[Chemical properties of rat thymus agglutinating substance].

A substance reacting with sheep red blood cells and rabbit IgG was isolated from the rat thymocytes and calf thymus as a homogeneous preparation. Some chemical properties of this substance were studied. The molecular weight of the agglutinating substance was found to be 12300 according to the SDS-gel electrophoresis data. The infrared spectra show that this substance contains peptide bonds and a carbohydrate component. The amide II absorption band observed in the infrared spectrum disappears after treatment of the agglutinating substance with immobilized pronase. The treatment with immobilized pronase leads to degradation of this substance into two components detected by thin layer chromatography and to the loss of its agglutinating properties. Hexose was determined in the substance with an anthrone reagent. This substance is supposed to be a low-molecular glycoprotein.