cystathionine beta-synthase

(redirected from beta-thionase)

cys·ta·thi·o·nine β-syn·thase

(sis'tă-thī'ō-nēn sin'thās),
An enzyme catalyzing the reversible hydrolysis of l-cystathionine to l-serine and l-homocysteine. A step in cysteine biosynthesis and in methionine catabolism. A deficiency of this enzyme leads to vascular thrombosis, dislocation of ocular lens, and abnormal development.
See also: cystathionine γ-synthase.

cystathionine β-synthase

/cys·ta·thi·o·nine β-syn·thase/ (sin´thās) a pyridoxal phosphate–containing lyase that catalyzes a step in the catabolism of methionine; deficiency occurs in an aminoacidopathy characterized by homocystinuria, elevated blood methionine levels, and abnormalities in the eye and the skeletal, nervous, and vascular systems.