Smart superglue in streptococci? The proof is in the pulling.

Gram-positive bacteria use reactive thioester-containing proteins to form covalent bonds, which may enable strong adhesion to host surfaces, but how these proteins selectively adhere to different surfaces is not clear. The Editors' Pick by Echelman et al. applied single-molecule force spectroscopy to show that an adhesin protein can regenerate its thioester in the absence of pulling. This selective interaction would represent a new principle of mechanical proof-reading, whereby only reactions supporting anchorage of the bacterium are maintained.