Methylmalonyl-CoA mutase is an enzyme that plays a crucial role in the metabolism of certain fatty acids and amino acids. It catalyzes the conversion of methylmalonyl-CoA to succinyl-CoA, which is an important step in the energy production process within cells. This reaction is vital for the proper breakdown of specific nutrients, allowing the body to utilize them effectively. The enzyme requires adenosylcobalamin, a form of vitamin B12, as a cofactor to function properly. Deficiencies in methylmalonyl-CoA mutase or its cofactor can lead to metabolic disorders, such as methylmalonic acidemia, which can cause various health issues, including developmental delays and neurological problems.