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PubMed · 952948

Urea-extractable protein from human epidermis.

J Baynes·M Levine
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Abstract

The major protein fraction extracted from human epidermis by urea has the following characteristics: (1) A molecular weight of approximately 600 000. (2) A copper content of 0.03% giving a minimum molecular weight of 212 000. (3) A non-protein moiety indicated by (a) protein/dry weight ratio (b) anomalous ultraviolet absorption spectrum (c) high-voltage electrophoresis after mild alkaline or acid treatment (d) an excess of imidazole groups by Pauly reaction compared with the number of histidine residues by amino acid analysis. The non-protein component is not urocanic acid or RNA as has been reported (Bernstein, I.A. (1970), J. Soc. Cosmet, Chem. 21, 583-594 and Sibrack, L. A., Gray, R. H. and Bernstein, I. A. (1974), J. Invest. Dermatol. 62, 394-405). (4) The presence of interchain disulphide linkages indicated by polyacrylamide gel electrophoresis in sodium dodecyl sulphate with and without beta-mercaptoethanol. (5) Polyacrylamide gel electrophoresis in presence and absence of 6 M urea suggests that aggregates are broken down in urea.

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Amino AcidsCopperHistidineHumansMetalloproteinsMolecular WeightProtein BindingSkinSpectrophotometry, UltravioletUreaJournal Article

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J Baynes, M Levine. 1976-07-19. Urea-extractable protein from human epidermis.. https://doi.org/10.1016/0005-2795(76)90166-5

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