Wool from Animal Sources

Abstract

Introduction Historical Outline Cell Biology The Wool Follicle Expression of Keratin and KAP Genes in Wool Follicle Differentiations Occurrence Sheep Rearing and Breeding Places of Origin and Types of Raw Wool Wool Fiber Geometry Morphology Structural Biology Bonding and Interactions in Wool Fibers α‐ and β‐Keratin Structures in the Cortical Microfibrils Chemical Composition of Wool and its Morphological Components Proteins Free Internal Lipids Covalently Bound Lipids Chemical Analysis Physical and Mechanical Properties Water Absorption Mechanical Properties Glass Transition Thermal Denaturation Wool as a Polyampholyte Chemical Reactivity Dry Heat Moist Heat Acid Degradation Degradation by Alkali Reducing Agents Photodegradation Clothing Physiology Biochemistry Isolation of Wool Proteins Amino Acid Sequences of Wool Proteins Morphological Location of Wool Proteins Biodegradation Enzymatic Degradation Molecular Genetics Production Wool Collection Raw Wool Scouring Mechanical Processing Chemical Processing World Market and Prices Outlook Acknowledgments

Wet degradation of keratin proteins: linking amino acid, elemental and isotopic composition

“…AA content of control wool samples determined by RP-HPLC closely resembled previous determinations of AA relative concentration in wool [41,42] (calculations for recovered AAs only; all differences less than 1.5%). The median [AA]% content of un-degraded wool samples was very similar to the theoretical [AA]% contents of IFP proteins, which make up the bulk of the wool fibre ( Supplementary Table S6, wileyonlinelibrary.com/journal/rcm Supporting Information).…”

Hair—the most sophisticated biological composite material

“…The data given in Table 2 were obtained by combining data from acidic and from enzymatic hydrolyses of wool, as an example of an a-keratin fibre. 31 The amino acids are classified into five groups: ''acidic'' amino acids, ''basic'' amino acids, amino acids with hydroxyl groups, sulfur-containing amino acids, and amino acids with no reactive groups in the side chain. The total amount of amino acids with reactive side groups is 4940 mmol g 21 , and of amino acids without reactive side groups 3450 mmol g 21 .…”

“…13. 31 The letters may be replaced by any amino acid residue from Table 2, with the only requirement that amino acids a and d are hydrophobic ones. 31 In addition to the organic constituents, trace elements were detected.…”

“…31 The letters may be replaced by any amino acid residue from Table 2, with the only requirement that amino acids a and d are hydrophobic ones. 31 In addition to the organic constituents, trace elements were detected. The ash content of a hair ranges from 0.3 to 1% and the most frequent elements met are Ca, Cd, Zn, Cr, Cu, Fe, As, Si, Pb and Hg.…”

A novel metalloprotease from Bacillus cereus for protein fibre processing

“…The high concentration of cystine crosslinkages on wool surface is a special feature of keratin fibres. Reaction of cystine crosslinkages with oxidants and reductants are of major importance, being an integral part of the wool chemistry involved in isolating wool proteins [1]. This component of the keratin structure contributes largely to the physical and mechanical properties of the wool fibre.…”