The glycine cleavage system catalyzes the degradation of glycine. The P protein binds the alpha-amino group of glycine through its pyridoxal phosphate cofactor; CO(2) is released and the remaining methylamine moiety is then transferred to the lipoamide cofactor of the H protein.
Involvement in disease
Defects in GLDC are a cause of non-ketotic hyperglycinemia (NKH) [MIM:605899]; also known as glycine encephalopathy (GCE). NKH is an autosomal recessive disease characterized by accumulation of a large amount of glycine in body fluid and by severe neurological symptoms.