Research Fellows Directory
Dr Bill Hanage
Imperial College London
My work deals with the genetics of bacteria, which are important players in all of life’s processes, and moreover cause a great deal of human disease. Biologists view species as fundamental units of life, and I use gene sequences to identify species in bacteria, and examine gene flow within and between them.
This gene flow arises because many bacteria are able to take up DNA from other members of the same species, or even different species, and make use of it by inserting it into their own genome. Using DNA sequences from a sample of genes in a large number of bacterial strains I have shown that in the important pathogen Streptococcus pneumoniae, those bacteria which show a history of this are more likely to be resistant to antibiotics.
Why should this be? We have suggested that as a result of mutations, some strains are more likely to take up DNA. If so, they are more likely to pick up a gene for something like antibiotic resistance, which could be useful. They are also more likely to pick up divergent DNA of the sort we detected in general, which explains the association.
We are building on this work to examine other bacterial species, and have found other intriguing patterns suggesting the importance of this process, which is called recombination, in helping bacteria evolve to face the diversity of environments which they inhabit. It is fair to say, that in their adaptation to those environments, and their ability to adapt to them, bacteria are more highly evolved than we are.