaborative network, demonstrating differences in allele frequencies of CYP2D6, CYP2C9, and CYP2C19 in relation to genomic ancestry. In summary, ethnicity must be considered in the development of pharmacogenetic guidelines for clinical application, research, and regulation to avoid widening the biotechnology gap and to allow Personalized Medicine to reach the entire world population.

A variable number tandem repeat polymorphism has been described in the CYP2C9 promoter (pVNTR) with three types of fragments: short (pVNTR-S), medium (pVNTR-M), and long (pVNTR-L). The pVNTR-S allele appears in strong linkage disequilibrium (LD) with the non-functional CYP2C9*3 allele in populations of European ancestry, but independently of this, it also appears to reduce the level of CYP2C9 expression in human liver by up to 34%. Objectives: This study, in a Dominican population with varying amounts of Western European, African, and Native American ancestry, aims primarily to determine the frequency of CYP2C9 pVNTR, and the degree of LD of pVNTR-S with CYP2C9*3. Secondarily, it explores if the frequency of the pVNTR-S allele is over- or under-represented in those with a greater component of African ancestry. Methods: A total of 193 healthy volunteers from the Dominican Republic participated in the study. The promoter region of CYP2C9 was amplified and analyzed by capillary electrophoresis. Analyses of CYP2C9 genotypes (*2, *3, *5, *6, and *8) and genetic ancestry, estimated in 176 Dominican individuals by genotyping 90 ancestry informative markers, were previously performed in this population. Results: The frequencies of CYP2C9 pVNTR-L, M, and S variants are 0.065, 0.896, and 0.039, respectively. LD between pVNTR-S and CYP2C9*3 was found (D’ = 0.756, r2 = 0.702) to be weaker than in European populations. Conclusions: Populations with a greater African ancestry component appear to present a lower-than-expected frequency of pVNTR-S, as well as a lower tendency for this and CYP2C9*3 alleles to be inherited together, as is common in Europeans. The present exploratory results warrant further research in vivo about the effects of pVNTR-S in predicting CYP2C9 activity. Its inclusion in CYP2C9 testing panels for personalized drug therapy could be relevant in populations such as the Dominican, where the LD between pVNTR-S and CYP2C9*3 is low.