The invention relates to the field of probiotic and in particular to bacteria of the species Bacteroides faecichinchilleae and its use for treating metabolic disorders. Performing an original screening test, the present inventors identified a novel species of commensal bacteria, Bacteroides faecichinchilleae, which possesses the ability to improve glucose tolerance in a preclinical model of diabetes, with a unique mechanism of action, closely related to the mechanism of anti-diabetic drug metformin such as inhibition of FXR activity in the small intestine (through modifications of intestinal bile acid profile) and reduction of ceramide levels in the liver (especially C16-ceramides). Thus this study opens the way to safe use of Bacteroides faecichinchilleae and accordingly the present invention provides an Bacteroides faecichinchilleae and its use as a drug or probiotic and more particularly for use in the treatment of metabolic disorders such as type 2 diabetes, alone or in combination with classical antidiabetic drug metformin.