The smell of supper — and Staphylococcus

I wrote a while ago about mate choice in Drosophila being influenced by differences in the bacteria carried by flies fed on different diets.

Now a new paper (Verhulst et al. 2010. Differential attraction of malaria mosquitoes to volatile blends produced by human skin bacteria.  PLoS ONE doi:10.1371/journal.pone.0015829) suggests that bacteria influence not only mate choice, but also choice of meal.  By mosquitos.  Thanks to the advent of

Panic Caused by a Mosquito in Piccadilly Circus (The Strand Magazine, 1910)

high-throughput rRNA sequencing, it’s now possible to characterize the bacteria found on the skin of individual humans, and it turns out that — funnily enough — we’re all individuals.  So, can we use microbiology to explain the fact that some individuals are visibly more attractive to mosquitoes than others?

It’s previously been shown that if you grow a mix of human skin bacteria on agar, the bacteria produce volatile chemicals that attract mosquitoes.  This paper focuses on cultures of single species of bacteria; mozzies are then offered choices between pairs of cultures to determine their preference for one smell over another. Apparently mosquitoes like the smell of Staphylococcus epidermidis least, of the bacteria tested, and that of Corynebacterium minutissimum most.  The authors trapped the volatile substances produced by the various bacteria on active charcoal and analyzed them, identifying several small organic compounds that are now candidates for mosquito attractants or repellants.  Look out for eau de S. epidermidis this summer as a “natural” alternative to DEET.

Update: I just noticed that Lab Rat posted a while ago on S. epidermidis protecting your throat as well (not from mosquitoes).

Verhulst NO, Andriessen R, Groenhagen U, Bukovinszkiné Kiss G, Schulz S, Takken W, van Loon JJ, Schraa G, & Smallegange RC (2010). Differential attraction of malaria mosquitoes to volatile blends produced by human skin bacteria. PloS One, 5 (12) PMID: 21209854