Function
Cystathionine β-lyase (CBL) belongs to a family of PLP-dependent enzymes which cleave C β-S bonds in a variety of subtsrates. PLP is a pyridoxal phosphate. CBL catalyzes a reaction specific for methionine biosynthesis[1]. CBL converts L-cystathionine to L-homocysteine, pyruvate and ammonia. Cystathionine γ-lyase (CGL) is PLP-dependent and breaks cystathionine to cysteine, ketobutyrate and ammonia[2].
Disease
CGL deficiency mediates neurodegeneration in Huntington's disease[3].
Structural highlights
The structure of the EcCBL shows 3 spatially different domains. The (residues 1-60) contributes to the . The (residues 61-256) binds to the PLP and the (residues 257-395). and mediates the proton transfer between Cα and Sγ[4]. . Water molecules are shown as red spheres.
