July 27 (UPI) -- What makes body odor so smelly? According to scientists, the main culprit is a newly discovered enzyme, creatively called the "body odor enzyme."
Previous studies have shown that only a handful of bacteria are responsible for the odors emanating from sweaty armpits.
A study published Monday in the journal Scientific Reports suggests these bacteria have evolved a specialized enzyme that produces the molecules responsible for body odor's recognizable stench.
"Solving the structure of this 'BO enzyme' has allowed us to pinpoint the molecular step inside certain bacteria that makes the odor molecules," study co-author Michelle Rudden said in a news release.
"This is a key advancement in understanding how body odor works, and will enable the development of targeted inhibitors that stop BO production at source without disrupting the armpit microbiome," said Rudden, a biologist and research associate at the University of York in Britain.
According to the new analysis, one of the main bacterial strains responsible for the production of newly discovered BO-generating enzyme is Staphylococcus hominis.
Staphylococcus hominis and its close relatives evolved alongside early humans for thousands, perhaps millions, of years. The bacteria group predates modern humans, Homo sapiens.
"This group of malodor producing staphylococci must have been present in ancestral human populations potentially dating back to primates," researchers wrote in their paper.
The ancient origins of odor-producing staphylococci suggests the bacteria may have played an important role in communications among primates and early humans.
"This research was a real eye-opener," said study co-author Gordon James, a researcher with the British consumer goods company Unilever. "It was fascinating to discover that a key odor-forming enzyme exists in only a select few armpit bacteria -- and evolved there tens of millions of years ago."
Scientists suggest more research is needed to better understand the evolutionary relationship between human armpits and staphylococci bacteria.