Although substantial progress was made during the last decade, all replication mechanisms in eucaryotes are not yet understood because: (a) Replication is an event which occurs much more rarely than in bacteria. Initiation of replication is therefore highly controlled; this complicates the understanding of this process; (b) The DNA is not naked, in the cell, but in the form of [...]
The replication of numerous procaryotes was studied in recent years. The mechanisms of the replication of phages T4, T7 and λ are now well known, while those of B. subtilis are beginning to be understood. However, the most extensively studied system remains Escherichia coli, thanks to the combination of various types of approaches. Experimental Approaches to the Study of Replication: [...]
The biosynthesis of the DNA must consist in a replication or duplication. The study of the DNA structure as proposed by Crick and Watson (see fig. 6-15) gives an idea of the mechanism of this replication. Each nucleotide of the template DNA chain need only be recognized by a complementary nucleotide before the latter is incorporated at the end of [...]