BCH311H1 Lecture Notes - Lecture 5: Dna Replication, Thymidine Triphosphate, Exonuclease

• School: UTSG
• Department: Biochemistry
• Course: BCH311H1
• Professor: Stavroula Andreopoulos

Document Summary

Now our model for deoxyribonucleic acid is, in effect, a pair of templates, each of which is complementary to the other. We imagine that prior to duplication the hydrogen bonds are broken, and the two chains unwind and separate. Each chain then acts as a template for the formation on to itself of a new companion chain, where we only had one before. Moreover, the sequence of the pairs of bases will have been duplicated exactly. Properties of dna replication: 5" to 3"; requires a primer; semi-conservative; bi-directional; semi-discontinuous. Hypothesized that existing chains were being elongated by the enzyme: The other three dntps had to be present for dttp to be incorporated. The newly synthesized dna had the same at to gc ratio as the primer dna. The composition of the product did not depend on the concentration of individual dntps in the rxn.