5. Making DNA

About this Lecture

Lecture

In the fifth mini-lecture, we return to synthesising DNA and focus on the step-by-step process of adding new nucleotides to a growing strand of DNA. In this, we understand how new phosphodiester bonds are formed, how the correct base is added to the growing strand each time, and the direction that DNA is always synthesised. However, if we know that DNA is made only in one direction, how are the two strands synthesised if they run antiparallel? This lecture explains how this is possible, with help from modern experimental work that has uncovered new structures and proteins that make this possible.

Course

In this lecture, Professor Richard Bowater (University of East Anglia) talks about DNA, its structure, its replication and how it can code for proteins. To do so, we: (i) discuss the microscopic structure of DNA, looking at what each monomer (nucleotide) is made of; before (ii) understanding the history of its discovery and the macroscopic structure; following onto (iii) DNA polymerase and its role in DNA synthesis; which then goes on to (iv) the coding and non-coding sections of DNA and how four nucleotides code for 20 amino acids; before (v) diving into the step-by-step process of how new nucleotides are added to DNA; and then finally (vi) understanding how DNA can be mutated and damaged, and some of the implications this can have on the proteins it codes for.

Lecturer

Having trained as a biochemist, Professor Richard Bowater's research interests broadened out to encompass methodologies that involve biophysical chemistry, microbiology, molecular biology and bioinformatics. His research focuses on macromolecular interactions of bacterial DNA repair proteins, particularly DNA and RNA ligases, with experiments performed in vitro or in bacterial model organisms. His areas of expertise include the relationship of genetic instabilities to human diseases; trinucleotide (triplet) repeat expansions and human neurodegenerative disorders; DNA repair processes; and protein-protein and protein-DNA interactions.