Related Experiment Video
Updated: Mar 22, 2026
07:59
Investigating Flagella-Driven Motility in Escherichia coli by Applying Three Established Techniques in a Series
Published on: May 10, 2020
8.9K
Motility of Electric Cable Bacteria
Jesper Tataru Bjerg1, Lars Riis Damgaard2, Simon Agner Holm2
1Center for Geomicrobiology, Department of Bioscience, Aarhus University, Aarhus, Denmark Section for Microbiology, Department of Bioscience, Aarhus University, Aarhus, Denmark jjbjerg@bios.au.dk.
Applied and Environmental Microbiology
|April 17, 2016
Summary
Cable bacteria exhibit gliding motility, moving in loops and responding to chemical gradients. This movement helps them maintain electrical connections between electron donors and acceptors in dynamic sediments.
Area of Science:
- Microbiology
- Geobiology
- Environmental Science
Background:
- Cable bacteria are filamentous microorganisms known to couple redox reactions over centimeter distances.
- Their motility in sediment environments has been previously suggested but not directly observed.
Purpose of the Study:
- To investigate and characterize the motility of cable bacteria.
- To understand how motility contributes to their ecological function in sediment environments.
Main Methods:
- Time-lapse microscopy was employed to observe cable bacteria on surfaces.
- Analysis included measuring motility speed, direction reversals, and response to chemical gradients.
Main Results:
- Cable bacteria demonstrated gliding motility with variable speeds (0.5 ± 0.3 µm s⁻¹) and frequent direction reversals (155 ± 108 s).
- Filaments formed loops and twisted structures, indicating helical rotation.
- Bacteria actively responded to chemical gradients, accumulating at the oxic-anoxic interface and forming structures that connected sulfide sources to oxygenated areas.
Conclusions:
- Motility is crucial for cable bacteria to establish and maintain optimal electrical connections between distant electron donors and acceptors.
- This behavior allows cable bacteria to thrive in dynamic sediment environments by adapting to changing chemical conditions.
Related Concept Videos
01:18Other Unique Bacteria
534
Magnetic bacteria exhibit a directed movement called magnetotaxis, driven by structures called magnetosomes. These magnetosomes consist of chains of magnetic particles made of either magnetite (Fe₃O₄) or greigite (Fe₃S₄) and are organized in a linear conformation by a protein scaffold within invaginations of the cell membrane. The bacteria align along the north–south magnetic field lines, much like a compass needle. They are typically microaerophilic or anaerobic...
534
01:18Flagella and Motility in Bacteria
4.8K
Flagella are specialized, thread-like structures that extend from a bacteria's cell envelope. They play a crucial role in motility and chemotaxis. Their structural organization and functioning exemplify sophisticated biological engineering, enabling bacterial survival and adaptability in diverse environments.Structure of the FlagellumA bacterial flagellum consists of three key components: the filament, the hook, and basal body. The filament, a long, helical structure composed of repeating...
4.8K
01:10Intracellular Movement of Viruses and Bacteria
3.8K
Intracellular bacteria and viruses often comprise a group of highly infectious pathogens that can cause several diseases. Bacterial pathogens include those belonging to the genus Rickettsia responsible for conditions such as rocky mountain spotted fever and the Mediterranean spotted fever; Chlamydia, a genus responsible for a sexually transmitted disease; Coxiella burnetii, an agent responsible for Q fever. Viral pathogens include vaccinia—a poxvirus, and herpes simplex virus—a...
3.8K
01:27Chemotaxis in E. coli
1.2K
Chemotaxis in Escherichia coli is a sensory-driven motility mechanism that enables bacteria to navigate chemical gradients, moving toward beneficial environments while avoiding harmful conditions. This process relies on a signal transduction system integrating external chemical cues with flagellar motor control.Chemoreceptors and Signal DetectionE. coli detects chemical gradients through methyl-accepting chemotaxis proteins (MCPs), which are membrane-bound chemoreceptors that sense attractants...
1.2K
01:24Bacterial Phylum Tenericutes
578
The phylum Tenericutes, which includes the single class Mollicutes, comprises bacteria that lack cell walls. The term "Mollicutes" derives from the Latin word mollis, meaning "soft." These organisms are among the smallest known and are commonly referred to as mycoplasmas due to the prominence of the genus Mycoplasma, which includes well-known human pathogens. Despite their inability to stain gram-positively (a result of their lack of cell walls), mycoplasmas are phylogenetically related to the...
578
01:24Microtubules in Cell Motility
5.0K
Microtubules are thick hollow cylindrical proteins that help form the cytoskeleton. Microtubules have varied roles in the cell. These filaments help form cellular appendages like cilia and flagella, which are responsible for locomotion. The cilia arise from basal bodies, separated from the main body by a membrane-like structure forming the transition zone. This zone is the gate for the entry of lipids and proteins, creating a unique composition of lipids and proteins in the ciliary membrane and...
5.0K