Structure of a polysaccharide protein complex.

Abstract
The fundamental structure of a polysaccharide protein complex from rib costal cartilage was elucidated primarily by physical chemical methods. The molecular weight of the chondroitin 4-sulfate side chains was found to be of the order of 13,000 and was rather monodisperse. The failure to observe a random distribution of molecular weights sug-gests that the polymer is synthesized in a multichain condensation step on a polypeptide matrix, with a number of equivalently reactive sites available for polymerization. The minimal polypeptide unit has a mol-ecular weight of 10,600 and 5 [plus or minus] 1 reactive serines. The initial carbohydrate residue attached to serine is [beta]-D-xylopyranose, which may serve a recognition function.