Acne is not associated with yet-uncultured bacteria

Abstract

Current clinical and microbiological information on acne fails to demonstrate a clear association between particular species, including Propionibacterium acnes, and disease, and the disease continues to be a considerable problem. To test if acne is associated with hitherto uncultured bacteria residing in diseased skin follicles, sequencing and phylogenetic analysis of approximately 5,700 amplified and cloned 16S rRNA genes were used to determine the microbial diversity in follicles from acne patients and healthy individuals and from the superficial skin of acne patients. Follicles from healthy skin were exclusively colonized by P. acnes, whereas the follicular microbiota of acne patients included, in addition, Staphylococcus epidermidis and minor proportions of other species. In comparison, samples from superficial skin showed a complex microbiota represented by 12 to 16 bacterial species. The findings of the study exclude the possibility that acne is associated with yet-uncultured bacteria and shows that healthy skin follicles constitute a remarkably exclusive habitat allowing colonization only by P. acnes.

FIG. 1.

Rarefaction analysis of the combined bacterial 16S rRNA gene library of clones obtained from the superficial skin of two acne-affected individuals. The rarefaction curve, which plots the number of observed OTUs (Mao Tau) as a function of the number of clones, was computed by use of the EstimateS program, together with the corrected Chao1 estimator for species richness.