Functional implications of residues of the B′ motif of geminivirus replication initiator protein in its helicase activity

Geminivirus replication initiator protein (Rep) is a multifunctional viral required for replication. During the process of replication, Rep acts as site- and strand-specific endonuclease, ligase, ATPase, helicase. B' motif β-hairpin loop geminivirus are conserved important Rep-mediated helicase activity To dissect roles various amino acid residues in its unwinding DNA, we investigated eight near ATP active site or ssDNA contact channel. Our strategy was to mutate these alanines investigate effects mutations on biochemical activities associated with DNA unwinding. We looked into binding, hydrolysis, wild-type mutant proteins. These investigations showed four (Arg279, Asp280, Tyr287, Pro290) affecting activity. A structural model analysis confirmed binding be connected through structure, suggesting that changes one might affect other function by acting concert. Viral genomes containing proteins having did not replicate planta. Taken together, results indicated all implicated mediated demonstrated significance, C-terminal region protein.