Which proteins are found in most prokaryotes and eukaryotes?

DEAD-box proteins are found in most prokaryotes and eukaryotes, but not all. They are involved in an assortment of metabolic processes that typically involve RNAs. Also, in some cases, they are involved with other nucleic acids. They are highly conserved in nine motifs.

DEAD-box proteins catalyze the ATP-dependent unwinding of RNA duplexes. The common unit of these enzymes is a helicase core of two flexibly linked RecA domains. ATP binding and phosphate release control opening and closing of the cleft in the helicase core. This movement coordinates RNA-binding and ATPase activity and is thus central to the function of DEAD-box helicases. In most DEAD-box proteins, the helicase core is flanked by ancillary N-and C-terminal domains. The DEAD-box proteins are vitally important to cellular processes; they make up the largest class of helicases.