‘BO enzyme’ discovery suggests smell emerged before modern humans

Researchers have discovered the enzyme responsible for body odour, which could help lead to new treatments.

Researchers from the University of York have sniffed out the key enzyme responsible for body odour (BO), which may have played an important role for our distant ancestors. Writing in Scientific Reports, the researchers in collaboration with Unilever described how particular bacteria have evolved a special enzyme to produce some of the key molecules we recognise as BO.

“Solving the structure of this BO enzyme has allowed us to pinpoint the molecular step inside certain bacteria that makes the odour molecules,” said Dr Michelle Rudden of the University of York, who co-authored the study.

“This is a key advancement in understanding how body odour works, and will enable the development of targeted inhibitors that stop BO production at source without disrupting the armpit microbiome.”

The findings showed how Staphylococcus hominis is one of the main microbes behind body odour, as part of the diverse community of bacteria found naturally in the skin. The researchers also discovered that the BO enzyme was present in S hominis long before the emergence of Homo sapiens as a species.

Communication through smell

This suggests that body odour existed prior to the evolution of modern humans and may have been crucial in how our ancestral primates communicated in social groups.

Dr Gordon James of Unilever, who also co-authored the study, said this research “was a real eye-opener”.

“It was fascinating to discover that a key odour-forming enzyme exists in only a select few armpit bacteria – and evolved there tens of millions of years ago,” he said.

Researchers from the University of York – including some of those involved in this latest study – previously published research that revealed how the Staphylococcus bacteria actually transform odourless compounds into smells.

The ‘transport protein’ – as it is referred to – enables bacteria to recognise and swallow up the odourless compounds, and transform them into sweat.