ABSTRACT
Within the genus, species have been traditionally differentiated into two groups, the “classical” or “dairy” and the “cutaneous” propionibacteria. While molecular analyses have revealed that the phylogenetic relationships amongst propionibacteria do not exactly mirror their classiŠcation based on habitat (Figure 13.1), it is still a useful and convenient way to group the species. The “classical” or “dairy” propionibacteria includes the species P. freudenreichii, P. jensenii, P. thoenii, and P. acidipropionici, which are isolated mainly from cheese and other dairy products and are also used as starter cultures by the dairy industry and
13.1 Introduction ..................................................................................................................................................................... 137 13.1.1 ClassiŠcation, Morphology, and Biology ............................................................................................................ 137 13.1.2 Propionibacteria and Disease .............................................................................................................................. 139 13.1.3 Pathogenic Features of Propionibacteria ............................................................................................................. 140 13.1.4 Diagnosis of Human Propionibacterial Infections ...............................................................................................141
