Abstract
Bacteria use flagella as propellers to move to favorable environments. Escherichia albertii, a growing cause of foodborne illness and diarrhea, is reportedly non-motile and lacks flagella on its surface. Here, we report that 27 out of 59 E. albertii strains, collected mainly from humans and birds, showed swimming motility when cultured at low osmotic pressure. The biosynthesis of flagella in E. albertii cells was induced under ambient temperature and hypoosmotic pressure: conditions which resemble aquatic environments. Flagellar induction increased E. albertii survival in the intestinal epithelial cell culture containing gentamicin. Although genes involved in chemotaxis are not present in the E. albertii genome, the addition of glutamic acid, an amino acid known to regulate the internal cell osmolarity, augmented the proportion of swimming cells by 35-fold. These results suggest that flagellar biosynthesis and motility in E. albertii cells are controlled by their internal and external osmolarity.
Highlights
Bacteria use flagella as propellers to move to favorable environments
Motility and chemotaxis are well-recognized virulence factors in many pathogens[12,13]. Bacteria, such as E. coli, contain a full suite of genes for flagellar biosynthesis and chemotaxis[9]; E. albertii has been described as non-motile and non-flagellated, and lacks the genes for chemotaxis, despite the fact that 74% of E. albertii strains possess a complete set of flagellar biosynthesis genes[3]
We demonstrate that E. albertii cells produce flagella and exhibit swimming ability when they are grown at 20 °C and under low osmotic pressure in the culture medium
Summary
Bacteria use flagella as propellers to move to favorable environments. Escherichia albertii, a growing cause of foodborne illness and diarrhea, is reportedly non-motile and lacks flagella on its surface. We report that 27 out of 59 E. albertii strains, collected mainly from humans and birds, showed swimming motility when cultured at low osmotic pressure. Genes involved in chemotaxis are not present in the E. albertii genome, the addition of glutamic acid, an amino acid known to regulate the internal cell osmolarity, augmented the proportion of swimming cells by 35-fold. These results suggest that flagellar biosynthesis and motility in E. albertii cells are controlled by their internal and external osmolarity. Most pathogenic bacteria infecting the gastrointestinal tract are motile[9] In liquid medium, they use flagella for swimming at speeds of 10–200 μm s−1. Since flagella are energetically expensive to synthesize and operate, we postulated that E. albertii produces flagella under certain conditions
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
