Development of a highly tolerant bacterial consortium for asphaltene biodegradation in soils.

Asphaltenes are the most polar and heavy fraction of petroleum, and their complex structure and toxicity make them resistant to biodegradation. The ability to tolerate high asphaltene concentrations is crucial to reducing the toxicity-related inhibition of microbial growth and improving their capacity for adaptation, survival, and biodegradation in soils highly contaminated with asphaltenes. This study developed a highly tolerant consortium for efficient asphaltene biodegradation in soils from 22 bacterial isolates obtained from heavy-crude oil-contaminated soils.

Effect of Essential Oil from on the Transcriptional Expression of Genes Related to Quorum Sensing, Biofilm Formation, and Virulence of and .

Microbial infections resistant to conventional antibiotics constitute one of the most important causes of mortality in the world. In some bacterial species, such as and pathogens, biofilm formation can favor their antimicrobial resistance. These biofilm-forming bacteria produce a compact and protective matrix, allowing their adherence and colonization to different surfaces, and contributing to resistance, recurrence, and chronicity of the infections.

Effect of Essential Oils on Growth Inhibition, Biofilm Formation and Membrane Integrity of and .

Biofilm as a cellular conformation confers survival properties to microbial populations and favors microbial resistance. Here, we investigated the antimicrobial, antibiofilm, antimotility, antihemolytic activity, and the interaction with synthetic membranes of 15 essential oils (EOs) on ATCC 25922 and ATCC 29213. Antimicrobial activity of EOs was determined through microdilution method; development of the biofilm was assessed using the crystal violet assay and SEM microscopy.

Genome-Resolved Meta-Analysis of the Microbiome in Oil Reservoirs Worldwide.

Microorganisms inhabiting subsurface petroleum reservoirs are key players in biochemical transformations. The interactions of microbial communities in these environments are highly complex and still poorly understood. This work aimed to assess publicly available metagenomes from oil reservoirs and implement a robust pipeline of genome-resolved metagenomics to decipher metabolic and taxonomic profiles of petroleum reservoirs worldwide.

Construction of PAH-degrading mixed microbial consortia by induced selection in soil.

Bioremediation of polycyclic aromatic hydrocarbons (PAHs)-contaminated soils through the biostimulation and bioaugmentation processes can be a strategy for the clean-up of oil spills and environmental accidents. In this work, an induced microbial selection method using PAH-polluted soils was successfully used to construct two microbial consortia exhibiting high degradation levels of low and high molecular weight PAHs. Six fungal and seven bacterial native strains were used to construct mixed consortia with the ability to tolerate high amounts of phenanthrene (Phe), pyrene (Pyr) and benzo(a)pyrene (BaP) and utilize these compounds as a sole carbon source.

Comparative metagenomic analysis of PAH degradation in soil by a mixed microbial consortium.

In this study, we used a taxonomic and functional metagenomic approach to analyze some of the effects (e.g. displacement, permanence, disappearance) produced between native microbiota and a previously constructed Polycyclic Aromatic Hydrocarbon (PAH)-degrading microbial consortium during the bioremediation process of a soil polluted with PAHs.

Biodegradation of polycyclic aromatic hydrocarbons by Trichoderma species: a mini review.

Fungi belonging to Trichoderma genus are ascomycetes found in soils worldwide. Trichoderma has been studied in relation to diverse biotechnological applications and are known as successful colonizers of their common habitats. Members of this genus have been well described as effective biocontrol organisms through the production of secondary metabolites with potential applications as new antibiotics.

Morphological changes and growth of filamentous fungi in the presence of high concentrations of PAHs.

In this study, we evaluated the effect of low and high molecular weight polycyclic aromatic hydrocarbons (PAHs), i.e., Phenanthrene, Pyrene and Benzo[a]pyrene, on the radial growth and morphology of the PAH-degrading fungal strains Aspergillus nomius H7 and Trichoderma asperellum H15.

Degradation of polycyclic aromatic hydrocarbons in soil by a tolerant strain of Trichoderma asperellum.

Trichoderma asperellum H15, a previously isolated strain characterized by its high tolerance to low (LMW) and high molecular weight (HMW) PAHs, was tested for its ability to degrade 3-5 ring PAHs (phenanthrene, pyrene, and benzo[a]pyrene) in soil microcosms along with a biostimulation treatment with sugarcane bagasse. T. asperellum H15 rapidly adapted to PAH-contaminated soils, producing more CO2 than uncontaminated microcosms and achieving up to 78 % of phenanthrene degradation in soils contaminated with 1,000 mg Kg(-1) after 14 days.

Direct analysis of genetic variability in Trypanosoma cruzi populations from tissues of Colombian chagasic patients.

The clinical symptoms of Chagas disease are highly variable and are correlated with geographical distribution and parasite genetic group. Trypanosoma cruzi group I is associated with chagasic cardiomyopathy in Colombia and other countries in northern South America. However, in southern South America, T cruzi group II predominates and is associated with cardiomyopathy and digestive forms of the disease.

Mixed infection of Trypanosoma cruzi I and II in a Colombian cardiomyopathic patient.

The Trypanosoma cruzi taxon is composed of 2 major lineages, T cruzi I and T cruzi II. The clinical symptoms of Chagas disease are highly variable, and their geographic distribution is correlated with the distribution of the parasite lineages. In Colombia and northern South America, T cruzi I lineage is associated with chagasic cardiomyopathy.

Evidence of Trypanosoma cruzi II infection in Colombian chagasic patients.

Trypanosoma cruzi is genetically classified into at least two major lineages named T. cruzi I (also named Tc I) and T. cruzi II (also named Tc IIb).

Polymorphisms of toll-like receptor 2 and 4 genes in Chagas disease.

The aim of this study was to test the possible implication of toll-like receptor 2 (TLR2) and TLR4 gene polymorphisms in determining the susceptibility to Chagas' disease. Genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism in 475 individuals from Colombia, 143 seropositive with chagasic cardiomyopathy, 132 seropositive asymptomatic and 200 seronegative. The TLR2 arginine to glutamine substitution at residue 753(Arg753Gln) polymorphism was absent in the groups analyzed.

[Seroprevalence of Chagas disease and associated risk factors in a population of Morroa, Sucre].

Introduction: Chagas disease is a major public health problem in Latin America. In Colombia, a large area has the ecoepidemiological conditions which favor the active transmition of this infection.

Objective: This study was undertaken in a population from the municipality of Morroa, Sucre Province, to evaluate risk factors and to determine the seroprevalence to Chagas disease.

Polymorphism in the 3' UTR of the IL12B gene is associated with Chagas' disease cardiomyopathy.

The aim of this study was to investigate the possible influence of a 3' untranslated region (3' UTR) polymorphism of the IL12B gene in susceptibility to Trypanosoma cruzi infection or in the development to cardiomyopathy in Chagas' disease (CD). We determined the IL12B 3' UTR genotypes in a sample of 200 seronegative individuals and 260 serologically positive patients (130 with Chagasic cardiomyopathy and 130 asymptomatic). All individuals are from a Colombian region where T.

Interleukin-1 gene cluster polymorphism in chagas disease in a Colombian case-control study.

The aim of this study was to assess the possible association between the IL1A, IL1B and IL1RN gene polymorphisms and Chagas disease. Our study population consisted of 130 serologically positive cardiomyopathic patients and 130 seropositive and asymptomatic individuals from a Colombian population where Trypanosoma cruzi infection is endemic. Genotyping of the IL1A (-889C/T, +4845G/T), IL1B (-511C/T, -31T/C, +3954T/C, +5810G/A) and IL1RN (+8006T/C, +8061C/T, +11100T/C) polymorphisms was performed by polymerase chain reaction-restriction fragment length polymorphism and polymerase chain reaction sequence-specific primer methods.