The importance of motility and chemotaxis for extra-animal survival of Salmonella enterica serovar Typhimurium and Dublin

Abstract

This study investigated the importance of flagella and motility of Salmonella enterica serovar Typhimurium and Dublin in models of extra-animal survival. The study was performed using transposon mutants in flagella genes fliC and fljB and in chemotaxis genes cheA, cheB and cheR. Flagella and chemotaxis were found to be of minor importance for attachment to plant leaves, survival in liquid manure and interaction with the nematode C. elegans, while differences were observed between the fliC mutant and the wild-type strain of S. Dublin in interactions with amoebae. The study shows that flagella and chemotaxis play a minor role in extra-animal survival of these two serovars of Salmonella under the conditions tested. Extra-animal survival is important in the full infection cycle for zoonotic salmonellae. Such serovars are motile. Even though the current study was only based on the characterization of two serovars, it strongly suggests that motility and chemotaxis are of minor importance during the spread of Salmonella from one animal to the next through the external environment.