The cariogenic bacterium Streptococcus mutans uses adhesin P1 to adhere to tooth surfaces, extracellular matrix components, and other bacteria. The N terminus forms a stabilizing scaffold by wrapping behind the base of P1's elongated stalk and physically 'locking' it into place. It is suggested that the N-terminal has such a pronounced impact on P1 immunogenicity, antigenicity, folding, stability, and adherent function [1].

1: An intramolecular lock facilitates folding and stabilizes the tertiary structure of Streptococcus mutans adhesin P1. Heim KP, Crowley PJ, Long JR, Kailasan S, McKenna R, Brady LJ; Proc Natl Acad Sci U S A. 2014;111:15746-15751. PMID:25331888