The glycine cleavage system (glycine decarboxylase complex) catalyzes the degradation of glycine. The H protein shuttles the methylamine group of glycine from the P protein to the T protein (By similarity). Binds 1 lipoyl cofactor covalently. Component of the glycine decarboxylase complex (GDC), which is composed of four proteins: P, T, L and H. Belongs to the GcvH family.