X-ray Evidence of Regularly Distributed Lysine in α Keratin

The viscoelastic properties of wool and the influence of some specific plasticizers

“…The birefringence of a wool fiber decreases compared to the value in water when the fiber is immersed in methanol and even more so when immersed in ethanol, suggesting an influence of the alcohols, increasing with their K 160 hydrophobicity, on the crystalline morphological components of the wool fiber. In agreement with this observation Feughelman and Snaith [8] found, though not undisputed by others [10], an increased swelling of the crystalline a-keratin in the presence of alcohols, which they partly attributed to the interaction of nonpolar groups in the crystalline regions of the a-keratin and the non-polar groups of the alcohols. From X-ray data Fraser et al [11] deduced a coiled coil rope structure for the aggregation of the or-helical units and showed that clusters of uncharged residues form the interrope contacts, emphazising the potential importance of the interactions of the non-polar groups for the stability of the a-helical aggregates.…”

R�ntgenographische Untersuchungen des Mikrofibrillen-Matrix-Komplexes von?-Keratinen mit unterschiedlichem Matrixgehalt

“…Um weitere Informationen fiber die Wechselwirkung von TFE und HFIP mit Faserkeratinen zu erhalten, haben wir nun auch das Kontraktionsverhalten von verschiedenen a-Keratinen in diesen L6sungs-mitteln untersucht, da Heidemann und Halboth [25] gefunden hatten, dal3 der 66/k Netzebenenabstand (die sog…”

“…Bei einem Quellen der Protofibrillen muff aber zwangsl~iufig eine Kontraktion der meridionalen Netzebenenabst~nde -wie oben beschrieben -auftreten. Da nach der Quellung von a-Keratinen in Wasser keine Kontraktionen der meridionalen Netzebenenabst~inde beobachtet werden [8,36] …”