ATP-dependent RNA helicase required for mitochondrial splicing of group I and II introns. Specifically involved in the ATP-dependent splicing of the bl1 intron of COB. Also required for efficient mitochondrial translation. ATP + H2O = ADP + H(+) + phosphate The Q motif is unique to and characteristic of the DEAD box family of RNA helicases and controls ATP binding and hydrolysis. Present with 10300 molecules/cell in log phase SD medium. Belongs to the DEAD box helicase family. DDX18/HAS1 subfamily.