The amazing world of bacteria: why it matters!

Professor Stephen Busby, University of Birmingham

Bacteria generally receive a ‘bad press’, and most folk only think about them when they or a family
member suffers from an infection. Surveys find that people are unaware that the vast majority of
bacteria are completely harmless, and that many are positively beneficial to human life. The best
explanation for this apathy is that the general public doesn’t grasp that bacteria were present on
earth long before humans, and that humans evolved in a ‘sea’ of bacteria. Hence, in the first part of
my presentation, I will give a very brief overview of how life on earth is thought to have evolved,
and the essential role of microbes in general, and bacteria in particular. Bioscientists are
fascinated by how molecules act together to generate life, and I will explain how bacteria make
great case studies, and argue that humans today may well need help from bacteria to resolve
current intractable problems.

In the second part of the presentation, I will focus on the small number of bacteria that are
harmful to human health and explain why they evolved. Over the past century, antibiotics have
given humans the ‘upper hand’ in their struggle against these bacteria, but we now know that the
bacteria are fighting back with the spread of genes that encode resistance. I will explain why this
is to be expected in the context of evolution, and tell you about some alternatives for fighting
bacterial infections that don’t rely on the use of antibiotics.