Conformational features of carrabiose polymers: I. Configurational statistics of kappa-carrageenan.
Potential energy functions evaluating both repulsive-attractive van der Waals non-bonding interactions and electrostatic interactions have been used to evaluate the conformational energies of the repeating units of the kappa-carrageenan polymers. Structural parameters have been obtained by minimization MNDO procedures (MOPAC). Energy maps have been calculated for the (1-3) alpha-D-galactose-4-sulphate (GS) and the (1-4)-3,6-anhydro-alpha-D-galactose (A) residues, taking into account the conformational freedom of the sulphate group. The configurational statistics of the random coiled kappa-carrageenan chain have been explored, disclosing a highly flexible character, which can mainly be ascribed to the random occurrence of two different conformers of the GS-A dimeric unit.
Urbani
R
R
Department of Biochemistry, Biophysics and Macromolecular Chemistry, University of Trieste, Italy.
Di Blas
A
A
Cesàro
A
A
D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002351:Carrageenan / Q000737:chemistry*; D003198:Computer Simulation; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000737:chemistry*
D009844:Oligosaccharides; C080061:carrabiose; D002351:Carrageenan