Project description:Our goal is to convert methane efficiently into liquid fuels that may be more readily transported. Since aerobic oxidation of methane is less efficient, we focused on anaerobic processes to capture methane, which are accomplished by anaerobic methanotrophic archaea (ANME) in consortia. However, no pure culture capable of oxidizing and growing on methane anaerobically has been isolated. In this study, Methanosarcina acetivorans, an archaeal methanogen, was metabolically engineered to take up methane, rather than to generate it. To capture methane, we cloned the DNA coding for the enzyme methyl-coenzyme M reductase (Mcr) from an unculturable archaeal organism from a Black Sea mat into M. acetivorans to effectively run methanogenesis in reverse. The engineered strain produces primarily acetate, and our results demonstrate that pure cultures can grow anaerobically on methane.
Project description:Agilent 4x44k Whole Mouse Genome v1 Microarrays were used to analyze aortic transcriptome of mice substituted with medroxyprogesterone acetate, norethisterone acetate or placebo after having been ovariectomized. The aim of this experiment was to detect genes regulated in the gestagen-treated groups as compared to placebo that might be involved in thrombotic events Aortic gene expression was analyzed in ApoE-deficient mice after ovariectomy and 90 days of hormone- or placebo-treatment (medroxyprogesterone acetate or norethisterone acetate) and feeding a high-fat Western-type diet.
Project description:The objetive of this study was to evaluate the impact of acetate pre-treatment in alveolar macrophage like cells (MPI) stimulated with Streptococcus pneumoniae. We observed that acetate induce a high modulation of gene expression. Acetate led to similar numbers of up and down-regulated genes and in a enrichment analysis, acetate was shown to regulate different pathways, such as locomotion, cell proliferation and immune processes.
Project description:Little is known about the bacteria that reside in human gallbladder and the mechanisms that allow them to survive within this harsh environmental niche. Furthermore, certain bacterial species are considered to exhibit antagonistic activities whilst others may form mutualistic interactions through, for example, cross-feeding. We isolated two new strains from healthy human bile samples, one belonging to Ruminococcus gauvreauii, of Lachnospiraceae family, and other constituting a new specie in Ruminococcaceae family, named Ruminocoides biliarensis. The two strains differed markedly in their carbohydrate metabolism as R. gauvreauii mainly metabolised sugar alcohols, including inositol, to form acetate as unique fermentation product, and Rc. biliarensis mainly metabolised resistant starches to mainly form formate and acetate as fermentation end products. Both strains exhibited resistance to different bile salts, and the ability to sporulate. Amino acid and vitamin biosynthesis profiles also markedly differed between the two bile isolates. Finally,RNAseq was used to analyse the co-cultures of both isolates, to analyze the activities involved in the possible cross-feeding relationship.
Project description:Constricting pythons, known for their ability to consume infrequent, massive meals, exhibit rapid and reversible cardiac hypertrophy following feeding. Our primary goal was to investigate how python hearts achieve this adaptive response after feeding. Isolated myofibrils increased force after feeding without changes in sarcomere ultrastructure and without increasing energy cost. Ca2+ transients were prolonged after feeding with no changes in myofibril Ca2+ sensitivity. Feeding reduced titin-based tension, resulting in decreased cardiac tissue stiffness. Feeding also reduced the activity of sirtuins, a metabolically-linked class of histone deacetylases, and increased chromatin accessibility. A transcription factor enrichment analysis on transposase-accessible chromatin with sequencing (ATAC-Seq) revealed the prominent role of transcription factors YY1 and NRF1 in post-feeding cardiac adaptation. Gene expression was also changed in favor of translation and metabolism. Finally, metabolomics analysis and ATP production assay demonstrated that cardiac adaptation after feeding not only increased energy demand but also energy production. These findings have broader implications for our understanding of cardiac adaptation across species and hold promise for the development of innovative approaches to address cardiovascular diseases.