Purification and characterization of a cystatin-type cysteine proteinase inhibitor in the human hair shaft

✍ Scribed by H. Tsushima; A. Ueki; H. Mine; N. Nakajima; H. Sumi; V. K. Hopsu-Havu

• Publisher: Springer-Verlag
• Year: 1992
• Tongue: English
• Weight: 626 KB
• Volume: 284
• Category: Article
• ISSN: 0340-3696
• DOI: 10.1007/bf00372066

✦ Synopsis

We found a cysteine proteinase inhibitor in human hair shaft extract treated with 0.01 M Tris HC1 buffer, pH 8.0. A yield of 0.2 mg of purified cysteine proteinase inhibitor was obtained from 86 g of hair shaft. The cysteine proteinase inhibitor had a molecular mass of 13 kDa as determined by high-performance liquid chromatography and sodium dodecyl sulfate polyacrylamide gel electrophoresis. It was more stable to heat and pH than most proteins and had a pI of 4.7. Immunologically, its antigenicity was the same as that of cystatin A, but differed from that of cystatin B and C, and kininogen. The amino-acid sequence of the first 30 residues from the NH terminus of the inhibitor was identical to that of cystatin A from human epidermis. Hair shaft cysteine proteinase inhibitor is thus considered to be identical to epidermal cystatin A.