Analysis of cellular fatty acids used as a taxonomic tool to differentiate Erwinia species
The genus Erwinia has been divided into three clusters, respectively the E. herbicola, E. amylovora and the E. carotovora groups. By using gas-liquid chromatography techniques, the authors have studied separately the cellular fatty acids of Erwinia species belonging to the Amylovora group (E. amylovora (EPPO A2 quarantine pest), E. nigrifluens, E. quercina, E. rubrifaciens, E. salicis and E. tracheiphila), and the Herbicola group (E. herbicola, E. ananas, E. stewartii (EPPO A2 quarantine pest), and E. uredova). For each species several strains, grown on King's medium B agar during 1,3 or 6 days at 28 øC, have been analysed. It was found that the physiological age of the cells could affect fatty acid composition. However, within these two groups, the authors were able to establish dichotomous keys based on differences in cellular fatty acid composition, in order to differentiate the species. In addition, they could also identify changes in fatty acid composition which could readily distinguish E. herbicola and E. stewartii from E. amylovora. The authors concluded that analysis of cellular fatty acid can be used as a taxonomic tool to distinguish species of bacteria and as a confirmatory technique, but that further studies should be carried out on a wider number of strains for each Erwinia species.
Sources
Wells, J.M.; van der Zwet, T.; Hale, C.N. (1994) Differentiation of Erwinia species in the "Amylovora" group by class analysis of cellular fatty acids.
Journal of Phytopathology, 140 (1), 31-38.
Wells, J.M.; van der Zwet, T.; Butterfield, J.E. (1994) Differentiation of Erwinia species in the "Herbicola" group by class analysis of cellular fatty acids.
Journal of Phytopathology, 140 (1), 39-48.