Area Editoriale
Theworldwide obesity epidemic is stimulating efforts to identify host andenvironmental factors that affect energy balance. Comparisons of the distal gutmicrobiota of genetically obese mice and their lean littermates, as well asthose of obese and lean human volunteers have revealed that obesity isassociated with changes in the relative abundance of the two dominant bacterialdivisions, the Bacteroidetes and the Firmicutes. Here we demonstrate throughmetagenomic and biochemical analyses that these changes affect the metabolicpotential of the mouse gut microbiota. Our results indicate that the obesemicrobiome has an increased capacity to harvest energy from the diet.Furthermore, this trait is transmissible: colonization of germ-free mice withan 'obese microbiota' results in a significantly greater increase in total bodyfat than colonization with a 'lean microbiota'. These results identify the gutmicrobiota as an additional contributing factor to the pathophysiology ofobesity. Leggil'articolo