A review of recent taxonomic changes in seven genera of bacteria commonly found in foods

Abstract

The purpose of this review is to call attention to the new approaches now in use that classify bacteria primarily on the basis of phylogenetic criteria. The primary laboratory methods for ascertaining phylogenetic relationships entail the use of 16S rRNA and DNA sequence comparisons. These methods have been applied to some long-established genera of bacteria of importance in foods, and seven genera (Bacillus, Clostridium, Flavobacterium, Micrococcus, Pseudomonas, Staphylococcus, and Xanthomonas) are summarized in this review. Some 121 species and strains from these seven genera were recently transferred to 36 newly created genera. The new genera consist of general environmental contaminants and some food spoilage species. To date, significant taxonomic changes have not been reported for foodborne pathogens. These taxonomic shifts need to be examined with respect to the utility of widely used microscopic, cultural, and serologic methods for future use in food microbiology. Phylogeny-based detection and identification methods for foodborne bacteria must be further developed for larger numbers of foodborne genera in order to keep up with the current trends in taxonomy.