Polyglutamine β-sheet aggregates are associated with the derangement of Huntington's disease. The effect of cooperativity of the H-bond network formed by both backbone and side chain groups is expected to be important for the structure and energetics of the aggregates. So far, no direct description and/or quantification of the effect is yet available. By performing DFT and hybrid DFT/MM simulations of polyglutamine β-sheet structures in vacuo and in aqueous solution, we observe that the cooperativity of glutamine side chains affects both the directions perpendicular and parallel to the backbone. This behavior is not usually observed in β sheets and may provide significant extra-stabilization together with explaining some of the unique properties of polyglutamine aggregation.
Hydrogen Bonding Cooperativity in polyQ beta-Sheets from First Principle Calculations
Pastore A;
2010
Abstract
Polyglutamine β-sheet aggregates are associated with the derangement of Huntington's disease. The effect of cooperativity of the H-bond network formed by both backbone and side chain groups is expected to be important for the structure and energetics of the aggregates. So far, no direct description and/or quantification of the effect is yet available. By performing DFT and hybrid DFT/MM simulations of polyglutamine β-sheet structures in vacuo and in aqueous solution, we observe that the cooperativity of glutamine side chains affects both the directions perpendicular and parallel to the backbone. This behavior is not usually observed in β sheets and may provide significant extra-stabilization together with explaining some of the unique properties of polyglutamine aggregation.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.