Читать книгу Cell Biology - Stephen R. Bolsover - Страница 90

The DNA molecule must be opened up before replication can proceed. The helix is a very stable structure, and in a test tube the two strands separate only when the temperature reaches about 90 °C. In the cell, the combined actions of several proteins help to separate the two strands. Much of our knowledge of replication comes from studying E. coli, but similar systems operate in all organisms, bacteria, archaea, and eukaryotes. The proteins E. coli uses to open up the double helix during replication include DnaA, DnaB, DnaC, and single‐stranded DNA‐binding proteins.

Figure 4.1. DNA replication. The helicases, and the replication fork, are moving to the left.