Population Genetic Analysis of Propionibacterium acnes Identifies a Subpopulation and Epidemic Clones Associated with Acne

Abstract

The involvement of Propionibacterium acnes in the pathogenesis of acne is controversial, mainly owing to its dominance as an inhabitant of healthy skin. This study tested the hypothesis that specific evolutionary lineages of the species are associated with acne while others are compatible with health. Phylogenetic reconstruction based on nine housekeeping genes was performed on 210 isolates of P. acnes from well-characterized patients with acne, various opportunistic infections, and from healthy carriers. Although evidence of recombination was observed, the results showed a basically clonal population structure correlated with allelic variation in the virulence genes tly and camp5, with pulsed field gel electrophoresis (PFGE)- and biotype, and with expressed putative virulence factors. An unexpected geographically and temporal widespread dissemination of some clones was demonstrated. The population comprised three major divisions, one of which, including an epidemic clone, was strongly associated with moderate to severe acne while others were associated with health and opportunistic infections. This dichotomy correlated with previously observed differences in in vitro inflammation-inducing properties. Comparison of five genomes representing acne- and health-associated clones revealed multiple both cluster- and strain-specific genes that suggest major differences in ecological preferences and redefines the spectrum of disease-associated virulence factors. The results of the study indicate that particular clones of P. acnes play an etiologic role in acne while others are associated with health.

A novel multilocus sequence typing scheme for the opportunistic pathogen Propionibacterium acnes and characterization of type I cell surface-associated antigens

“…S2, available with the online version of this paper). The MLST clustering of strains into the major genetic divisions was congruent with the results obtained using a combination of antibody typing, single locus typing and RAPD, with a number of notable exceptions ( All isolates within the type II and III clades were negative for sorbitol fermentation and haemolysis, as previously described for these groups (McDowell et al, 2008;Lomholt & Kilian, 2010).…”

“…Compared with other type IA strains, however, SK187 appears more closely related to the type IB division. In addition to sharing the recA GAA 897 SNP with type IB strains, it also contains a genomic region (PPA846-PPA874) as well as other genes (PPA2354-PPA2355; PPA2400) that are present in KPA171202 (type IB 1 ; ST10) (Lomholt & Kilian, 2010). These regions code, for example, for ABC transporters, conjugal transfer systems and lanthionine biosynthesis.…”

“…The absence of type IB strains amongst acne isolates despite their presence on facial skin provides evidence that type IA-specific factors are responsible for the association with acne. While in silico comparisons of CC6 genome sequences (J165, SK137) with those of other type IA strains (SK187), as well as type IB (KPA171202) and II (J139), have found differences with respect to imported island-like regions and genes involved in carbohydrate metabolism, no clear explanation for the dominant role of the ST6 lineage and its descendants in the aetiology of acne can be predicted based solely on gene content (Lomholt & Kilian, 2010). Indeed, despite a small number of inserts and deletions, a high degree of sequence conservation was found throughout the genomes.…”

The diversity and host interactions of Propionibacterium acnes bacteriophages on human skin

“…Our previous 16S ribosomal RNA metagenomic study demonstrated that P. acnes strain population structure in pilosebaceous units differs significantly between acne patients and healthy individuals (Fitz-Gibbon et al, 2013). Certain strains are highly associated with the disease (Lomholt and Kilian, 2010;McDowell et al, 2012;Fitz-Gibbon et al, 2013;Tomida et al, 2013), while some strains are enriched in healthy skin (FitzGibbon et al, 2013).…”

Characterisation of Cutibacterium acnes phylotypes in acne and in vivo exploratory evaluation of Myrtacine®

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AbstractObjective Our main objective was to compare Cutibacterium acnes (C. acnes) skin colonisation in patients with mild to moderate acne versus healthy controls and secondly, to evaluate a Myrtacine â -based cream on C. acnes total population and antibioresistant Cutibacteria in patients with acne.Methods In 60 acne patients (Global Acne Severity Scale, GEA grades 2-3), of mean age 20 [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] Results We first showed (i) high and similar levels of C. acnes colonisation in superficial pilosebaceous follicles and detection of EryR and ClnR strains in both acne and control groups; (ii) different repartition of phylotypes in acne patients versus healthy control, with a predominance of phylotype IA in acne patients and a link between phylotype IA and erythromycin resistance. Besides, after treatment with the Myrtacine â -based cream in acne patients, there was no change in C. acnes total load, but a significant decrease of EryR Cutibacteria, reduced porphyrin production by C. acnes, a decrease in acne severity (GEA), associated with reduced retentional and inflammatory lesions.

Conclusion Cutibacterium acnes colonisation was not significantly different in acne versus control groups.

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