Fig. 4.

A cargo-transporter relationship exists between nonmotile and gliding bacteria of the human microbiome. (A) Seven different species of nonmotile bacteria were carried along the surface of C. gingivalis cells, moving from one end of the cell to the other. The images have been aligned to reveal the motion of the cargo relative to the C. gingivalis cell. The raw data are shown in Movies S6–S12. (Scale bar: 1 µm.) The eight bacteria shown in the matrix are some of the abundant microbial species found in a human subgingival biofilm. (B) The trajectory of the nonmotile bacterium P. oris transported along the length of a C. gingivalis cell shown as a detailed example of the cargo-transporter relationship described above. P. oris moved from one pole to the other and looped back after it reached a pole. The C. gingivalis cell is outlined by a dotted line; the color map indicates time. Experiments were done at room temperature on glass.