Jr. Ruggiero et al., CONFORMATIONAL FEATURES OF GALACTURONANS .2. CONFIGURATIONAL STATISTICS OF PECTIC POLYMERS, International journal of biological macromolecules, 17(3-4), 1995, pp. 213-218
The unperturbed dimensions of poly-alpha-D-galacturonic acid (PGA) as
a function of the degree of polymerization (n) and degree of ionizatio
n (%GalA(-)) have been determined by molecular mechanics and Monte Car
lo methods. Chain extensions appear to depend substantially on contrib
utions arising from local redistributions of charge on charged and unc
harged galacturonic acid residues. Inclusion of methyl-esterified gala
cturonic acid units results in increased chain extensions. Incorporati
on of alpha-(1 --> 2)-L-rhamnose units causes abrupt changes in chain
propagation and a reduction in calculated chain extension.