Replication of adenovirus DNA in vitro is ATP‐independent

Abstract
Using a reconstituted system for adenovirus DNA replication we tested the requirements for ATP and divalent cations. At the standard Mg2+ concentration ATP stimulated initiation 5 to 10‐fold. However, this effect was caused by complexing Mg2+. At the optimal Mg2+ concentration ATP was not required for initiation or elongation. Besides Mg2+ also Mn2+, Ca2+ and Ba2+ were shown to support initiation whereas for elongation only Mg2+ was accepted. Since Mn2+could efficiently be used for DNA chain elongation on synthetic templates we hypothesize that Mg2+ is essential for the transition of initiation to elongation.