Heat shock proteins and inflammatory acne vulgaris: molecular cloning, overexpression and purification of a propionibacterium acnes GroEL and DnaK homologue.

Propionibacterium acnes is associated with inflammatory acne. The genes encoding two putative mediators of inflammation, the heat shock proteins GroEL and DnaK, were cloned from this organism and sequenced. groEL and dnaK encode proteins of 56.8 and 66.4 kDa, respectively, which show a high degree of homology (>75% similarity) to the GroEL and DnaK proteins of mycobacteria and streptomycetes. The promoter regions of both genes contain inverted repeat sequences believed to be involved in the transcriptional regulation of heat shock genes. Recombinant P. acnes GroEL and DnaK were overexpressed in Escherichia coli with C-terminal histidine tags. The recombinant proteins were purified from E. coli by metal affinity chromatography. These proteins will now be used in immunological investigations to determine their role in inflammatory acne.