The glycine cleavage system catalyzes the degradation of glycine. (6S)-5,6,7,8-tetrahydrofolate + (R)-N(6)-(S(8)-aminomethyldihydrolipoyl)-L-lysyl-[protein] = (6R)-5,10-methylene-5,6,7,8-tetrahydrofolate + (R)-N(6)-dihydrolipoyl-L-lysyl-[protein] + NH4(+) The glycine cleavage system is composed of four proteins: P, T, L and H. Belongs to the GcvT family.