Open AccessBifurcated Hydrogen Bonds and the Fold Switching of Lymphotactin
Author(s) -
Prabir Khatua,
Alan Ray,
Ulrich H. E. Hansmann
Publication year - 2020
Publication title -
the journal of physical chemistry. b
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.864
H-Index - 392
eISSN - 1520-6106
pISSN - 1520-5207
DOI - 10.1021/acs.jpcb.0c04565
Subject(s) - hydrogen bond , fold (higher order function) , chemistry , replica , crystallography , stereochemistry , molecule , computer science , organic chemistry , art , visual arts , programming language
Lymphotactin (Ltn) exists under physiological conditions in an equilibrium between two interconverting structures with distinct biological functions. Using replica-exchange-with-tunneling, we study the conversion between the 2-folds. Unlike previously proposed, we find that the fold switching does not require unfolding of lymphotactin but proceeds through a series of intermediates that remain partially structured. This process relies on two bifurcated hydrogen bonds that connect the β 2 and β 3 strands and ease the transition between the hydrogen bond pattern by which the central three-stranded β-sheet in the two forms differs.