The choice of EM technique might have been wrong in visualizing the so-called oscillin fibrils, but was effective in visualizing membrane structures. The absence of “oscillin” was based on the genomic analysis but not on EM images. In fact, “oscillin” is a glycine-rich large protein which is poorly conserved in bacteria. In the reported case of P. uncinatum, oscillin might be important in forming fibrils, but in other organisms, other proteins could function as surface fibrils aligning the flow of slime. We agree that the method of fixation was not good for preserving surface structures such as oscillin fibrils, if present.
Overall, this study presents observations related to slime-mediated motility on multiple scales (molecular, single-filament and colony), and integrates these findings into a coherent model for the relationship between the cellular organization and the behavior of the colony.