Bacteria smells

Bacteria not only produce foul smells, but can also detect chemicals releases by potential competitors before producing a slime to ward them off.

A team of marine biologists at Newcastle University’s Dove Marine Laboratory found that bacteria have a molecular nose that can detect airborne smell-producing chemicals such as ammonia, which may be produced by rival bacteria.

The bacteria responds by producing slime – a biofilm, where individual bacteria join together to colonise an area to push out their competitor.

“This is the first evidence of a bacterial ‘nose’ capable of detecting potential competitors,” said Dr Reindert Nijland, research leader, “Slime is important in medical and industrial settings and the fact that the cells formed slime on exposure to ammonia has important implications for understanding how biofilms are formed and how we might be able to use this to our advantage.”

Nijland’s team showed two rival bacteria – Bacillus subtilis and Bacullus licheniformus – formed biofilms in response to airborne ammonia and that the response decreased the further apart the two colonies were placed.

“The sense of smell has been observed in many creatures, even yeasts and slime moulds, but our work shows for the first time that a sense of smell even exists in lowly bacteria,” said project supervisor Professor Grant Burgess, “From an evolutionary perspective, we believe this may be the first example of how living creatures first learned to smell other living creatures.”

Biofilms can be a major source of infection on medical implants like heart valves, artificial hips and breast implants. It also costs the marine industry millions each year as biofilms slow ships down and waste fuel. However, certain biofilms can be used to clear up oil spills.