(*) 5'-3' kinds require a covalent bond to single strands, and all of them move along a phosphodiester backbone of a nucleic acid.
One of these is a homohexamer structured to have a hole in its center, and it hydrolyzes ATP which shifts the structure of what it binds to. That specific kind is diametric and is structured in 6 bundles. They can activate primase, and they come in rho and DNAb families, along with superfamilies based on motifs found in their structures. (*) 5'-3' kinds require a covalent bond to single strands, and all of them move along a phosphodiester backbone of a nucleic acid. FTP name this class of enzymes that separate nucleic acid strands before replication and are named for DNAs structure. 
One of these is a homohexamer structured to have a hole in its center, and it hydrolyzes ATP which shifts the structure of what it binds to.
Helicase 