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Several mycobacterial species are known to cause human diseases, such as tuberculosis and leprosy. In addition to these pathogenic species, there are also saprophytic representatives, which occasionally cause opportunistic infections. It is well established that numerous mycobacteria produce biofilms containing cellulose, and their genomes frequently harbor genes involved in cellulose degradation, such as celA1. Notably, the BCG Moreau vaccine strain carries a specific deletion of two-base pairs, resulting in a predicted protein with fewer than 100 amino acids in the catalytic portion at the C-terminal end. We investigated the functional consequences of this polymorphism and observed that recombinant enzyme from the Moreau strain lack catalytic activity. Furthermore, compared to the Pasteur strain, Moreau is unable to utilize carboxymethylcellulose (CMC) as the sole carbon source. These findings suggest an absence of cellulolytic activity in this strain, which may influence the bacterium virulence., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: The Bacille Calmette-Guérin (BCG) vaccine comprises a family of strains with variable protective efficacy against pulmonary tuberculosis (TB) and leprosy, partly due to genetic differences between strains., Objectives: Previous data highlighting differences between the genomes and proteomic profiles of BCG strains Moreau and Pasteur led us to evaluate their behaviour in the macrophage microenvironment, capable of stimulating molecular responses that can impact the protective effect of the vaccine., Methods: Strain infectivity, viability, co-localisation with acidified vesicles, macrophage secretion of IL-1 and MCP-1 and lipid droplet biogenesis were evaluated after infection., Findings: We found that BCG Moreau is internalised more efficiently, with significantly better intracellular survival up to 96 h p.i., whereas more BCG Pasteur bacilli were found co-localised in acidified vesicles up to 6 h p.i. IL-1β and MCP-1 secretion and lipid droplet biogenesis by infected macrophages were more prominent in response to BCG Pasteur., Main Conclusion: Overall, our results show that, compared to Pasteur, BCG Moreau has increased fitness and better endurance in the harsh intracellular environment, also regulating anti-microbial responses (lower IL-1b and MCP-1). These findings contribute to the understanding of the physiology of BCG Moreau and Pasteur in response to the intraphagosomal environment in a THP-1 macrophage model.

Mycobacterium bovis BCG Moreau is the main Brazilian strain for vaccination against tuberculosis. It is considered an early strain, more like the original BCG, whereas BCG Pasteur, largely used as a reference, belongs to the late strain clade. BCG Moreau, contrary to Pasteur, is naturally deficient in homologous recombination (HR). In this work, using a UV exposure test, we aimed to detect differences in the survival of various BCG strains after DNA damage. Transcription of core and regulatory HR genes was further analyzed using RT-qPCR, aiming to identify the molecular agent responsible for this phenotype. We show that early strains share the Moreau low survival rate after UV exposure, whereas late strains mimic the Pasteur phenotype, indicating that this increase in HR efficiency is linked to the evolutionary clade history. Additionally, RT-qPCR shows that BCG Moreau has an overall lower level of these transcripts than Pasteur, indicating a correlation between this gene expression profile and HR efficiency. Further assays should be performed to fully identify the molecular mechanism that may explain this differential phenotype between early and late BCG strains.

Mycobacterium bovis BCG is the only vaccine against tuberculosis. The variable forms of cultivation throughout the years, before seed-lots were developed, allowed in vitro evolution of the original strain, generating a family of vaccines with different phenotypic and genotypic characteristics. Molecular studies revealed regions of difference (RDs) in the genomes of the various BCG strains. This work aims to characterize the gene pair rv3407-rv3408 ( vapB47 - vapC47 ), coding for a toxin-antitoxin system of the VapBC family, and to evaluate possible transcriptional effects due to the adjacent BCG Moreau-specific genomic deletion RD16. We show that these genes are co-transcribed in BCG strains Moreau and Pasteur, and that the inactivation of an upstream transcriptional repressor (Rv3405c) due to RD16 has a polar effect, leading to increased vapBC47 expression. Furthermore, we detect VapB47 DNA binding in vitro, dependent on a 5' vapB47 sequence that contributes to a palindrome, spanning the promoter and coding region. Our data shed light on the regulation of VapBC systems and on the impact of the BCG Moreau RD16 deletion in the expression of adjacent genes, contributing to a better understanding of BCG Moreau physiology.

Tuberculosis is a world widespread disease, caused by Mycobacterium tuberculosis ( M.tb ). Although considered an obligate aerobe, this organism can resist life-limiting conditions such as microaerophily mainly due to its set of enzymes responsible for energy production and coenzyme restoration under these conditions. One of these enzymes is fumarate reductase, an heterotetrameric complex composed of a catalytic (FrdA), an iron-sulfur cluster (FrdB) and two transmembrane (FrdC and FrdD) subunits involved in anaerobic respiration and important for the maintenance of membrane potential. In this work, aiming to further characterize this enzyme function in mycobacteria, we analyzed the expression of FrdB-containing proteins in M.tb and Mycobacterium bovis Bacillus Calmette-Guérin (BCG) Moreau, the Brazilian vaccine strain against tuberculosis. We identified three isoforms in both mycobacteria, two of them corresponding to the predicted encoded polypeptides of M.tb (27 kDa) and BCG Moreau (40 kDa) frd sequences, as due to an insertion on the latter's operon a fused FrdBC protein is expected. The third 52 kDa band can be explained by a transcriptional slippage event, typically occurring when mutation arises in a repetitive region within a coding sequence, thought to reduce its impact allowing the production of both native and variant forms. Comparative modeling of the M.tb and BCG Moreau predicted protein complexes allowed the detection of subtle overall differences, showing a high degree of structure and maybe functional resemblance among them. Axenic growth and macrophage infection assays show that the frd locus is important for proper bacterial development in both scenarios, and that both M.tb 's and BCG Moreau's alleles can partially revert the hampered phenotype of the knockout strain. Altogether, our results show that the frdABCD operon of Mycobacteria may have evolved to possess other yet non-described functions, such as those necessary during aerobic logarithmic growth and early stage steps of infection., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Schwarz, Antunes, Corrêa, Silva-Gonçalves, Malaga, Caffarena, Guilhot and Mendonça-Lima.)

Background: Lutzomyia longipalpis-derived cell line (Lulo) has been suggested as a model for studies of interaction between sandflies and Leishmania., Objectives: Here, we present data of proteomic and gene expression analyses of Lulo cell related to interactions with Leishmania (Viannia) braziliensis., Methods: Lulo cell protein extracts were analysed through a combination of two-dimensional gel electrophoresis and mass spectrometry and resulting spots were further investigated in silico to identify proteins using Mascot search and, afterwards, resulting sequences were applied for analysis with VectorBase., Results: Sixty-four spots were identified showing similarities to other proteins registered in the databases and could be classified according to their biological function, such as ion-binding proteins (23%), proteases (14%), cytoskeletal proteins (11%) and interactive membrane proteins (9.5%). Effects of interaction with L. (V.) braziliensis with the expression of three genes (enolase, tubulin and vacuolar transport protein) were observed after an eight-hour timeframe and compared to culture without parasites, and demonstrated the impact of parasite interaction with the expression of the following genes: LLOJ000219 (1.69-fold), LLOJ000326 (1.43-fold) and LLOJ006663 (2.41-fold)., Conclusions: This set of results adds relevant information regarding the usefulness of the Lulo cell line for studies with Leishmania parasites that indicate variations of protein expression.

The ability to perform genetic manipulation of mycobacteria is important for characterization of gene function. Homologous recombination-based protocols are frequently used for reverse genetics studies with mycobacteria. It is known that Mycobacteriumbovis BCG Russia, closely related to M. bovis BCG Moreau, is a natural recA deficient strain and is non-permissive to homologous recombination assays. In this work we show that M. bovis BCG Moreau is also deficient in homologous recombination, shown by a specialized transduction assay, but this phenotype can be reverted by complementation with heterologous recombinases, using a recombineering protocol. Sequence analysis of the genes known to be involved in homologous recombination annotated in the genome of BCG Moreau detected no differences compared to the genome of BCG Pasteur. Further studies are needed in order to determine the exact mechanism underlying this deficiency in BCG Moreau., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Surface-associated proteins from Mycobacterium bovis BCG Moreau RDJ are important components of the live Brazilian vaccine against tuberculosis. They are important targets during initial BCG vaccine stimulation and modulation of the host's immune response, especially in the bacterial-host interaction. These proteins might also be involved in cellular communication, chemical response to the environment, pathogenesis processes through mobility, colonization, and adherence to the host cell, therefore performing multiple functions. In this study, the proteomic profile of the surface-associated proteins from M. bovis BCG Moreau was compared to the BCG Pasteur reference strain. The methodology used was 2DE gel electrophoresis combined with mass spectrometry techniques (MALDI-TOF/TOF), leading to the identification of 115 proteins. Of these, 24 proteins showed differential expression between the two BCG strains. Furthermore, 27 proteins previously described as displaying moonlighting function were identified, 8 of these proteins showed variation in abundance comparing BCG Moreau to Pasteur and 2 of them presented two different domain hits. Moonlighting proteins are multifunctional proteins in which two or more biological functions are fulfilled by a single polypeptide chain. Therefore, the identification of such proteins with moonlighting predicted functions can contribute to a better understanding of the molecular mechanisms unleashed by live BCG Moreau RDJ vaccine components.

We report a case of Tinea nigra in an adolescent living in Itapema, Santa Catarina, Brazil, who presented a hyperchromic macule on the palm of the left hand, close to another erythematous macule caused by a rabbit bite. The patient received guidance on accidents and animal bites and evolved well treated with topical butenafine for the dermatomycosis. The authors also highlight the efficacy of the dermoscopic exam in diagnosing Tinea nigra with animal bite lesions and other traumas.

Gene expression in Trypanosoma cruzi is regulated at the post-transcriptional level and cis-acting elements present in the 3' untranslated region (3'UTR) play an important role by interacting with regulatory proteins. Previous studies demonstrated that the GP82 surface glycoprotein, which is involved in host cell invasion, is up-regulated in the infective metacyclic trypomastigote form, and that GP82 mRNA half-life is longer in this form compared to the non-infective epimastigote form. Here, we demonstrate that the 3'UTR of the GP82 transcript is involved in this developmental regulation, promoting higher expression of the green fluorescent protein (GFP) reporter in metacyclic trypomastigotes than in epimastigotes. A series of stepwise deletions in the 3'UTR was created and results suggest that the mechanism regulating GP82 expression involves multiple elements in the 3'UTR., (Copyright © 2012 Elsevier B.V. All rights reserved.)

We report here for the first time the in vitro effects of (1S,2R,4S)-1,7,7-trimethyl-bicyclo[2·2·1]heptan-2-yl-3',4',5'-trimethoxy benzoate (1) and (1S,2R,4S)-1,7,7-trimethyl-bicyclo[2·2·1]heptan-2-yl benzoate (2) on the growth and ultrastructure of Trypanosoma cruzi. These two synthetic compounds exerted an antiproliferative effect on the epimastigote forms of the parasite. The ICs(50/72h) of two synthetic L-bornyl benzoates, 1 and 2, was 10·1 and 12·8 μg/ml, respectively. Both compounds were more selective against epimastigotes than HEp-2 cells. Ultrastructural analysis revealed intense cytoplasmic vacuolization and the appearance of cytoplasmic materials surrounded by membranes. The treatment of peritoneal macrophages with compounds 1 and 2 caused a significant decrease in the number of T. cruzi-infected cells. L-Bornyl benzoate derivatives may serve as a potential source for the development of more effective and safer chemotherapeutic agents against T. cruzi infections.

Background: heart rate variability (HRV) is a noninvasive diagnostic method used in the assessment of the autonomic modulation of the heart. The assessment of HRV using nonlinear dynamics methods in the preoperative period of surgical myocardial revascularization could be predictive of morbidity such as pulmonary infections in the postoperative period., Objective: to evaluate the behavior of HRV using nonlinear dynamics in the preoperative period of surgical myocardial revascularization and its relation to the occurrence of pulmonary infections in the in-hospital postoperative period., Methods: a total of 69 patients with coronary artery disease (mean age of 58.6 ± 10.4 years) and indication for elective surgical myocardial revascularization were studied. In order to quantify the nonlinear dynamics of HRV, the following procedures were performed: detrended fluctuation analysis (DFA); analysis of the short (α1) and long-term (α2) components of DFA; approximate entropy (ApEn); Lyapunov exponent (LE); and Hurst exponent (HE) of time series of RR intervals of the ECG, as captured by the Polar S810i instrument on the day before surgery., Results: at the cut-off levels set by the ROC curve, there was a significant difference between the groups with and without pulmonary infections in the postoperative period of myocardial revascularization for total DFA, approximate entropy and Lyapunov exponent with p = 0. 0309, p = 0.0307 and p = 0.0006, respectively., Conclusion: the nonlinear dynamics methods, at their respective cut-off levels, allowed for the identification of patients developing pulmonary infection in the postoperative period of surgical myocardial revascularization, thus suggesting that these methods may have a prognostic value for this group of patients.

The genus Phytomonas comprises trypanosomatids that can parasitize a broad range of plant species. These flagellates can cause diseases in some plant families with a wide geographic distribution, which can result in great economic losses. We have demonstrated previously that Phytomonas serpens 15T, a tomato trypanosomatid, shares antigens with Trypanosoma cruzi, the agent of human Chagas disease. Herein, two-dimensional gel electrophoresis (2-DE) and mass spectrometry (MS) were used to identify proteins of P. serpens 15T that are recognized by sera from patients with Chagas disease. After 2D-electrophoresis of whole-cell lysates, 31 peptides were selected and analyzed by tandem mass spectrometry. Twenty-eight polypeptides were identified, resulting in 22 different putative proteins. The identified proteins were classified into 8 groups according to biological process, most of which were clustered into a cellular metabolic process category. These results generated a collection of proteins that can provide a starting point to obtain insights into antigenic cross reactivity among trypanosomatids and to explore P. serpens antigens as candidates for vaccine and immunologic diagnosis studies.

Objectives: To identify clinical characteristics indicative of dengue and to evaluate the applicability to children of the Health Ministry criteria for suspected cases., Methods: A cross-sectional study undertaken at the General Pediatrics Center of the Fundação Hospitalar de Minas Gerais. Children were enrolled if presenting acute febrile conditions with no definite etiology, lasting > 24 hours and < or = 7 days and if resident in the Metropolitan Region of Belo Horizonte. Clinical variables were investigated, specific tests were performed and aspartate-aminotransferase assayed, during a period considered both endemic and epidemic for the disease. The subset of children who did have dengue was compared with the subset of nonspecific acute febrile diseases. The Health Ministry criteria for suspected cases was evaluated., Results: Dengue was diagnosed in 50.4% of the 117 children studied. There were no statistically significant associations between the disease and the majority of the symptoms analyzed. Only exanthema was more often associated with dengue (Prevalence Ratio = 1.49; 95% CI: 1.05-2.11). The criteria for suspected cases of dengue had a sensitivity of just 50.8% and a positive predictive value of 62.5%. These values were greater among schoolchildren and during the period of greater disease incidence., Conclusions: Dengue is common among febrile diseases of childhood, with prevalence that varies according to the epidemiological situation. The clinical status of children with dengue was very similar to that of children with other nonspecific diseases. The Health Ministry criteria for suspected cases was shown to be of little use, particularly with smaller children and during periods of reduced incidence.

Objective: To assess the association between the proportion of buildings positive for Aedes aegypti larvae measured by means of building infestation rate and dengue incidence rate., Methods: Autochthonous dengue cases were selected and building infestation rates assessed in the coverage areas of health districts in the city of Belo Horizonte, Brazil, from October 1997 to May 2001. After grouping building infestation rates according to their distribution in quartiles, mean dengue incidence rates (for the month following the building infestation assessment) were compared using ANOVA., Results: A weak though statistically significant correlation was observed between monthly dengue incidence and building infestation rates for the health districts (r=0.21; p=0.02) and coverage areas (r=0.14; p=0.00) in the study period. After grouping building infestation rates in quartiles, coverage areas of building infestation between 0.46% and 1.32% (second quartile) showed a mean monthly dengue incidence rate twice as high as areas of building infestation lower or equal to 0.45% (first quartile). Areas of building infestation between 1.33% and 2.76% (third quartile) and equal to or higher than 2.77% had a mean monthly dengue incidence rate five and seven times, respectively, higher than those areas showing 0.45% or less., Conclusions: Despite the well-known limitations of building infestation rates for estimating vector infestation and prediction of dengue epidemics, the study results indicate that higher building infestation rates were associated to a higher risk of disease transmission in the health districts and coverage areas of Belo Horizonte.

Background: Although no regimen can eradicate in 100% of patients, factors that may affect the eradication rates have been poorly studied., Goal: To evaluate factors associated with treatment failure., Study: One hundred patients were treated with pantoprazole plus clarithromycin and furazolidone for eradication. Clarithromycin and furazolidone resistance was evaluated by the agar dilution method. Point mutations in 23S rRNA genes related to clarithromycin resistance were investigated by polymerase chain reaction and restriction length fragment polymorphism and A by polymerase chain reaction. The data were analyzed by logistic regression., Results: eradication occurred in 85 of 97 patients who completed the treatment (87.6%; 95% CI = 79.0-93.1). All strains were susceptible to furazolidone, and nine were resistant to clarithromycin (A2142G or A2143G mutation was detected in all of them). The treatment failure was significant and independently associated with clarithromycin resistance (OR = 7.79; 95% CI = 1.73-35.01), A-negative status (OR = 4.81; 95% CI = 1.14-20.14), and male gender (OR = 4.20; 95% CI = 1.01-17.78), but not with the type of disease, mean age, smoking, alcohol consumption, and the degree of the antral and oxyntic gastritis., Conclusion: Resistance to clarithromycin, A-negative status, and gender were predictive factors of eradication failure.

Helicobacter pylori resistance to metronidazole was detected in 107 (52.97%) of 202 strains. Twenty (9.85%) strains, 18 of them harboring 23S ribosomal DNA mutations, were resistant to clarithromycin. Metronidazole resistance was associated with female gender. Resistance to metronidazole and resistance to clarithromycin were associated. Increasing clarithromycin resistance rates were observed over time.