Identification of Uronic‐Acid‐Rich Protein as Urinary Bikunin, the Light Chain of Inter‐α‐Inhibitor

摘要: Uronic-acid-rich protein (UAP) is a urinary glycoprotein that inhibits calcium oxalate crystallization in vitro. It shows structural similarity to bikunin, component of inter-α-inhibitor (IαI) known for its inhibition the action many serine proteinases like trypsin and chymotrypsin. To clarify relationship between these macromolecules, UAP, IαI, plasma bikunin were purified studied. Their inhibitory activity was assayed before after treatment with chondroitinase AC pronase. molecular mass determined by using SDS/PAGE treatments. Polyclonal antibody used on Western blots immunological identification. The partial amino acid sequence UAP determined. Also, antitryptic measured compared which responsible antiprotease IαI. exhibited strong activity. IαI both bikunins less inhibitory. Chondroitinase had no effect proteins even when their changed. However, pronase treatment, completely destroyed. found be 0.78 U/mg lower than about 1.9 U/mg. On blotting, immunoreacted bikunins. Partial confirmed identity as bikunin.