Biophysics and Physicobiology
Online ISSN : 2189-4779
Review Article
Cross-kymography analysis to simultaneously quantify the function and morphology of the archaellum
Yoshiaki KinositaTakayuki Nishizaka
Author information
JOURNALS FREE ACCESS

Volume 15 (2018) Pages 121-128

Details
Download PDF (4171K) Contact us
Abstract

In many microorganisms helical structures are important for motility, e.g., bacterial flagella and kink propagation in Spiroplasma eriocheiris. Motile archaea also form a helical-shaped filament called the ‘archaellum’ that is functionally equivalent to the bacterial flagellum, but structurally resembles type IV pili. The archaellum motor consists of 6–8 proteins called fla accessory genes, and the filament assembly is driven by ATP hydrolysis at catalytic sites in FlaI. Remarkably, previous research using a dark-field microscopy showed that right-handed filaments propelled archaeal cells forwards or backwards by clockwise or counterclockwise rotation, respectively. However, the shape and rotational rate of the archaellum during swimming remained unclear, due to the low signal and lack of temporal resolution. Additionally, the structure and the motor properties of the archaellum and bacterial flagellum have not been precisely determined during swimming because they move freely in three-dimensional space. Recently, we developed an advanced method called “cross-kymography analysis”, which enables us to be a long-term observation and simultaneously quantify the function and morphology of helical structures using a total internal reflection fluorescence microscope. In this review, we introduce the basic idea of this analysis, and summarize the latest information in structural and functional characterization of the archaellum motor.

Information related to the author
© 2018 THE BIOPHYSICAL SOCIETY OF JAPAN
Previous article Next article

Recently visited articles
Predecessor

BIOPHYSICS

feedback
Top