Partial atlE sequencing of Staphylococcus epidermidis strains from prosthetic joint infections

Abstract

Partial atlE sequencing (atlE nucleotides 2782 to 3114 [atlE(2782-3114)]) was performed in 41 Staphylococcus epidermidis isolates from prosthetic joint infections (PJIs) and 44 isolates from skin as controls. The atlE(2782-3114) allele 1 (type strain sequence) was significantly more frequent in PJI strains (38/41 versus 29/44 in controls; P = 0.0023). Most PJI strains were positive for mecA, icaA/icaD, and IS256, and most belonged to the sequence type 27 subgroup, suggesting the involvement of few related clones.

FIG. 1.

Genetic relatedness between atlE_2782-3114 alleles. The evolutionary relationships were inferred using the neighbor-joining method. Branches corresponding to partitions reproduced in less than 50% bootstrap replicates are collapsed. The percentages of replicate trees in which the associated taxa clustered together in the bootstrap test (1,000 replicates) are shown next to the branches. The evolutionary distances were computed using the Nei-Gojobori method and are in units representing the number of synonymous differences per sequence. Tree branch lengths are drawn to scale. Numbers of strains are given in parentheses, atlE_CWA alleles are given in brackets (30), and STs are given in braces.