The role of poly-M and poly-GM sequences in the metal-mediated assembly of alginate gels

Abstract

Whilst the involvement of poly-G sequences in the formation of metal-mediated alginate gels has been previously studied in some detail, investigations into the role of poly-M and poly-GM sequences has been relatively neglected. In this regard, the binding of sodium and calcium ions to poly-M and poly-GM decamers, and their influence on chain aggregation, has been modelled by conducting a series of molecular dynamics simulations. This work complements a previous analogous study carried out for the poly-G decamer, whereby up to three strands are systematically introduced into each simulation. As in the previous study, this method allows intrinsic binding modes and interchain structural motifs to be revealed, that are consistent with those observed in available AFM images of consolidated 3-D networks. It is apparent from these studies that different sequences have different structural implications for metal-mediated chain association.

Keywords: Alginate gels; Alginate sequence; Calcium coordination; Molecular dynamics; Sodium alginate.