Weights of Proteins Determined by Light Scattering

Molecular Weights of Proteins Determined by Light Scattering, 

Comparatively few data on molecular weights are yet available, and only a few of the most recent have been determined on an absolute basis. The extensive data of Putzeys and Brosteaux (1941) are summarized in Table I. Amandin was taken as a standard protein, its molecular weight being assumed as 330,000 from sedimentation, diffusion and viscosity measurements, and the molecular weights of the other proteins were standardized with reference to it. These authors found that the turbidity/concentration ratio was a function of the concentration. For all the proteins they studied it could be described by an equation which in our notation may be written  

Bucher (1947) studied a preparation of the crystalline mercury compound of the enzyme enolase, prepared in Warburg s laboratory. He obtained a molecular weight of 66,000, using edestin as a standard protein and assuming its molecular weight to be 300,000. The value 

Molecular weights given relative to amandin as a standard protein which is taken as having a molecular weight of 330,000. 

Calibration with reference to edestin as a standard protein assumed molecular weight of edestin 300,000. 

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Table l. Molecular Weights of Proteins Determined by Light Scattering. Molecular Weight in thousands from Scattering at Ao... 

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