HEALTHY skin has a specialised chemical defence mechanism that selectively targets the common gut bacterium Escherichia coli.
E. coli cannot survive for long on healthy skin but can infect burnt or damaged skin. So Jens-Michael Schröder of the University Hospital Schleswig-Holstein in Kiel, Germany, was keen to find out what was killing the bacteria. “Infection of skin is a rare event,” says Schröder, “we want to know why.”
Schröder’s team tested skin proteins until they found one called psoriasin that killed E. coli but left other skin bacteria unharmed. To prove the protein was responsible, the team blocked psoriasin’s action by adding antibodies that…
