The carbohydrate composition of the extracellular sulphated polysaccharide obtained from cultures of the unicellular red alga Porphyridium was determined. The polysaccharide was separated by anion-exchange chromatography into eight fractions. The major carbohydrate-containing fractions, accounting for ca 89% of the total carbohydrates, were the 0.5, 1.0 and 2.0 M NaCl fractions and the hot urea fraction. The NaCl-eluted fractions showed very similar neutral sugar compositions, with some differences in the contents of sulphate and uronic acid, which increased from the 0.5 M to the 2 M NaCl fraction. The hot urea fraction was apparently a xylan (about 86% xylose) and accounted for about 72% of the protein found in the whole polysaccharide. These findings indicate the presence of at least two different polysaccharides, one of which seems to be a proteoglycan. Amino acid analysis of the latter fraction was performed.
- Porphyridium sp., unicellular red algae
- amino acid analysis.
- anion-exchange chromatography
- gel-permeation chromatography
ASJC Scopus subject areas
- Molecular Biology
- Plant Science