Chapter 11
Leptospira spp. Toolbox for Chemotaxis Assay
Ambroise Lambert
Abstract
A toolbox for chemotaxis assay adapted to Leptospira spp. has emerged in the recent years: soft agar assay,
capillary assay, and videomicroscopy tracking. Those methods allow to demonstrate chemotaxis defect,
identify diverse chemoattractants, or decipher motile behavior quantitatively. These experiments have
demonstrated a role of motility and potentially chemotaxis in leptospirosis pathogenesis. We describe
extensively the methods and provide the key steps to use this toolbox.
Key words Chemotaxis, Leptospirosis, Leptospira interrogans, Capillary assay, Videomicroscopy,
Motility
1 Introduction
Leptospira spp. are bacteria with saprophytic and pathogenic species
belonging to the phylum of spirochetes. Pathogenic Leptospira are
the causative agents of leptospirosis. The zoonotic disease mostly
carried and disseminated by rodents represents over a million cases
per year according to the most recent estimation [1]. Carriers are
contaminated at the kidney level and disseminate the bacteria in the
environment through their urine. Human infection mostly occurs
by infection through contaminated soil or water during recreational activities or in poor sanitary conditions [2]. Pathogenic Leptospira strains are highly motile which enable them to quickly
disseminate and reach target organs [3, 4]. The motility and possibly the chemotaxis of Leptospira spp. have been demonstrated to
play a critical role in pathogenesis [5–9].
In recent years, cryotomography combined with genetics,
videomicroscopy, and biochemistry has allowed to decipher the
motility of Leptospira spp. [10, 11]. Leptospira spp. are thin
(0.1–0.3 μm) and elongated (10–20 μm) helically shaped bacteria,
while other spirochetes like Borrelia burgdorferi are flat wave
shaped. This morphology combined with periplasmic flagella allows
them to swim in viscous media where most peritrichous flagellated
Nobuo Koizumi and Mathieu Picardeau (eds.), Leptospira spp.: Methods and Protocols, Methods in Molecular Biology, vol. 2134,
https://doi.org/10.1007/978-1-0716-0459-5_11, © Springer Science+Business Media, LLC, part of Springer Nature 2020
123
Leptospira spp. Toolbox for Chemotaxis Assay
Ambroise Lambert
Abstract
A toolbox for chemotaxis assay adapted to Leptospira spp. has emerged in the recent years: soft agar assay,
capillary assay, and videomicroscopy tracking. Those methods allow to demonstrate chemotaxis defect,
identify diverse chemoattractants, or decipher motile behavior quantitatively. These experiments have
demonstrated a role of motility and potentially chemotaxis in leptospirosis pathogenesis. We describe
extensively the methods and provide the key steps to use this toolbox.
Key words Chemotaxis, Leptospirosis, Leptospira interrogans, Capillary assay, Videomicroscopy,
Motility
1 Introduction
Leptospira spp. are bacteria with saprophytic and pathogenic species
belonging to the phylum of spirochetes. Pathogenic Leptospira are
the causative agents of leptospirosis. The zoonotic disease mostly
carried and disseminated by rodents represents over a million cases
per year according to the most recent estimation [1]. Carriers are
contaminated at the kidney level and disseminate the bacteria in the
environment through their urine. Human infection mostly occurs
by infection through contaminated soil or water during recreational activities or in poor sanitary conditions [2]. Pathogenic Leptospira strains are highly motile which enable them to quickly
disseminate and reach target organs [3, 4]. The motility and possibly the chemotaxis of Leptospira spp. have been demonstrated to
play a critical role in pathogenesis [5–9].
In recent years, cryotomography combined with genetics,
videomicroscopy, and biochemistry has allowed to decipher the
motility of Leptospira spp. [10, 11]. Leptospira spp. are thin
(0.1–0.3 μm) and elongated (10–20 μm) helically shaped bacteria,
while other spirochetes like Borrelia burgdorferi are flat wave
shaped. This morphology combined with periplasmic flagella allows
them to swim in viscous media where most peritrichous flagellated
Nobuo Koizumi and Mathieu Picardeau (eds.), Leptospira spp.: Methods and Protocols, Methods in Molecular Biology, vol. 2134,
https://doi.org/10.1007/978-1-0716-0459-5_11, © Springer Science+Business Media, LLC, part of Springer Nature 2020
123