Читать книгу Cell Biology - Stephen R. Bolsover - Страница 91

Several copies of the protein DnaA, which is activated by a molecule of ATP, bind to four sequences of nine base pairs within the E. coli origin of replication (ori C). This causes the two strands to begin to separate (or “melt”) because the hydrogen bonds in DNA are broken near to where the DnaA protein binds. The DNA is now in the open complex formation and has been prepared for the next stage in replication, which is to open up the helix even further.