Theoretical aspects of translocation on DNA: adenosine triphosphatases and treadmilling binding proteins.

The basic kinetic and bioenergetic theory is outlined for two kinds of translocation on DNA: (i) helicases that use ATP to move along single-stranded DNA or to move on and invade double-stranded DNA at a replication fork; and (ii) DNA-binding proteins (not ATPases) that form bound aggregates on single-stranded DNA and facilitate replication by steady-state treadmilling of molecules between the ends of the aggregate. The respective resemblances to myosin--actin in muscle and to steady-state treadmilling in solution of actin or tubulin are pointed out.