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Notes from the Kjeldsen paper

According to last common ancestor analysis, cable bacteria likely descended from Deltaproteobacteria, Gammaproteobacteria, Chromatiales, and Thiotrichales.

Motility
Cable bacteria lack flagella, but are capable of motility in the form of gliding by propelling themselves forward through the excretion of substances. Their genome contains less operons related to chemotaxis than other Desulfobulbaceae, so their motility may be limited.

Notes from Scholz 2020

Methane emissions
The presence of cable bacteria can lead to a decrease in methane emissions from saturated soils. The transfer of electrons through cable bacteria allows the sulfate reduction that occurs in inundated soils to be balanced by sulfate oxidation. Oxidation is possible because of the release of electrons through the cable bacteria filaments. Through this balance, sulfate remains readily available for sulfate reducing bacteria, which out compete methanogens. This causes a decrease in production of methane by methanogens.

from Trojan

Cable bacteria can be found along a gradient of salinities; they are present in freshwater, saltwater lakes, and marine habitats.

From schloz 2019

Cable bacteria are generally found in reduced sediments.

They can be present as a single filament or as an agglomeration of filaments. Cable bacteria have been identified as being intertwined with the root hairs of aquatic plants and are present in the rhizosphere.

Notes from Bjerg

Cable bacteria have been observed to move as fast as 2.2 µm/s, with an average speed of 0.5 µm/s. Speed of motility in cable bacteria is not related to size of the bacteria. The average distance a cable bacteria glides is approximately 74 µm without interruption. Cable bacteria filaments tend to bend in half, and their movement is led by the apex of the bend as opposed to leading with one tip of the filament. Twisting to move through rotational gliding is rare, but does occur. Cable bacteria likely engage in oxygen chemotaxis, as they are observed to move when in anoxic or hypoxic environments, and cease gliding when contact with oxygen is made. Although motility is important for other microorganisms, once cable bacteria located in a place that connects oxygen to sulfide, they no longer need to move.

Another source doi:10.1128/AEM.01064-15

From Nielsen

Cable bacteria allow for long distance electron transport, which connects electron donors to electron acceptors, connecting previously separated oxidation and reduction reactions.

From Meysman

Filaments are long strings composed of cells stacked together, and can be as long as 30-70mm. Some filaments are composed of upwards of 10,000 cells.

Freshwater and marine cable bacteria have been found to be 88% similar based on 16S ribosomal RNA comparisons.

From Jiang Cells in a filament are connected by obvious junctions.

Junctions are able to withstand more force without breaking than the cells themselves. Cells on opposite sides of each junction are separated; if one cell bursts, the cell on the other side of the junction will remain intact.

Cable bacteria contain structures known as strings. Strings are located inside of ridges on the outer membrane and connect one cell to the next. Strings span the length of the entire filament uninterrupted. The width of the strings is about 20-40 nm. The size and function of a string is similar to that of a microtubule. Strings are thought to serve as a structural foundation for filaments and play a key role in maintaining filament shape, especially during growth.

added in this source too