That accomplishment, the researchers said, sets the stage for studies that can uncover what happens when DNA copying mistakes are made that can lead to cancer and other diseases.
The Ohio State University scientists said they are the first to observe real-time behavior of all four sections, or domains, of an enzyme called Dpo4.
The research defines critical steps in the process that starts when the enzyme binds to the correct nucleotide and ends when that nucleotide is put in place to become part of the string of molecules that compose a copied strand of DNA, the scientists said.
"Gaining insight into complex DNA transactions is fundamental to understanding the molecular basis of disease," said Associate Professor Zucai Suo, the study's senior author.
The research that included Cuiling Xu, Brian Maxwell and Likui Zhang is detailed in the early online edition of the journal PLoS Biology.