Bacterial research hits the big time
A combination of powerful new analysis methods and abundant data from genomics projects is carrying microbiology forward into a new era.
Bacteria in particular are shedding light on fundamental molecular and signalling processes of interest not just within microbiology, but across the whole spectrum of life sciences embracing higher organisms, including plants and vertebrates. Medical research will benefit through improved knowledge of how bacteria behave when inside host organisms such as humans, both in benevolent symbiotic relationships and when causing infectious diseases such as TB.
But the greatest immediate interest in the field lies in the huge potential created by new methods for probing fundamental mechanisms of biology, according to Mark Buttner, who chaired a recent conference organised by the European Science Foundation (ESF) designed to bring together specialists from different fields relevant to bacterial research.
'A feeling emerged from the conference that there has never been a better time to be a microbiologist,' said Buttner, who is a project leader at the John Innes Centre, an independent laboratory dedicated to plant and micro-organism research in Norwich, UK. 'Rapid progress is coming about as a result of the shear amount of biological information made available by genomics and by the new and very powerful methods that are now available to analyse and predict microbial growth and behaviour systematically and quantitatively.'
Already the new methods have led to a number of exciting and unexpected discoveries, some of which were revealed at the ESF conference. These related mostly to signalling processes, both at the molecular level within individual bacteria cells, and also between cells within colonies or biofilms. Some of these processes had been thought to operate only within higher organisms, in particular multi-cellular animals and plants.
For example small intracellular (within cell) signalling molecules called second messengers play a much bigger role in bacteria than had been thought. These molecules are called second messengers because they generate signals inside a cell in response to a primary external signal coming from the outside environment, such as an attack by a host immune system. As Buttner noted, second messengers were known to play an important role in complex eukaryotes, for example in controlling processes as important as vision and smell in animals. But the full role of such molecules in controlling bacterial physiology is only just being appreciated.
Even though bacteria are single celled organisms, they engage in complex relationships within communities, for example in biofilms where the cells generate a collective protective coating called the extracellular matrix. Second messengers are now being found to play a major role not just within free-living cells, but also in maintaining these communities, particularly in the face of environmental insults, such as action of a host immune system, or indeed of an antibiotic drug. Knowledge of how second messengers operate could therefore help combat bacterial infections involving biofilms, such as orthodontal disease and TB.