Characterization of enolase fromClostridium difficile

We have isolated and purified enolase fromClostridium difficile. This is the first report of an enolase of theClostridium genus, and in general its characteristics resemble those described previously for other species, except that it is extremely thermostable. Interestingly,C. difficile enolase has an octameric structure (approximately 300 kDa on native PAGE, 50 kDa on SDS PAGE, and 338 kDa by gel filtration). Enolases fromC. sordellii andC. bifermentans have been partially purified and have a molecular weight similar to that ofC. difficile. It may be that this large size is common for enolases isolated from bacteria of theClostridium genus.