Dermatan sulfate-reactive lectin from chicken liver.

Area of Science:

• Biochemistry
• Glycobiology

Background:

• Dermatan sulfate (DS) is a complex glycosaminoglycan involved in various biological processes.
• Lectins are proteins that bind carbohydrates, playing roles in molecular recognition.

Purpose of the Study:

• To purify and characterize a lectin with high reactivity towards dermatan sulfate.
• To investigate the binding specificity of the purified lectin for different saccharides.

Main Methods:

• Purification of DS-lectin from chicken liver using gel filtration and affinity chromatography.
• Characterization by polyacrylamide gel electrophoresis and fluorescence spectroscopy.
• Determination of saccharide binding affinities using fluorescence-difference spectroscopy and hemagglutination inhibition tests.

Main Results:

• A single DS-lectin protein was purified, exhibiting tryptophan fluorescence quenched by specific saccharides.
• The lectin showed highest affinity for dermatan sulfate and protuberic acid, containing L-iduronic acid.
• Partially N-desulfated heparin had higher affinity than native heparin; dextran sulfate showed no affinity.
• L-iduronic acid and D-glucuronic acid residues were key binding determinants, while sulfate groups interfered.

Conclusions:

• The purified DS-lectin specifically recognizes L-iduronic acid residues and likely carboxyl groups.
• Saccharide sulfation negatively impacts the binding interaction of this DS-lectin.
• This lectin provides a valuable tool for studying DS structure and function.