Long suspected as a cause of acne, the pore-dwelling bacterial species Propionibacterium acnes may not uniformly deserve its bad name. While some strains of the bacterium are associated with pimples, investigators have found another strain is associated with clear skin, according to a study published yesterday (February 28) in the Journal of Investigative Dermatology.
“Just like good strains of bacteria in yogurt, for example, are good for the gut, these good strains of P. acnes could be good for the skin,” Huiying Li, one of the paper’s authors and a molecular biologist at University of California, Los Angeles, told ScienceNOW.
Li and coauthors used pore-cleansing strips to collect samples at clinics in California from 101 peoples’ noses, half with acne and half with clear skin. They confirmed that P. acnes was the dominant species in the pores and found that overall levels of the bacteria did not vary significantly based on whether subjects had acne or not. However, people without acne tended to harbor the strain RT6, while the acne-ridden were strongly associated with the strains RT4 and RT5.