Methanogens, Methane and Gastrointestinal Motility

Anaerobic fermentation of the undigested polysaccharide fraction of carbohydrates produces hydrogen in the intestine which is the substrate for methane production by intestinal methanogens. Hydrogen and methane are excreted in the flatus and in breath giving the opportunity to indirectly measure their production using breath testing. Although methane is detected in 30%-50% of the healthy adult population worldwide, its production has been epidemiologically and clinically associated with constipation related diseases, like constipation predominant irritable bowel syndrome and chronic constipation. While a causative relation is not proven yet, there is strong evidence from animal studies that methane delays intestinal transit, possibly acting as a neuromuscular transmitter. This evidence is further supported by the universal finding that methane production (measured by breath test) is associated with delayed transit time in clinical studies. There is also preliminary evidence that antibiotic reduction of methanogens (as evidenced by reduced methane production) predicts the clinical response in terms of symptomatic improvement in patients with constipation predominant irritable bowel syndrome. However, we have not identified yet the mechanism of action of methane on intestinal motility, and since methane production does not account for all constipation associated cases, there is need for high quality clinical trials to examine methane as a biomarker for the diagnosis or as a biomarker that predicts antibiotic treatment response in patients with constipation related disorders.

Aislamiento e identificación de microorganismos del género Methanococcus y Methanobacterium de cuatro fuentes de Bogotá, DC / Isolation and identification of methanococcus and methanobacterium microorganisms from four different sources in Bogota, DC

Las bacterias metanogénicas obtienen su energía mediante la producción metabólica de gas metano, utilizando sustratos como dióxido de carbono, acetato y sustratos de metilo a través de procesos de hidrólisis y acetogenesis y son esenciales en la degradación anaerobia de la materia orgánica en la naturaleza. El propósito de esta investigación fue aislar bacterias metanogénicas para conservarlas en la colección de cultivos de la Universidad Colegio Mayor de Cundinamarca. El muestreo se realizó por duplicado de cuatro fuentes ubicadas en Bogotá D.C, Colombia, las cuales ofrecían las características ambientales para su desarrollo. El procedimiento incluyó la toma de la muestra en ambiente anaerobio, aislamiento en medios selectivos e identificación por observación de las características microscópicas con coloración de Gram y de características macroscópicas en los medios selectivos y verificación de producción de metano mediante prueba piloto. Los resultados permitieron evidenciar la presencia de bacterias de los géneros Methanococcus y Methanobacterium a partir de las fuentes seleccionadas para el estudio. Se concluyó que el mejor método para la conservación de estos géneros es la congelación con la adición de agentes reductores y glicerol como criopreservante.

Comparative genomics using data mining tools.

We have analysed the genomes of representatives of three kingdoms of life, namely, archaea, eubacteria and eukaryota using data mining tools based on compositional analyses of the protein sequences. The representatives chosen in this analysis were Methanococcus jannaschii, Haemophilus influenzae and Saccharomyces cerevisiae. We have identified the common and different features between the three genomes in the protein evolution patterns. M. jannaschii has been seen to have a greater number of proteins with more charged amino acids whereas S. cerevisiae has been observed to have a greater number of hydrophilic proteins. Despite the differences in intrinsic compositional characteristics between the proteins from the different genomes we have also identified certain common characteristics. We have carried out exploratory Principal Component Analysis of the multivariate data on the proteins of each organism in an effort to classify the proteins into clusters. Interestingly, we found that most of the proteins in each organism cluster closely together, but there are a few 'outliers'. We focus on the outliers for the functional investigations, which may aid in revealing any unique features of the biology of the respective organisms