The gut bacterium Escherichia coli has, for a variety of reasons, become a model organism for studying many of life's essential processes. Due to its rapid growth rate, simple nutritional requirements, well established genetics and completed genomes sequence, more is now known about E. coli than any other living organism.
The preferred source of nitrogen for E. coli, as for many bacteria, is ammonium from which the primary nitrogen donor molecules glutamate and glutamine are synthesised. The movement of ammonium into the cell across the cytoplasmic membrane is consequently a key process in nitrogen metabolism and this is achieved by the ammonium transport (Amt) proteins. Amt proteins are found in virtually all living organisms and in the lab of Dr. Mike Merrick the E. coli AmtB protein has been developed as a model system to gain insight into this fundamental biological process.
E.coli is the model organism of choice for investigations of many fundamental biological processes and another such example is in the study of DNA topoisomerases. These are a vitally important class of proteins involved in the control of the topological state of DNA and their major biological functions are in DNA replication, recombination and the control of gene expression. One of the best characterised DNA topoisomerases is DNA gyrase from E. coli which is studied by Prof. Tony Maxwell. E. coli is also being used to investigate genome stability by Dr. Richard Bowater. The role of long triplet repeats in DNA stability is being investigated along with the biochemical mechanisms which generate these instabilities.
