In enzymology, a biotin-[methylcrotonoyl-CoA-carboxylase] ligase () is an enzyme that catalyzes the chemical reaction
The 3 substrates of this enzyme are ATP, biotin, and ], whereas its 3 products are AMP, diphosphate, and .
This enzyme belongs to the family of ligases, specifically those forming generic carbon-nitrogen bonds. The systematic name of this enzyme class is biotin:apo-[3-methylcrotonoyl-CoA:carbon-dioxide ligase (ADP-forming)] ligase (AMP-forming). Other names in common use include biotin-[methylcrotonoyl-CoA-carboxylase] synthetase, biotin-beta-methylcrotonyl coenzyme A carboxylase synthetase, beta-methylcrotonyl coenzyme A holocarboxylase synthetase, and holocarboxylase-synthetase. This enzyme participates in biotin metabolism.