Chemistry: Cohn and Conant the Molecular Weights of Proteins in Phenol
نویسنده
چکیده
I. A large body of evidence has been accumulated in recent years which indicates that proteins have very large molecular weights. The molecular weight of egg albumin, the smallest of the proteins that have been adequately studied, is approximately 34,000. This estimate was made by S0rensen14 on the basis of osmotic pressure measurements in which he corrected for the unavoidable influence of inorganic salts, and is entirely confirmed by analyses of the sulfur and sulfide sulfur and of certain of the amino acids of which the molecule is composed.3 Since egg albumin contains 1.23% of tryptophane5 the smallest weight of a gram molecule that could contain one gram molecule of this amino acid would be approximately 16,600. The sulfide sulfur and sulfur contents'0 suggest a molecular weight of twice this minimal molecular weight as the calculations in table 1 demonstrate. The analytical and physical-chemical measurements thus lead to the same result and leave little doubt regarding the size of this protein.
منابع مشابه
Studies in the Physical Chemistry of the Proteins. v. the Molecular Weights of the Proteins.* Part 1. the Minimal Molecular Weights of Certain Proteins
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