Growth of Flagellar Filaments of Escherichia coli Is Independent of Filament Length

Bacterial flagellar filaments grow at their distal ends, from flagellin that travels through a central channel ∼2 nm in diameter. The flagellin is extruded from the cytoplasm by a pump powered by a proton motive force (PMF). We measured filament growth in cells near the mid-exponential-phase with fl...

Full description

Saved in:
Bibliographic Details
Published in:Journal of Bacteriology 2012-05, Vol.194 (10), p.2437-2442
Main Authors: Turner, Linda, Stern, Alan S, Berg, Howard C
Format: Article
Language:English
Subjects:
arabinose
Bacteriological Techniques
Bacteriology
Biological and medical sciences
cell growth
Chromosomes
cytology
Cytoplasm
Dyes
E coli
Escherichia coli
Escherichia coli - cytology
Escherichia coli - physiology
Flagella
Flagella - physiology
flagellin
Flagellin - genetics
Flagellin - metabolism
Fluorescent Dyes
Fundamental and applied biological sciences. Psychology
Gene Expression Regulation, Bacterial
Gene Expression Regulation, Bacterial - physiology
genetics
Image Processing, Computer-Assisted
Maleimides
Melanins
metabolism
Microbiology
Miscellaneous
operon
Organic Chemicals
physiology
plasmids
proton pump
Staining and Labeling
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Bacterial flagellar filaments grow at their distal ends, from flagellin that travels through a central channel ∼2 nm in diameter. The flagellin is extruded from the cytoplasm by a pump powered by a proton motive force (PMF). We measured filament growth in cells near the mid-exponential-phase with flagellin bearing a specific cysteine-for-serine substitution, allowing filaments to be labeled with sulfhydryl-specific fluorescent dyes. We labeled filaments first with a green maleimide dye and then, following an additional period of growth, with a red maleimide dye. The contour lengths of the green and red segments were measured. The average lengths of red segments (∼2.3 μm) were the same regardless of the lengths of the green segments from which they grew (ranging from less than 1 to more than 9 μm in length). Thus, flagellar filaments do not grow at a rate that decreases exponentially with length, as formerly supposed. If flagellar filaments were broken by viscous shear, the broken filaments continued to grow. Identical results were obtained whether flagellin was expressed from fliC on the chromosome under the control of its native promoter or on a plasmid under the control of the arabinose promoter.
ISSN:0021-9193
1098-5530
1067-8832
DOI:10.1128/jb.06735-11