3-Substituted Coumarins Inhibit NorA and MepA Efflux Pumps of Staphylococcus aureus.

Coumarins are compounds with scientifically proven antibacterial properties, and modifications to the chemical structure are known to improve their effects. This information is even more relevant with the unbridled advances of antibiotic resistance, where Staphylococcus aureus and its efflux pumps play a prominent role. The study's objective was to evaluate the potential of synthetic coumarins with different substitutions in the C-3 position as possible inhibitors of the NorA and MepA efflux pumps of S. aureus. For this evaluation, the following steps took place: (i) the determination of the minimum inhibitory concentration (MIC); (ii) the association of coumarins with fluoroquinolones and ethidium bromide (EtBr); (iii) the assessment of the effect on EtBr fluorescence emission; (iv) molecular docking; and (v) an analysis of the effect on membrane permeability. Coumarins reduced the MICs of fluoroquinolones and EtBr between 50% and 87.5%. Coumarin C1 increased EtBr fluorescence emission between 20 and 40% by reinforcing the evidence of efflux inhibition. The molecular docking results demonstrated that coumarins have an affinity with efflux pumps and establish mainly hydrogen bonds and hydrophobic interactions. Furthermore, C1 did not change the permeability of the membrane. Therefore, we conclude that these 3-substituted coumarins act as inhibitors of the NorA and MepA efflux pumps of S. aureus.

Inhibition of the norA gene expression and the NorA efflux pump by the tannic acid.

The NorA efflux pump of Staphylococcus aureus is known to play a major role in the development of resistance against quinolone drugs by reducing their concentration inside target pathogens. The objective of this study was to evaluate the ability of tannic acid to inhibit the gene expression of the NorA efflux pump in Staphylococcus aureus and to evaluate the in silico effect on the pump. Efflux pump inhibition was evaluated by fluorimetry. The checkerboard method evaluates the effect of the test substance in combination with an antimicrobial at different concentrations. To gene expression evaluation NorA the assay was performed using: a sub-inhibitory concentration preparation (MIC/4) of the antibiotic; a sub-inhibitory concentration preparation (MIC/4) of the antibiotic associated with tannic acid at a sub-inhibitory concentration (MIC/4). In this study, docking simulations were performed by the SWISSDOCK webserver. The ability of tannic acid to inhibit the NorA efflux pump can be related to both the ability to inhibit the gene expression of this protein, acting on signaling pathways involving the ArlRS membrane sensor. As well as acting directly through direct interaction with the NorA protein, as seen in the approach and in silico and in vitro per checkerboard method and fluorimetry of bromide accumulated in the cell.

Antibacterial and Toxic Activity of Geopropolis Extracts from Melipona subnitida (Ducke, 1910) (Hymenoptera: Apidae) and Scaptotrigona depilis (Moure, 1942) (Hymenoptera: Apidae).

Bacteria are associated with many infections that affect humans and present antibiotic resistance mechanisms, causing problems in health organisations and increased mortality rates. Therefore, it is necessary to find new antibacterial agents that can be used in the treatment of these microorganisms. Geopropolis is a natural product from stingless bees, formed by a mixture of plant resins, salivary secretions, wax and soil particles, the chemical composition of this natural product is diverse. Thus, this study aimed to evaluate antibacterial activity, antibiotic modulation and the toxicity of geopropolis extracts from the stingless bees, Melipona subnitida (Ducke, 1910) and Scaptotrigona depilis (Moure, 1942) against standard and multi-resistant Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa bacteria. Geopropolis samples were collected in a meliponary located in Camaragibe, Pernambuco, Brazil. To determine the Minimum Inhibitory Concentration (MIC) and antibiotic modulation we performed broth microdilution tests. Mortality tests were used to verify extract toxicity in the model Drosophila melanogaster. The microbiological tests showing that the M. subnitida extracts had better inhibitory effects compared to S. depilis, presenting direct antibacterial activity against standard and multi-resistant strains. The extracts potentialized antibiotic effects, suggesting possible synergy and did not present toxicity in the model used. The information obtained in this study highlights extracts as promising antibacterial agents and is the first study to evaluate bacterial activity in these extracts, in addition to verifying their modulating effects and determining toxicity in the model used.

Diversity of Colletotrichum species associated with torch ginger anthracnose.

Anthracnose caused by Colletotrichum species is one of the most important diseases of torch ginger. The disease leads to loss of aesthetic and commercial value of torch ginger stems. This study aimed to characterize Colletotrichum species associated with torch ginger anthracnose in the production areas of Pernambuco and Ceará. A total of 48 Colletotrichum isolates were identified using molecular techniques. Pathogenicity tests were performed on torch ginger with representative isolates. Phylogenetic analyses based on seven loci-DNA lyase (APN2), intergenic spacer between DNA lyase and the mating-type locus MAT1-2-1 (APN2/MAT-IGS), calmodulin (CAL), intergenic spacer between glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and a hypothetical protein (GAP2-IGS), glutamine synthetase (GS), and ß-tubulin (TUB2)-revealed that they belong to five known Colletotrichum species, namely, C. chrysophilum, C. fructicola, C. siamense, C. theobromicola, and C. tropicale, and three newly discovered species, described here as C. atlanticum, C. floscerae, and C. zingibericola. Of these, C. atlanticum was the most dominant. Pathogenicity assays showed that all isolates were pathogenic to torch ginger bracts. All species are reported for the first time associated with torch ginger in Brazil. The present study contributes to the current understanding of the diversity of Colletotrichum species associated with anthracnose on torch ginger and demonstrates the importance of accurate species identification for effective disease management strategies.

Allele Frequencies and Forensic Data of 25 STR Markers for Individuals in Northeast Brazil.

Identifying DNA markers such as Short Tandem Repeats (STR) can be used to investigate genetic diversity based on levels of heterozygosity within and between populations. Allele frequencies and forensic data for STRs were obtained from a sample of 384 unrelated individuals living in Bahia, Northeastern Brazil. Thus, the present study aimed to identify the allele frequency distribution, in addition to the forensic and genetic data, of 25 STR loci in the population of Bahia. Buccal swabs or fingertip punctures were utilized to amplify and detect 25 DNA markers. The most polymorphic loci were SE33 (43), D21S11, and FGA (21). The least polymorphic were TH01 (6), TPOX, and D3S1358 (7). Forensic and statistical data were obtained through data analysis, which revealed a large genetic diversity, with an average value of 0.813 for the analyzed population. The present study was more robust than previous STR marker studies and will contribute to future research on population genetics in Brazil and worldwide. The results of this study allowed the establishment of haplotypes found in the forensic samples of Bahia State to serve as a reference in the elucidation of criminal cases and paternity tests, as well as population and evolutionary investigations.

Temporal Changes in Gut Microbiota Composition and Pollen Diet Associated with Colony Weakness of a Stingless Bee.

Compared to honeybees and bumblebees, the effect of diet on the gut microbiome of Neotropical corbiculate bees such as Melipona spp. is largely unknown. These bees have been managed for centuries, but recently an annual disease is affecting M. quadrifasciata, an endangered species kept exclusively by management in Southern Brazil. Here we report the results of a longitudinal metabarcoding study involving the period of M. quadrifasciata colony weakness, designed to monitor the gut microbiota and diet changes preceding an outbreak. We found increasing amounts of bacteria associated to the gut of forager bees 2 months before the first symptoms have been recorded. Simultaneously, forager bees showed decreasing body weight. The accelerated growth of gut-associated bacteria was uneven among taxa, with Bifidobacteriaceae dominating, and Lactobacillaceae decreasing in relative abundance within the bacterial community. Dominant fungi such as Candida and Starmerella also decreased in numbers, and the stingless bee obligate symbiont Zygosaccharomyces showed the lowest relative abundance during the outbreak period. Such changes were associated with pronounced diet shifts, i.e., the rise of Eucalyptus spp. pollen amount in forager bees' guts. Furthermore, there was a negative correlation between the amount of Eucalyptus pollen in diets and the abundance of some bacterial taxa in the gut-associated microbiota. We conclude that diet and subsequent interactions with the gut microbiome are key environmental components of the annual disease and propose the use of diet supplementation as means to sustain the activity of stingless bee keeping as well as native bee pollination services.

The increase in SARS-CoV-2 lineages during 2020-2022 in a state in the Brazilian Northeast is associated with a number of cases.

SARS-CoV-2 has caused a high number of deaths in several countries. In Brazil, there were 37 million confirmed cases of COVID-19 and 700,000 deaths caused by the disease. The population size and heterogeneity of the Brazilian population should be considered in epidemiological surveillance due to the varied tropism of the virus. As such, municipalities and states must be factored in for their unique specificities, such as socioeconomic conditions and population distribution. Here, we investigate the spatiotemporal dispersion of emerging SARS-CoV-2 lineages and their dynamics in each microregion from Sergipe state, northeastern Brazil, in the first 3 years of the pandemic. We analyzed 586 genomes sequenced between March 2020 and November 2022 extracted from the GISAID database. Phylogenetic analyses were carried out for each data set to reconstruct evolutionary history. Finally, the existence of a correlation between the number of lineages and infection cases by SARS-CoV-2 was evaluated. Aracaju, the largest city in northeastern Brazil, had the highest number of samples sequenced. This represented 54.6% (320) of the genomes, and consequently, the largest number of lineages identified. Studies also analyzed the relationship between mean lineage distributions and mean monthly infections, daily cases, daily deaths, and hospitalizations of vaccinated and unvaccinated patients. For this, a correlation matrix was created. Results revealed that the increase in the average number of SARS-CoV-2 variants was related to the average number of SARS-CoV-2 cases in both unvaccinated and vaccinated individuals. Thus, our data indicate that it is necessary to maintain epidemiological surveillance, especially in capital cities, since they have a high rate of circulation of resident and non-resident inhabitants, which contributes to the dynamics of the virus.

Comparative genomics and phylogenomics of the Ralstonia solanacearum Moko ecotype and its symptomatological variants.

Banana tree bacterial wilt is caused by the Ralstonia solanacearum Moko ecotype. These strains vary in their symptom progression in banana, and are classified as typical Moko variants (phylotype IIA and IIB strains from across Central and South America), Bugtok variant (Philippines), and Sergipe facies (the states of Sergipe and Alagoas, Brazil). This study used comparative genomic and phylogenomic approaches to identify a correlation between the symptom progression of the Moko ecotypes based on the analysis of 23 available genomes. Average nucleotide identity and in silico DNA-DNA hybridization revealed a high correlation (>96% and >78%, respectively) between the genomes of Moko variants. Pan-genome analysis identified 21.3% of inheritable regions between representatives of the typical Moko and Sergipe facies variants, which could be traced to an abundance of exclusive homolog clusters. Moko ecotype genomes shared 1,951 orthologous genes, but representatives with typical symptoms did not display unique orthologues. Moreover, Bugtok disease and Sergipe facies genomes did not share any unique genes, suggesting convergent evolution to a shared symptom progression. Overall, genomic and phylogenomic analyses were insufficient to differentiate the Moko variants based on symptom progression.

Allelic frequencies distribution and forensic parameters of 23 autosomal short tandem repeats in the population of the State of Pernambuco, Brazil.

Located in the Northeast Region, the Pernambuco State is one of the 27 federative units of Brazil. Here, we determined populational data for 23 short tandem repeat (STR) markers - CSF1PO, FGA, TH01, TPOX, vWA, D1S1656, D2S1338, D2S441, D3S1358, D5S818, D7S820, D8S1179, D10S1248, D12S391, D13S317, D16S539, D18S51, D19S433, D21S11, D22S1045, PENTA D, PENTA E and SE33 - of the Pernambuco population. The sample consisted of 767 healthy, adult, unrelated individuals (437 males, 330 females) born and resident in the State of Pernambuco. STRs were amplified using three multiplex kits, according to the availability: PowerPlex® Fusion 6C System (Promega Corporation), PowerPlex® Fusion System (Promega Corporation) and GlobalFiler™ Express (Thermo Fisher Scientific). Allelic frequencies, forensic parameters and Hardy-Weinberg equilibrium determinations were estimated for all the 23 loci. No deviations from the Hardy-Weinberg equilibrium were observed for any of the markers, after Bonferroni correction. We observed that the most and less informative markers were SE33 and TPOX, respectively. The combined power of discrimination (CPD) was 0.99999999999999999999999999999, and the combined power of exclusion (CPE) was 0.99999999997. The cumulative typical paternity index was 37,919,301,869.3021. Interpopulation analyses (Nei's genetic distance) based on the expanded CODIS core loci was performed between the Pernambuco sample and other global populations. Pernambuco was the closest Brazilian population to African group and stayed distant from the Native American group. This work contributed to show that a panel of 23 autosomal STR loci is very informative, being able for forensic applications related in this population.

Fungal community diversity of heavy metal contaminated soils revealed by metagenomics.

The inappropriate disposal of toxic compounds generated by industrial activity has been impacting the environment considerably. Microbial communities inhabiting contaminated sites may represent interesting ecological alternatives for the decontamination of environments. The present work aimed to investigate the fungal diversity and its functionality contained in stream sediments with industrial waste contaminated with heavy metals by using metagenomic approach. A total of 12 fungal orders were retrieved from datasets and, at phylum level, Ascomycota was the most abundant, followed by Basidiomycota, Chytridiomycota and Blastocladiomycota. Higher abundance of sequences was encountered within the less contaminated site, while the lower abundance was found in the sample with the higher contamination with lead. Gene sequences related to DNA repair and heavy metals biosorption processes were found in the four samples analyzed. The genera Aspergillus and Chaetomium, and Saccharomycetales order were highly present within all samples, showing their potential to be used for bioremediation studies. The present work demonstrated the importance of using the metagenomic approach to understand the dynamics and the possible metabolic pathways associated with fungal communities related to environmental samples containing heavy metals, as well as evidenced the importance of improving culturomics techniques for isolating strains with potential application in bioremediation processes of environments contaminated with heavy metals.

Phytochemistry and Biological Activities of Amburana cearensis (Allemão) ACSm.

Amburana cearensis (Allemão) ACSm. belongs to the Fabaceae family and occurs in the Brazilian semiarid, Argentina, Paraguay, Bolivia, and Peru. Numerous studies that portray its ethnobotany, use in popular medicine, chemical composition, and biological activities exist in the literature. This review aimed to provide an overview of the chemical composition, ethnopharmacology, and biological activities associated with A. cearensis and its isolated constituents. Information was collected from internet searches in the Scopus, Medline, PubMed, Google Scholar, and ScienceDirect databases were performed covering publications from 1997-2020. An ethnopharmacological literature analysis revealed that A. cearensis is used to treat a wide range of respiratory disorders in addition to intestinal, circulatory, and inflammatory problems. Coumarins, flavonoids, phenolic glycosides, phenolic acids, phenylpropanoid derivatives, and triterpenoids, among others, have been reported as active compounds, with High-Performance Liquid Chromatography (HPLC) being the main analytical technique used. The A. cearensis extracts and compounds presented several biological activities, including antimicrobial, antinociceptive, anti-inflammatory, antioxidant, neuroprotective, and myorelaxant activities, among others. This review provides a useful bibliography for future investigations and A. cearensis applications; however, future studies should focus on its toxic effects and the mechanisms of action of its extracts and isolated constituents to guide clinical applications.

First Report of Xanthomonas citri subsp. citri causing Citrus Canker on lime in Rio Grande do Norte, Brazil.

Citrus canker caused by Xanthomonas citri subsp. citri is one of the most important citrus diseases in the world (Gottwald et al. 2002), mainly for citrus-producing countries with humid sub-tropical regions such as United States, Argentina, and Brazil, where losses may be significant (Behlau et al. 2020). In the state of Rio Grande do Norte (RN), Brazil, citrus production is expanding and shows social and economic importance for small farmers, which produced approximately 297 tons of lime in this state in 2019 (IBGE 2021). In December 2019, we observed symptoms of erumpent lesions with margins surrounded by yellow haloes on leaves and fruit of the lime (Citrus aurantifolia cv. 'Galego') (about 5% incidence) in a plantation located in the municipality of Mossoró, RN (05°12'21.1"S, 37°19'16"W). Samples were collected from the lime orchard, and five bacterial strains (CCRMXC01 to CCRMXC05) showing yellow, convex, mucoid colonies were isolated in a nutrient-yeast-dextrose-agar medium (NYDA). Pathogenicity tests were performed on sweet orange (C. sinensis cv. 'Pêra') and lime (C. latifolia cv. 'Tahiti') seedlings. Four wounds per leaf (upper side) were carried out with an entomological pin and 10 µl of a bacterial suspension (108 CFU mL-1) were deposited on each wound. The negative control consisted of leaves treated with sterile distilled water (SDW). For each citrus species, we used four replicates per strain and one leaf with four wounds per replicate. Inoculated leaves developed erumpent lesions with margins surrounded by yellow haloes six days after inoculation (DAI) in both citrus species, while leaves treated with SDW remained symptomless. Nine DAI, we reisolated the pathogen and performed rep-PCR (REP, ERIC, and BOX-PCR) analyses (Gama et al. 2018) with the strains inoculated and reisolated to confirm the identity of the strains and to fulfill Koch's postulates. The strains were stored at the Culture Collection Rosa Mariano (CCRM) of the Phytobacteriology Laboratory at the Universidade Federal Rural de Pernambuco. The five strains reisolated showed the same REP, ERIC, and BOX-PCR profiles as the strains used for inoculations. The molecular identification was performed sequencing the dnaK, fyuA, gyrB, and rpoD genes (Young et al. 2008). Each fragment was sequenced in both the forward and reverse directions. Using the BLASTn tool, we observed that sequences of the dnaK (GenBank MW218913 to MW218917), fyuA (GenBank MW218918 to MW218922), and rpoD (GenBank MW218928 to MW218932) genes of the strains CCRMXC01 to CCRMXC05 showed 100% of identity with the sequences of these genes from the type strain (ICMP 24T) and of other strains of X. citri subsp. citri (ICMP 21 and ICMP 7493), while sequences of gryB (GenBank MW218923 to MW218927) of the former strains showed 100% identity with the gyrB sequence of the strains ICMP 24T and ICMP 7493 and 99,85% identity with strain ICMP 21. This short variation in the sequence of the gyrB gene also may be observed among strains of X. citri subsp. citri available in NCBI database (https://www.ncbi.nlm.nih.gov/). The phylogenetic analysis performed using Bayesian inference and the concatenated sequence of all the type or representative strains of species and pathovars of Xanthomonas available in GenBank showed that the strains CCRMXC01 to CCRMXC05 clustered together with strain ICMP 24T with 1.0 posterior probability. To our information, this is the first report of X. citri subsp. citri causing citrus canker on lime in RN state, Brazil.

Effect of strength training on people with HIV and immunometabolic disorders / Efecto del entrenamiento de fuerza en personas con VIH y trastornos inmunometabólicos

The introduction of highly active antiretroviral therapy (HAART) was able to help to control viral condition in patients livingwith HIV/AIDS, diminishing virus concentration and increasing T CD4 + cells. However, adverse effects follow the treatment,like lipodystrophy syndrome, characterized by morphological changes in body fat distribution and changes serum lipids andglycides levels, increasing the risk for chronical diseases with cardiovascular effects. Thus, complimentary non-drug practices,as strength training, are essential to treat these patients, helping to improve their immunometabolic condition, leading to abetter coping with the disease. The aim of this study was to investigate the influence of a 12-week strength training protocolon immunometabolic system of people living with HIV/AIDS. It is a quasi-experimental study, conducted on 20 patients (16men), all living with HIV/AIDS using HAART. T CD4 + cell numbers, serum triglycerides, cholesterol (total and fractions) andglycemia were measured before and after training. The data underwent to descriptive statistics using a paired T test, withthe significance level set at p <0.05.There was a significant increase of 15.4% (p=0.009) on T CD4 + cells and, although notstatistically significant, reduction on glycemia, total cholesterol and triglycerides and increase on HDL-cholesterol fraction.So, it is suggested that strength training may be effective on immunometabolic condition of people living with HIV / AIDS,increasing T CD4+ cells and controlling serum levels of lipids and glycides.(AU)

La introducción de la terapia antirretroviral altamente activa (HAART) ayudó a controlar la condición viral de los pacientes con HIV/AIDS, reduciendo la concentración del virus y aumentando las células T CD4 +. Sin embargo, los efectos adversos acompañan el tratamiento, como el síndrome de lipodistrofia, caracterizada por cambios morfológicos en la distribución de la grasa corporal y de los niveles metabólicos en los lípidos y glicidos séricos, creciendo el riesgo de enfermedades crónicas con impacto cardiovascular. Así, los tratamientos complementarios no medicados, como el entrenamiento de fuerza, son esenciales en el tratamiento de estos pacientes, lo que contribuye en las mejoras inmunometabólicas en esta población, lo que contribuye a hacer frente a la enfermedad. El propósito de esta investigación fue verificar la influencia de un protocolode entrenamiento de fuerza con duración de 12 semanas en los sistemas inmunometabólicos de personas con HIV/SIDA.Este es un estudio cuasi-experimental, realizado con 20 pacientes (16 hombres), todos con HIV/SIDA usando la terapia HAART,sometidos a un protocolo de entrenamiento de fuerza de 12 semanas. Se tomaron medidas de las variables número de célulasT CD4 +, niveles séricos de triglicéridos, colesterol (total y fracciones) y glucosa en sangre, antes y después del entrenamiento.Los datos fueron analizados mediante estadística descriptiva, con prueba T pareada y nivel significativo establecido en p <0,05.El resultado mostró un aumento significativo en las células T CD4 + en un 15,4% (p=0,009), aunque no es estadísticamentesignificativo, tuve la glucosa en sangre reducida, así como el colesterol total y los triglicéridos, con respectivo aumento dela fracción de colesterol HDL. Por lo tanto, sugerimos que el entrenamiento de fuerza puede ser efectivo en las condicionesinmunológicas y metabólicas de las personas que viven con HIV/AIDS, aumentando las células T CD4 + y controlando los...(AU)

EntroPhylo: An entropy-based tool to select phylogenetic informative regions and primer design.

We present a novel entropy-based computational tool that selects phylogenetic informative genomic regions associated with degenerate primer design. This tool identifies proper phylogenetic markers and proposes suitable degenerate primers to amplify and sequence them. The algorithm calculates the entropy value per site, and the selected region is used for primer design. In order to evaluate the tool, sequences of bovine papillomavirus L1 gene were obtained. Once the molecular region was selected, the primers were designed by the software and used in a PCR reaction for viral detection. Three positive samples were tested with four different concentrations, and it was possible to detect the virus in all samples. The results show the applicability of a tool that can select informative regions for phylogenetic analysis and design primers to amplify and sequence these regions, becoming relevant for several studies focusing on pathogen detection, as well as phylogenetic and genetics studies of populations.

Genetic characteristics and phylogenetic analysis of Brazilian clinical strains of Pseudomonas aeruginosa harboring CRISPR/Cas systems.

The CRISPR-Cas are adaptive immune systems found in archaea and bacteria, responsible for providing sequence-specific resistance against foreign DNA. Strains of Pseudomonas aeruginosa may carry CRISPR/Cas system types I-F, I-E and/or I-C; however, several aspects related to the epidemiology and functionality of these systems have not yet been revealed. Here, we report 13 genomes of clinical strains of P. aeruginosa from Brazil that were positive for CRISPR/Cas system types I-F and I-E, a rare feature in this species. The phylogenetic tree, which was constructed with 161 other publicly available genomes, suggested no direct relationship between positive strains, and the various types of CRISPR/Cas systems were spread throughout the tree. Comparative analysis of the genetic locations of type I-F and a specific orphan CRISPR array (without cas genes), named the LES locus, showed sequence similarities between this orphan locus and type I-F, but these LES loci were inserted in a different genomic location. We also report the presence of prophages, the presence of anti-CRISPR genes, and possibly the presence of self-targeting spacers. Here, we conclude that CRISPR/Cas is highly associated with certain lineages and is spread throughout the phylogenetic tree, showing no clear pattern of evolutionary distribution. Moreover, the LES locus might be a CRISPR1 locus related to type I-F that may have been misplaced and maintained over time. Furthermore, strains carrying I-F and I-E are rare, and not all of them are closely related. Further functional work is needed to better comprehend if aspects reported in this study are functional, including the LES locus, self-targeting spacers, anti-CRISPR protection, and I-F/I-E-carrying lineages.

Genomic sequencing of different sequevars of Ralstonia solanacearum belonging to the Moko ecotype.

Banana vascular wilt or Moko is a disease caused by Ralstonia solanacearum. This study aimed to sequence, assemble, annotate, and compare the genomes of R. solanacearum Moko ecotypes of different sequevar strains from Brazil. Average nucleotide identity analyses demonstrated a high correlation (> 96%) between the genome sequences of strains CCRMRs277 (sequevar IIA-24), CCRMRs287 (IIB-4), CCRMRs304 (IIA-24), and CCRMRsB7 (IIB-25), which were grouped into phylotypes IIA and IIB. The number of coding sequences present in chromosomes and megaplasmids varied from 3,070 to 3,521 and 1,669 to 1,750, respectively. Pangenome analysis identified 3,378 clusters in the chromosomes, of which 2,604 were shared by all four analyzed genomes and 2,580 were single copies. In megaplasmids, 1,834 clusters were identified, of which 1,005 were shared by all four genomes and 992 were identified as single copies. Strains CCRMRsB7 and CCRMRs287 differed from the others by having unique clusters in both their chromosomes and megaplasmids, and CCRMRsB7 possessed the largest genome among all Moko ecotype strains sequenced to date. Therefore, the genomic information obtained in this study provides a theoretical basis for the identification, characterization, and phylogenetic analysis of R. solanacearum Moko ecotypes.

Genomic sequencing of two isolates of Ralstonia solanacearum causing Sergipe facies and comparative analysis with Bugtok disease isolates.

Ralstonia solanacearum is the causal agent of Moko disease in bananas, which in the state of Sergipe in northeastern Brazil causes "Sergipe facies". This disease induces atypical symptoms similar to those of Bugtok disease in the Philippines. This study was conducted to sequence, assemble, and annotate the genomes of the Sergipe facies-causing isolates SFC and IBSBF2570 (sequevar IIA-53) and compare their genomes with two representative isolates causing Bugtok disease. The genomes were sequenced and assembled, resulting in lengths of 5.58 Mb (SFC) and 5.46 Mb (IBSBF2570) in 185 and 174 contigs, respectively. The isolates of Sergipe facies and Bugtok disease showed similarities in their gene contents. We identified 5,668 information clusters, 3,752 of which were shared by all genomes (core genes). Moreover, 3,585 single-copy genes were identified. Isolates causing Bugtok disease exclusively shared 266 more information clusters than the isolates causing Sergipe facies. These results suggest that Sergipe facies and Bugtok disease isolates show high genomic similarity. However, the similarity is even greater between the Bugtok disease isolates. This may be because of their longer period of interaction compared to Sergipe facies isolates.

Helicobacter pylori cagE, cagG, and cagM can be a prognostic marker for intestinal and diffuse gastric cancer.

It is known that Helicobacter pylori is the main cause of peptic ulceration and gastric cancer. However, there is a lack of information on whether H. pylori strains may differ in gastric cancer histological subtypes. This study aimed to investigate different H. pylori strains considering six cag Pathogenicity Island - cagPAI genes (cagA, cagE, cagG, cagM, cagT, and virb11), and vacuolating cytotoxin - vacA alleles, and their relation to gastric cancer histologic subtypes. For this purpose, tumor samples from 285 patients with gastric carcinoma were used. H. pylori infection and genotypes were determined by polymerase chain reaction (PCR). H. pylori was detected in 93.9% of gastric tumors. For comparative analyzes between histopathological subtypes considering H. pylori cagPAI genes the strains were grouped according to the vacA s1/s2 alleles. In the vacAs1 group, the strains cagA(-)cagE(+), cagA(+)cagE(+)cagG(+), cagA(+)cagM(+), or only cagE(+) strains were more frequent in the intestinal subtype (P = .009; P = .024; P = .046, respectively). In contrast, cagM(+)cagG(+)cagA(-) and cagE(-) were associated with diffuse tumors (P = .036), highlighting the presence of cagE in the development of intestinal tumors, and the presence of cagG and absence of cagE in diffuse tumors. Furthermore, WEKA software and Decision Tree (CART) analyses confirmed these findings, in which cagE presence was associated with intestinal tumors, and cagE absence and cagG(+) with diffuse tumors. In conclusion our results showed that vacAs1 (cagG + cagM) strains, mainly cagG positive with cagE absence, were relevant in the studied population for the diffuse outcome, while the presence of cagE was relevant for the intestinal outcome. These findings suggest the relevance of these H. pylori genes as potential markers for gastric cancer histological outcomes.

Application of next generation sequencing (NGS) for descriptive analysis of 30 genomes of Leishmania infantum isolates in Middle-North Brazil.

Visceral leishmaniasis (VL) is a life-threatening disease caused by the protozoa Leishmania donovani and L. infantum. Likely, L. infantum was introduced in the New World by the Iberic colonizers. Due to recent introduction, the genetic diversity is low. Access to genomic information through the sequencing of Leishmania isolates allows the characterization of populations through the identification and analysis of variations. Population structure information may reveal important data on disease dynamics. Aiming to describe the genetic diversity of L. infantum from the Middle-North, Brazil, next generation sequencing of 30 Leishmania isolates obtained in the city of Teresina, from where the disease dispersed, was performed. The variations were categorized accordingly to the genome region and impact and provided the basis for chromosomal ploidy and population structure analysis. The results showed low diversity between the isolates and the Iberic reference genome JPCM5. Most variations were seen in non-coding regions, with modifying impact. The ploidy number analysis showed aneuploid profile. The population structure analysis revealed the presence of two L. infantum populations identified in Teresina. Further population genetics studies with a larger number of isolates should be performed in order to identify the genetic background associated with virulence and parasite ecology.

Effect of Vitamin K3 Inhibiting the Function of NorA Efflux Pump and Its Gene Expression on Staphylococcus aureus.

Resistance to antibiotics has made diseases that previously healed easily become more difficult to treat. Staphylococcus aureus is an important cause of hospital-acquired infections and multi-drug resistant. NorA efflux pump, present in bacteria S. aureus, is synthesized by the expression of the norA gene. Menadione, also known as vitamin K3, is one of the synthetic forms of vitamin K. Therefore, the aim of this study is to verify the menadione effect on efflux inhibition through NorA pump gene expression inhibition and assess the effects of menadione in bacterial membrane. The effect of menadione as an efflux pump inhibitor (EPI) was evaluated by the microdilution method, fluorimetry, electron microscopy, and by RT-qPCR to evaluate gene expression. In the molecular docking, association with menadione induces increased fluorescence intensity. Menadione was observed (100% of the clusters) interacting with residues ILE12, ILE15, PHE16, ILE19, PHE47, GLN51, ALA105, and MET109 from NorA. The results showed the norA gene had its expression significantly diminished in the presence of menadione. The simulation showed that several menadione molecules were able to go through the bilayer and allow the entry of water molecules into the hydrophobic regions of the bilayer. When present within membranes, menadione may have caused membrane structural changes resulting in a decline of the signaling pathways involved in norA expression. Menadione demonstrated to be an efflux pump inhibitor with dual mechanism: affecting the efflux pump by direct interaction with protein NorA and indirectly inhibiting the norA gene expression, possibly by affecting regulators present in the membrane altered by menadione.