Molecular function

5-pyrophosphomevalonate decarboxylase activity, ATP:(R)-5-diphosphomevalonate carboxy-lyase (adding ATP; isopentenyl-diphosphate-forming), ATP:(R)-5-diphosphomevalonate carboxy-lyase (dehydrating), mevalonate 5-diphosphate decarboxylase activity, mevalonate diphosphate decarboxylase activity, mevalonate pyrophosphate decarboxylase activity, mevalonate-5-pyrophosphate decarboxylase activity, pyrophosphomevalonate decarboxylase activity, pyrophosphomevalonic acid decarboxylase activity

Catalysis of the reaction: (R)-5-diphosphomevalonate + ATP = ADP + CO2 + H+ + isopentenyl diphosphate + phosphate.