EC 4.98 ATP-independent chelatases

ATP-independent chelatases are a special kind of lyases that catalyse the insertion of a metal cation into a an organic molecule, usually a porphyrin ring. The reactions catalysed by the chelatases occur in the opposite direction to the way they are written. Note that chletases that utilize ATP hydrolysis to drive the reaction are classified under subclass EC 6.6.