Hydrolyzes 3-hydroxyisobutyryl-CoA (HIBYL-CoA), a saline catabolite. Has high activity toward isobutyryl-CoA. Could be an isobutyryl-CoA dehydrogenase that functions in valine catabolism. Also hydrolyzes 3-hydroxypropanoyl-CoA.
Highly expressed in liver and kidney, also detected in heart, muscle and brain (at protein level). Not detected in lung.
Amino-acid degradation; L-valine degradation.
Involvement in disease
Defects in HIBCH are the cause of HIBCH deficiency (HIBCHD) [MIM:250620]; also known as deficiency of beta-hydroxyisobutyryl CoA deacylase or methacrylic aciduria. The enzyme defect results in accumulation of methacrylyl-CoA, a highly reactive compound, which readily undergoes addition reactions with free sulfhydryl groups. Affected individuals showed delayed development of motor skills, hypotonia, initial poor feeding, and a deterioration in neurological function during first stages of life.
Belongs to the enoyl-CoA hydratase/isomerase family.