Propulsion of African trypanosomes is driven by bihelical waves with alternating chirality separated by kinks.
Trypanosoma brucei, a parasitic protist with a single flagellum, is the causative agent of African sleeping sickness. Propulsion of T. brucei was long believed to be by a drill-like, helical motion. Using millisecond differential interference-contrast microscopy and analyzing image sequences of cultured procyclic-form and bloodstream-form parasites, as well as bloodstream-form cells in infected mouse blood, we find that, instead, motility of T. brucei is by the propagation of kinks, separating left-handed and right-handed helical waves. Kink-driven motility, previously encountered in prokaryotes, permits T. brucei a helical propagation mechanism while avoiding the large viscous drag associated with a net rotation of the broad end of its tapering body. Our study demonstrates that millisecond differential interference-contrast microscopy can be a useful tool for uncovering important short-time features of microorganism locomotion.
Rodríguez
Jose A
JA
Department of Surgery, Division of Surgical Oncology, Molecular Biology Institute, The David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA.
Lopez
Miguel A
MA
Thayer
Michelle C
MC
Zhao
Yunzhe
Y
Oberholzer
Michael
M
Chang
Donald D
DD
Kisalu
Neville K
NK
Penichet
Manuel L
ML
Helguera
Gustavo
G
Bruinsma
Robijn
R
Hill
Kent L
KL
Miao
Jianwei
J
D000818:Animals; D002465:Cell Movement; D002478:Cells, Cultured; D005407:Flagella / Q000502:physiology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008853:Microscopy / Q000379:methods; D014346:Trypanosoma brucei brucei / Q000166:cytology / Q000502:physiology*; D014353:Trypanosomiasis, African / Q000382:microbiology*