Correction to "self-assembly of minimal peptoid sequences"

It has come to our attention that some of our cryo-electron microscopy (cryo-EM) images actually show ice contamination, (1) instead of the soft matter aggregates originally indicated in our publication. The images only relate to counterexample peptoid sequences that did not properly assemble (originally Figures 3D–K and S5E–G, I–M, and P). As such, our main finding of an ultrashort water-soluble tripeptoid assembling into ordered nanofibers is not changed. Our overall conclusions based on complementary cryo-EM, DLS, CAC, and fluorescence spectroscopy measurements are also unaffected. Nonetheless, the figures indicated and associated text require correction. In re-examining our cryo-EM data set, we found micrographs showing additional structures that are unlikely to be contaminants, which we previously took as less representative. Like the artifacts, the structures now identified are also irregular and consist of an ensemble of sizes centered around a mean. Incidentally, the mean sizes of these structures (50–250 nm in diameter, depending on sequence) fit better with our complementary DLS results—no agglomeration effect of individual 5–20 nm ice artifacts is needed anymore to reconcile the sizes measured by EM and DLS.