Methionine utilization by bifidobacteria: possible existence of a reverse transsulfuration pathway

Although bifidobacteria are already widely used as beneficial microbes with health-promoting effects, their amino acid utilization and metabolism not yet fully understood. Knowledge about the of sulfur-containing acids in is especially limited. In this study, we tested methionine ability several bifidobacterial strains when it was sole available sulfur source. have long been predominantly considered to be cysteine auxotrophs, showed that necessarily case.