Ecology shapes the genomic and biosynthetic diversification of Streptomyces bacteria from insectivorous bats.

Streptomyces are prolific producers of secondary metabolites from which many clinically useful compounds have been derived. They inhabit diverse habitats but have rarely been reported in vertebrates. Here, we aim to determine to what extent the ecological source (bat host species and cave sites) influence the genomic and biosynthetic diversity of Streptomyces bacteria. We analysed draft genomes of 132 Streptomyces isolates sampled from 11 species of insectivorous bats from six cave sites in Arizona and New Mexico, USA. We delineated 55 species based on the genome-wide average nucleotide identity and core genome phylogenetic tree. Streptomyces isolates that colonize the same bat species or inhabit the same site exhibit greater overall genomic similarity than they do with Streptomyces from other bat species or sites. However, when considering biosynthetic gene clusters (BGCs) alone, BGC distribution is not structured by the ecological or geographical source of the Streptomyces that carry them. Each genome carried between 19-65 BGCs (median=42.5) and varied even among members of the same Streptomyces species. Nine major classes of BGCs were detected in ten of the 11 bat species and in all sites: terpene, non-ribosomal peptide synthetase, polyketide synthase, siderophore, RiPP-like, butyrolactone, lanthipeptide, ectoine, melanin. Finally, Streptomyces genomes carry multiple hybrid BGCs consisting of signature domains from two to seven distinct BGC classes. Taken together, our results bring critical insights to understanding Streptomyces-bat ecology and BGC diversity that may contribute to bat health and in augmenting current efforts in natural product discovery, especially from underexplored or overlooked environments.

Heavy Metal Tolerance of Microorganisms Isolated from Coastal Marine Sediments and Their Lead Removal Potential.

In this study, 338 microorganisms, comprising 271 bacteria and 67 fungi, were isolated from sediment samples collected from underexplored Pacific and Caribbean regions of Colombia. Screening trials were conducted on selected strains (n = 276) to assess their tolerance to cadmium (Cd2+), lead (Pb2+), and zinc (Zn2+), leading to the identification of six bacteria capable of withstanding 750 mg·L-1 of each heavy metal ion. Three promising microorganisms, identified as Enterobacter sp. INV PRT213, Pseudomonas sp. INV PRT215, and Stenotrophomonas sp. INV PRT216 were selected for lead removal experiments using LB broth medium supplemented with 400 mg·L-1 Pb2+. Among these, Pseudomonas sp. INV PRT215 exhibited significant potential, removing 49% of initial Pb2+ after 240 min of exposure (16.7 g wet biomass·L-1, pH 5, 30 °C). Infrared spectra of Pb-exposed biomass showed changes in functional groups, including carbonyl groups of amides, carboxylate, phosphate, hydroxyl, and amine groups, compared to the not-exposed control. These changes suggested interactions between the metal and functional groups in the biomass. The findings of this study highlight the potential of microorganisms derived from coastal marine environments as promising candidates for future applications in bioremediation of polluted environments contaminated with heavy metals.

Effect of the variation in the extracellular concentration of l-arginine in the physiology of Leishmania (Viannia) braziliensis and its susceptibility to some antileishmanial drugs.

The knowledge about amino acid metabolism in trypanosomatids is a valuable source of new therapeutic targets. l-arginine is an essential amino acid for Leishmania parasites, and it participates in the synthesis of polyamines, a group of essential nutrients used for nucleic acids, proteins biosynthesis, and redox modulation necessary for proliferation. In the present study, we evaluated the effect of changes in the availability of this amino acid on promastigotes and intracellular amastigotes on U937 macrophages and showed that the absence of l-arginine in culture medium negatively influences the growth and infectivity of Leishmania (Viannia) braziliensis, causing a decrease in the percentage of the infected cells and parasite load tested through light microscopy. In addition, the absence of l-arginine resulted in the parasite's inability to regulate its reactive oxygen species (ROS) production, which persisted for up to 24 h by flow cytometry following the probe H2DCF-DA dye. Moreover, the differentiation of promastigote to amastigote in axenic culture was more significant at low concentrations of l-arginine suggesting that this depletion induces a stress environment to increase this transformation under axenic conditions. No association was established between the availability of l-arginine and the effectiveness of antileishmanial drugs. All these results confirm the importance of l-arginine in L. braziliensis life cycle vital processes, such as its replication and infectivity, as documented in other Leishmania species. Based on these results, we proposed that the l-arginine uptake/metabolism route is possible in exploring new antileishmanial drugs.

Enfermedad renal crónica de las comunidades agrícolas, una revisión de la literatura / Chronic Kidney Disease in Agricultural Communities, review of the literature

Resumen La enfermedad renal crónica (ERC) se define como la alteración funcional o estructural progresiva de los riñones que persiste por 3 meses o más. Esta enfermedad afecta el 10 al 15 % de la población mundial, siendo la diabetes mellitus, la hipertensión arterial, las glomerulopatías primarias y las enfermedades genéticas las etiologías más frecuentemente asociadas. Sin embargo, en los países pobres se reportan otras enfermedades causantes de la ERC; entre ellas la nefropatía mesoamericana (NM). La NM se presenta principalmente en la población masculina joven, lo cual lleva a pérdida de la vida laboral productiva. En Colombia hay una alta prevalencia de ERC con etiología no estudiada (mal llamada desconocida) y hay pocas investigaciones de la ERC en las comunidades agrícolas. Teniendo en cuenta que la población campesina de Colombia se expone a noxas climáticas y laborales similares a Mesoamérica, es posible que esta nefropatía también sea una causa de ERC en nuestra población. El presente artículo hace una revisión de la ERC de las comunidades agrícolas, con el fin de sensibilizar el personal de salud en la importancia de la búsqueda de esta enfermedad en la población vulnerable, lo cual podría impactar de una forma positiva en la salud de los agricultores y campesinos.

Summary Chronic kidney disease (CKD) is defined as an abnormality of the kidney structure or function for ≥ 3 months. This disease affects 10% to 15% of the world's population, with diabetes, arterial hypertension, primary glomerulopathies and genetic disorders being the most common etiologies associated with this disease worldwide. Nevertheless, in low-income countries, other diseases causing CKD are also reported; among them, Mesoamerican nephropathy, which is a common cause of CKD in Mesoamerica, especially in the young male population, leading to loss of productive working capacity. In Colombia, the prevalence of CKD with unknown etiology is high and there are few studies on chronic kidney disease in agricultural communities, given that the agricultural population in Colombia is exposed to harmful climatic and occupational agents similar to those in Mesoamerica, it is possible that this nephropathy is also a cause of CKD in our population. This article provides an overview of CKD in agricultural communities to sensitize health workers to the importance of screening for this disease in vulnerable populations, which could have a positive impact on the health of farmers.

Diversity of cultivable bacteria from deep-sea sediments of the Colombian Caribbean and their potential in bioremediation.

The diversity of deep-sea cultivable bacteria was studied in seven sediment samples of the Colombian Caribbean. Three hundred and fifty two marine bacteria were isolated according to its distinct morphological character on the solid media, then DNA sequences of the 16S rRNA were amplified to identify the isolated strains. The identified bacterial were arranged in three phylogenetic groups, Firmicutes, Proteobacteria, and Actinobacteria, with 34 different OTUs defined at ≥ 97% of similarity and 70 OTUs at ≥ 98.65%, being the 51% Firmicutes, 34% Proteobacteria and 15% Actinobacteria. Bacillus and Fictibacillus were the dominant genera in Firmicutes, Halomonas and Pseudomonas in Proteobacteria and Streptomyces and Micromonospora in Actinobacteria. In addition, the strains were tested for biosurfactants and lipolytic enzymes production, with 120 biosurfactant producing strains (mainly Firmicutes) and, 56 lipolytic enzymes producing strains (Proteobacteria). This report contributes to the understanding of the diversity of the marine deep-sea cultivable bacteria from the Colombian Caribbean, and their potential application as bioremediation agents.

Dereplication of antimicrobial biosurfactants from marine bacteria using molecular networking.

Biosurfactants are amphiphilic surface-active molecules of microbial origin principally produced by hydrocarbon-degrading bacteria; in addition to the bioremediation properties, they can also present antimicrobial activity. The present study highlights the chemical characterization and the antimicrobial activities of biosurfactants produced by deep-sea marine bacteria from the genera Halomonas, Bacillus, Streptomyces, and Pseudomonas. The biosurfactants were extracted and chemically characterized through Chromatography TLC, FT-IR, LC/ESI-MS/MS, and a metabolic analysis was done through molecular networking. Six biosurfactants were identified by dereplication tools from GNPS and some surfactin isoforms were identified by molecular networking. The half-maximal inhibitory concentration (IC50) of biosurfactant from Halomonas sp. INV PRT125 (7.27 mg L-1) and Halomonas sp. INV PRT124 (8.92 mg L-1) were most effective against the pathogenic yeast Candida albicans ATCC 10231. For Methicillin-resistant Staphylococcus aureus ATCC 43300, the biosurfactant from Bacillus sp. INV FIR48 was the most effective with IC50 values of 25.65 mg L-1 and 21.54 mg L-1 for C. albicans, without hemolytic effect (< 1%), and non-ecotoxic effect in brine shrimp larvae (Artemia franciscana), with values under 150 mg L-1, being a biosurfactant promising for further study. The extreme environments as deep-sea can be an important source for the isolation of new biosurfactants-producing microorganisms with environmental and pharmaceutical use.

Nasal Provocation Test with Cat and Dog Extracts: Results according to Molecular Components.

BACKGROUND: IgE sensitization (atopy) to pets is commonly evaluated using pet dander extracts. However, the diagnosis by components seems to be more adequate to evaluate the clinical relevance (allergy) of sIgE sensitization. OBJECTIVE: To study the association between IgE sensitization to pet allergen components and clinical symptoms. Methodology. Dander extracts and sIgE levels to pet components (Can f 1, Can f 2, Can f 3, Can f 5, Fel d 1, Fel 2, and Fel 4) were measured in a rhinitis group (n = 101) and a control group (n = 101) and a control group (. RESULTS: Dog (34.6% vs. 23.5%) and cat dander (26.7% vs. 8.8%, p = 0.05) IgE sensitization was frequent among rhinitis and no-rhinitis subjects, and it was similar to dog (29.7% vs. 20.5%) and cat (18.8% vs. 8.8%) components. Polysensitization for dog (3.1, 95% CI: 1.5 to 6.1, p = 0.05) IgE sensitization was frequent among rhinitis and no-rhinitis subjects, and it was similar to dog (29.7% vs. 20.5%) and cat (18.8% vs. 8.8%) components. Polysensitization for dog (3.1, 95% CI: 1.5 to 6.1, p = 0.05) IgE sensitization was frequent among rhinitis and no-rhinitis subjects, and it was similar to dog (29.7% vs. 20.5%) and cat (18.8% vs. 8.8%) components. Polysensitization for dog (3.1, 95% CI: 1.5 to 6.1. CONCLUSIONS: Sensitization to pet dander extract identifies atopic patients, but its utility to predict clinical relevance is poor. Allergenic components could help to define the clinical relevance of sensitization to furry animals and could reduce the need for provocation test.

Secuestro pulmonar en adultos: reporte de tres casos y revisión de la literatura / Adult bronchopulmonary sequestration: report of three cases and review of the literature

Resumen El secuestro pulmonar es una enfermedad congénita infrecuente caracterizada por la presencia de una porción de parénquima pulmonar que recibe vascularización independiente de la circulación sistémica. Se presentan tres casos de secuestro pulmonar intralobares, de presentación tardía, uno de ellos asociado a una malformación adenomatosa quística y en los cuales el manejo se completó por videotoracoscopia: dos de ellos con lobectomía total y uno con lobectomía sublobar. Se trata de una enfermedad de presentación clínica variable y cuyo tratamiento es, en la mayoría de los casos, quirúrgico, requiriéndose usualmente resecciones lobares, las cuales pueden llevarse a cabo de manera eficaz y segura por videotoracoscopia.

Abstract Pulmonary sequestration is an infrequent congenital disease characterized by the presence of a portion of pulmonary parenchyma that receives vascularization independent of the systemic circulation. We present three cases of intralobar pulmonary sequestration of late presentation, one of them associated with a cystic adenomatous malformation and in which the management was completed by videothoracoscopy: two of them with total lobectomy and the other with sublobar lobectomy. It is a disease of variable clinical presentation and whose treatment is, in most cases, surgical, usually requiring lobar resections, which can be carried out effectively and safely by video-assisted thoracoscopy.