Concanavalin molecular weight

Suppressor lymphocytes control immune responses in part by secretion of an antigegjspecific factor which is not active across histocompatibility barriers. This product has a molecular weight between 35,000 and 55,000 daltons and can be completely absorbed with an alloantiseruij2 specific for the I region of the major histocompatibility complex. A soluble immune response suppressor (SJ S) is produced by concanavalin A-stimulated murine splenic lymphocytes and inhibits plaque-fcjjjming responses of B lymphocytes and cytotoxic lymphocyte responses t allo-antigens. SIRS has a molecular weight between 48,000 and 67,000, does... 

From the observation that the partitioning behavior of each protein was not affected by the presence of the others (38, 49), Goklen and Hatton resolved a mixture of cytochrome-c, ribonuclease-A and lysozyme, three low molecular weight proteins comprised in the range 12.4 - 14.3 kDa. With the same reversed micellar phase, Woll et (49) showed that the selectivity of extraction between ribonuclease-A and concanavalin-A could be modulated by vaiying the surfactant concentration a 40% enhancement... 

Its mechanism of action, however, is not completely elucidated. Kamakura et al. [94] studied the effects of stem bromelain on the plasma kallikrein system, bradykinin levels and plasma exudation at the inflammatory site in rats with a kaolin-induced inflammation of an air pouch. Bromelain caused a dose-dependent decrease of bradykinin levels (measured with the method of Minami et al. [95]) at the inflammatory site and a parallel decrease of the prekallikrein levels in sera [88]. Plasma exudation was also reduced dose-dependently. Bradykinin-degrading activity in sera was elevated after bromelain treatment, but not in the pouch fluid. The authors conclude that bromelain inhibits plasma exudation through inhibition of the bradykinin generation at the inflammatory site via depletion of the plasma kallikrein system. Bromelain also shows a dose-dependent analgesic effect in concanavalin A-injected paws of 5.6 mg/kg i.v.), considered to be due to decrease of high molecular weight kininogen [96]. 

A major group of glycoproteins, which have a high molecular weight and stain only faintly with Coomassie Blue, but bind to concanavalin A, have been identified in the plasma membranes of Chinese hamster fibroblasts. Their presence is only revealed by two-dimensional electrophoresis and not by conventional electrophoretic techniques. The alteration of membrane components of hamster-kidney fibroblasts transformed by Rous sarcoma virus is expressed in an increase in the levels of three glycoproteins, when compared with.those of control cells. The structure (24) of the major cell-surface glycoprotein from hamster-embryo fibroblasts has been established. ... 

Concanavalin A.—The interactions of metal ions with the transition-metal SI, and calcium-ion, S2, binding sites of concanavalin A have attracted some attention. Each protomer of molecular weight 27 000 has one SI and one S2 site and the protein exists in a dimeric form, pH < 5.5, and tetrameric form, pH > 7.0. Metal ion binding has been studied using the fluorescence quenching of 4-methyl-umbelliferyl-a-D-mannopyranoside (MUM), a sugar residue which binds to the protein in its various metallated forms ... 

Affinity chromatography on agarose-concanavalin A has shown that a significant fraction of the high-molecular-weight form of adrenocorticotrophic hormone from human pituitaries is a glycoprotein. ... 

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