The invention is concerned with a novel human intestinal isolate capable of converting L- lysine into butyrate and/or of converting fructose-lysine into butyrate. The novel isolate can be used as a probiotic or supplement to promote production of butyrate in the Gl tract, thereby preventing and/or treating conditions or diseases that benefit from the production of butyrate. Additionally, the isolate may prevent and/or treat conditions or diseases caused by an excess of pathogenic bacteria in the Gl tract, mediated by L-lysine, or mediated by fructose-lysine or other advanced glycation end products.