High-sulfur protein subunits in keratins
Humeniuk, V.V.; Robak, V.I.
Ukrainskii Biokhimicheskii Zhurnal 65(6): 3-10
1993
ISSN/ISBN: 0201-8470 PMID: 7519377 Document Number: 417935
The quaternary structure of keratins contains a definite amount (to 40%) of protein-subunits with higher content of sulphur composing cystine, cysteine and other derivatives of these amino acids. These proteins are characterized by low molecular weight (to 30 kDa), significant heterogeneity and disordered, most probably, globular ternary structure in a free state. Being a constituent of the amorphous part of keratin (the so-called "matrix") and forming numerous intra- and intermolecular disulphide links, they stabilize the quaternary structure and promote resistance of keratins in solution and action of proteolytic enzymes.