Scientists have found that some bacteria and viruses use a novel approach to manufacture the DNA base thymidylate. They follow a chemical pathway utilising the enzyme, flavin-dependent thymidylate synthase (FDTS). Thymidylate is also used as a DNA base in humans, however it is made through a pathway using the enzyme, thymidylate synthase (TS) instead. Both pathways result in the addition of a methyl group to the precursor molecule, but accomplish this in structurally different ways. The first step in the FDTS pathway is to transfer a hydride (a proton plus two electrons) to a deoxy-uridine monophosphate (dUMP), whereas the TS pathway starts with bonding an amino acid to a dUMP.The discovery of both the structurally different chemical reactions taking place in these pathways and the use of different enzymes could lead to advances in developing antibiotics and antiviral drugs. These would target the bacteria and virus pathways, without effecting human DNA synthesis. They could also inhibit the activity of FDTS enzymes with low toxicity for patients.
Created by Anita Cosgrove (41868472).
References:
'New chemical reaction for DNA production in bacteria and viruses discovered', Science Daily, viewed 19 April 2009, <http://www.sciencedaily.com/releases/2009/04/090416161133.htm>.
'Scientists discover new chemical reaction for DNA production in bacteria and viruses', National Science Foundation, viewed 19 April 2009, <http://www.nsf.gov/news/news_summ.jsp?cntn_id=114598>.
