Reference

Conformation, structure and activation of bovine cathepsin D

Conformation, structure and activation of bovine cathepsin D. Unfolding and refolding studies. Lah, Tamara; Drobnic-Kosorok, Marinka; Turk, Vito; Pain, Roger H. (Dep. Biochem., Jozef Stefan Inst., Ljubljana, Yugoslavia). Biochem. J., 218(2), 601-8 (English) 1984.Some commonly used reagents like 50-01-1 and 9025-26-7 are used in this experiment. CODEN: BIJOAK. ISSN: 0306-3275. DOCUMENT TYPE: Journal CA Section: 7 (Enzymes) Cathepsin D from bovine spleen is found in the cell in 2 forms, one a single polypeptide chain (mol. wt. 44,000) and the other a noncovalent complex of 2 peptides of mol. wts. 14,000 and 30,000. These correspond to the N-terminal and C-terminal regions of the single chain from which they originate. The 2 forms of the enzyme are closely similar in secondary-structure content, in arom. amino acid environment, and in denaturation behavior. The 2-chain enzyme has half the specific activity of the single-chain form. The denaturation of the single-chain cathepsin D was studied by CD, fluorescence, and enzyme activity. Activity is lost irreversibly on unfolding, but the loss of backbone ellipticity and of folded arom. environment is 75% reversible. The enzyme unfolds in 2 main stages, and the kinetics of these transitions indicate the existence of 32 intermediate forms between the native and the fully unfolded states. A further form of the enzyme exists in 0.5M guanidinium chloride. It is characterized by having an activity 40% greater than that of the native state. This increase is not reversed on removing the denaturant. The similarities between cathepsin D and pepsin are discussed. .

The use of the domestic pig as an animal model of human dry skin and for comparison of dry and normal skin properties

The use of the domestic pig as an animal model of human dry skin and for comparison of dry and normal skin properties. Bissett, Donald L.; McBridge, James F. (Miami Valley Lab., Procter and Gamble Co., Cincinnati, OH 45247, USA). J. Soc. Cosmet. Chem., 34(6), 317-26 (English) 1983. CODEN: JSCCA5.Several substances with their cas registry numbers 57-55-6 and 50-01-1 may be metioned in this study. ISSN: 0037-9832. DOCUMENT TYPE: Journal CA Section: 62 (Essential Oils and Cosmetics) Section cross-reference(s): 63 At low relative humidity, the domestic pig develops dry, scaly skin on its dorsum. The dry skin is visually similar to that seen on humans, and responds to treatment with known skin conditioners. This animal model is valuable as a tool for screening skin conditioning materials and comparing the properties of dry and normal skins. Comparison of dry and normal dorsal pig skins revealed no differences in stratum corneum thickness, turnover rate, water-binding capacity, or natural moisturizing factor content. Dry skin did have an increased nonpolar lipid content. This lipid was confined to the upper stratum corneum and was sebaceous in origin. Dry skin in the pig appears to be a phenomenon of the upper stratum corneum. .