The α-β Transformation in keratin

Abstract

THE α-β transformation, as observed by X-rays, has always held a position of central importance in any considerations on the molecular structure of keratin. It is therefore surprising that no quantitative investigation of the intensity variation of different reflexions comprising the X-ray diagram has been reported in the literature. It is generally accepted that the X-ray diagram of keratin changes little up to about 20 per cent extension (α-pattern), undergoes a rapid change between 30 and 50 per cent extension, and remains essentially unchanged during further extension (β-pattern)1,2. It is also claimed that the onset of the transformation always occurs at about 20 per cent extension irrespective of the medium in which the fibres are stretched1, and that the general character of the transformation is unaffected by relaxation effects and a wide variety of chemical treatments2. © 1957 Nature Publishing Group.