Cholera stool bacteria repress chemotaxis to increase infectivity.
Factors that enhance the transmission of pathogens are poorly understood. We show that Vibrio cholerae shed in human 'rice-water' stools have a 10-fold lower oral infectious dose in an animal model than in vitro grown V. cholerae, which may aid in transmission during outbreaks. Furthermore, we identify a bacterial factor contributing to this enhanced infectivity: The achievement of a transient motile but chemotaxis-defective state upon shedding from humans. Rice-water stool V. cholerae have reduced levels of CheW-1, which is essential for chemotaxis, and were consequently shown to have a chemotaxis defect when tested in capillary assays. Through mutational analyses, such a state is known to enhance the infectivity of V. cholerae. This is the first report of a pathogen altering its chemotactic state in response to human infection in order to enhance its transmission.
Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA 02111, USA.
Susan M
SM
Butler
Eric J
EJ
Nelson
Nityananda
N
Chowdhury
Shah M
SM
Faruque
Stephen B
SB
Calderwood
Andrew
A
Camilli
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002633:Chemotaxis / Q000235:genetics; D002771:Cholera / Q000382:microbiology*; D018562:Disease Transmission, Infectious; D015536:Down-Regulation; D005243:Feces / Q000382:microbiology*; D005798:Genes, Bacterial; D017384:Sequence Deletion; D014734:Vibrio cholerae / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D041241:Vibrio cholerae O1 / Q000472:pathogenicity
D001426:Bacterial Proteins; C051236:CheW protein, Bacteria