KERATIN

kĕrˈətĭn, any one of a class of fibrous protein molecules that serve as structural units for various living tissues. The keratins are the major protein components of hair, wool, nails, horn, hoofs, and the quills of feathers. These proteins generally contain large quantities of the sulfur-containing amino acids, particulary cysteine. The helical keratin molecules twist around each other to form elongated strands called intermediate filaments. The formation of a covalent chemical bond called a disulfide bridge between the sulfer atoms on two cysteins on separate polypeptide chains of keratin allows for the cross-linkage of these chains and results in a fairly rigid aggregate. This phenomenon is seen to be consistent with the physiological role of the keratins, which provide a tough, fibrous matrix for the tissues in which they are found. Human hair is approximately 14% cystine (cysteins cross-linked by disulfide bridges).

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The Columbia Encyclopedia, Sixth Edition Copyright© 2004, Columbia University Press. Licensed from Lernout & Hauspie Speech Products N.V. All rights reserved.

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Questia Books and Articles on: Keratin
We found: 464 results
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149  

 

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57  

 

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books on: Keratin  - 149 results

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1.
Unity and Diversity in Biochemistry: An Introduction to Chemical Biology
Book by Marcel Florkin, T. Wood; Pergamon Press, 1960
Subjects: Biochemistry
...muscles, fibrin present in blood clots, keratin and epidermin of vertebrate skin, the...into two groups: the k-m-e-f group keratin-myosin-epidermin-fibrin and the...spectra show that stretched fibres of keratin ss-keratin are formed by the repetition...
2.
The Elements of Archaeological Conservation
Book by J. M. Cronyn; Routledge, 1990
Subjects: Antiquities--Collection And Preservation, Archaeology--Methodology
...hair, wool, claws, hooves, and whalebone (baleen), these materials are all based on the protein keratin. 6.5.1.1 Keratin Keratin is composed of a number of different amino acids (section 6.1.1.2), some of which contain sulphur...
3.
Encyclopedia of Life Sciences - Vol. 7
Book by Anne O'Daly; Marshall Cavendish, 2004
Subjects: Biology--Encyclopedias, Life Sciences--Encyclopedias
HORNS Horns, made from bone and keratin, are used in defense, in sexual combat...I :i 0 Keratin, an important component that surrounds...made of a bonv core enclosed in an Touter keratin (fil>rous protein) sheath, are pre...
4.
Bad Medicine: Misconceptions and Misuses Revealed, from Distance Healing to Vitamin O
Book by Christopher Wanjek; Wiley, 2003
Subjects: Medical Misconceptions
...Cells in the follicle produce the protein keratin, the main ingredient in hair. Follicle...gives skin its color. Melanin colors the keratin. Folks who are flush with melanin have...strand. Hair is a lifeless strand of keratin that cannot transport nutrients or information...
5.
The Chemistry and Physiology of Growth
Book by J. H. Northrop, E. S. G. Barron, F. O. Schmitt, K. V. Thimann, J. S. Nicholas, Karl Folkers, C. P. Rhoads, C. B. Van Niel, C. N. H. Long, Arthur K. Parpart; Princeton Univ. Press, 1949
Subjects: Biochemistry, Growth
...particular protein, such as keratin, in the various phyla and classes...have begun such a study of the keratins. "Feather" keratin, which is of the beta variety...birds; in other vertebrates the keratin is of the alpha type. In reptiles...
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journal articles on: Keratin  - 57 results

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1.
Association of Chromosomal Alterations with Arsenite-Induced Tumorigenicity of Human HaCaT Keratinocytes in Nude Mice
Journal article by Chia-Wen Chien, Ming-Chang Chiang, I-Ching Ho, Te-Chang Lee; Environmental Health Perspectives, Vol. 112, 2004
Subjects: Cancer treatment, Cancer--Care and treatment, Tumors
...expressed higher levels of keratin 6, a proliferation...whereas the expression of keratins 5, 8, and 10 was significantly...pattern of expression of keratins, except that the levels of keratins 7 and 17 were unchanged and keratin 6 levels were significantly...
2.
Recycling Poultry Feathers: More Bang for the Cluck
Journal article by Victoria Mcgovern; Environmental Health Perspectives, Vol. 108, 2000
...processed quickly and very inexpensively. The Keratin Connection Feathers are made of keratin, the same tough, tightly wound protein fiber...analytical chemistry, began working with feather keratin because he was studying another fibrous protein...
3.
Pitfalls of Mapping a Large Turkish Consanguineous Family with Vertical Monilethrix Inheritance
Journal article by F. Celep, A. Uzumcu, F. M. Sonmez, O. Uyguner, Y. Isik Balci, S. Bahadir, A. Karaguzel; Genetic Counseling, Vol. 20, 2009
...genes coding for keratin intermediate...mutated epithelial keratins holds also true...interfil.org). Keratin protein family...of epithelial keratins expressed mainly...acidic hair keratins could be responsible, since keratin filaments are...
4.
Chicken Electronics: A Technology Plucked from Waste
Journal article by Lance Frazer; Environmental Health Perspectives, Vol. 112, 2004
Subjects: Electronics industry, Emissions (Pollution), Poultry industry
...ideal." Feathers are made of the protein keratin, which in fiber form is both light and...pressed into thin mats. Wool coated the keratin fiber mats with two different commercial...The best end product so far, using 30% keratin by weight, has a lower dielectric constant...
5.
The Need to Decide If All Estrogens Are Intrinsically Similar
Journal article by Jonathan G. Moggs, John Ashby, Helen Tinwell, Fei Ling Lim, David J. Moore, Ian Kimber, George Orphanides; Environmental Health Perspectives, Vol. 112, 2004
...family U74079 1.8 + or - 0.01 9a3r1 Keratin complex 2-8 X15662 2.6 + or - 0...11.9 + or - 1.6 adhesion molecule 2 Keratin complex 1-19 M36120 4.4 + or - 0...AI197481 3.5 + or - 1.0 protein 1 Keratin complex 1-19 AU040563 4.5 + or - 1...
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magazine articles on: Keratin  - 53 results

       More magazine Results: 1-10 11-20 21-30 31-40 41-50 >>  
 
1.
The Allergy Gene
Magazine article by W. H. Irwin McLean; The Scientist, Vol. 24, December 2010
Subjects: Asthma, Eczema, Immune system, Medical research, Molecular weight, Mutation, Research & development--R&D, Skin diseases
...genetic disorders of keratin genes. Keratins form the filamentous...strength from this tough keratin cytoskeleton in their cytoplasm, and defects in keratin genes make the skin...case of the epidermal keratins, this manifests as...
2.
Tough as Nails
Magazine article by Carl Zimmer; Natural History, Vol. 108, September 1999
Subjects: Feet, Horses, Injuries, Research
...wrapping around the foot. Its made of keratin, the same kind of protein found in human...toenails, cells manufacture filaments of keratin that are braided together like the strands...by a gluelike substance, and all the keratin in the sheets also runs in the same direction...
3.
Making the Most of It: How Nature Turns Weakness into Strength
Magazine article by Aimee Cunningham; Science News, Vol. 169, March 25, 2006
Subjects: Environmental engineering--Forecasts and trends, Environmental engineering--Research, Scientists--Research
...millimeter-thicklayer of the protein keratin, the same material found in human fingernails. As tough as keratin is, a uniform layer the size of a toucan...beaks outer shell is made of hexagonal keratin tiles--each about 50 microm in diameter...
4.
FYI
Magazine article by Bjorn Carey, Rosa Pastore, Victor Zapana; Popular Science, Vol. 277, October 2010
Subjects: Brain damage, Hair, Medical research
...made of a densely packed protein called keratin, which is chemically inactive in hair...manufacturers use L-cysteine, an amino acid in keratin, to stabilize dough and perk up the taste...acid to extract the L-cysteine from the keratin. Yummy hair derivative aside, theres...
5.
A Sickening Situation
Magazine article by Yvonne Baskin; Natural History, Vol. 109, April 2000
Subjects: Animal populations, Endangered & extinct species, Pathogens
...tadpoles. This fungus feeds on the protein keratin (the main constituent of hair, nails...mouthparts of tadpoles also consist of keratin, enabling the chytrid to subsist in larval...start to metamorphose and develop the keratin-rich skin of the adult stage. At this...
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newspaper articles on: Keratin  - 196 results

       More newspaper Results: 1-10 11-20 21-30 31-40 41-50 >>  
 
1.
This Week We Roadtest a Brazilian Keratin Hair Treatment. BEAUTY BIBLE
Newspaper article; The Journal (Newcastle, England), August 22, 2009
Subjects: Keratin
This Week We Roadtest a Brazilian Keratin Hair Treatment. BEAUTY BIBLE. Byline: Liz...uncontrollable mane then this treatment by Global Keratin could be a godsend. Developed in Brazil, the Keratin hair treatment is designed to remove frizz...
2.
THERAPY OF THE WEEK; Brazilian Keratin Treatment
Newspaper article; The Daily Mail (London, England), June 15, 2009
Subjects: Keratin
THERAPY OF THE WEEK; Brazilian Keratin Treatment. Byline: RACHAEL LLOYD FOR...bushy hair -- the fantastic Brazilian Keratin Treatment (or BKT). The product contains...embalming, but here is enriched with keratin, a natural protein, to form a mild chemical...
3.
Hair Clippings Could Bring Damaged Nerves Back to Life; Barber Shop Cure: Hair Clippings
Newspaper article; The Daily Mail (London, England), January 15, 2008
Subjects: Keratin
...University in North Carolina tested the keratin gelon animals and found it speeded up...to accomplish this withgels made from keratin is pretty remarkable. This is believed to be the firsttime keratin gel has been used to heal damaged nerves...
4.
Hair
Newspaper article; The Washington Times, October 8, 2008
Subjects: Keratin, Pharmaceutical industry, Roche Holding Ltd.
...treatment at Roche Salon in Georgetown is the Keratin Complex Hair Therapy Smoothing System...heartbeat and looks very smooth. The keratin treatment is part of the evolution of...three times a year. Then came Brazilian keratin treatments (BKT), which were a little...
5.
Treatment of the Week
Newspaper article; The Daily Mail (London, England), December 27, 2010
Subjects: Keratin
...can tell you. Childrens hair is rich in keratin, a substance that makes it silky and...hair. Ive extolled the virtues of my keratin treatment before. I t s a great, intensive...required. But, as the hair grows, the keratin effect begins to fade. When that happens...
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encyclopedia articles on: Keratin  - 9 results

       More encyclopedia Results: 1-9 >>  
 
1.
Keratin
Encyclopedia article; The Columbia Encyclopedia, Sixth Edition, 2009
KERATIN ker tin, any one...living tissues. The keratins are the major protein...cysteine . The helical keratin molecules twist around...polypeptide chains of keratin allows for the cross...physiological role of the keratins, which provide a...
2.
Protein
Encyclopedia article; The Columbia Encyclopedia, Sixth Edition, 2009
...catalyzing the thousands of chemical reactions of the living cell; keratin , elastin, and collagen , which are important types of structural...or conformation. Fibrous proteins, such as collagen and keratin, consist of polypeptide chains arranged in roughly parallel...
3.
Prickly Heat
Encyclopedia article; The Columbia Encyclopedia, Sixth Edition, 2009
PRICKLY HEAT (miliaria), inflammatory skin eruption due to obstruction of the sweat glands by keratin, the substance that forms the horny cells of the epidermis. It consists of blisterlike elevations with burning and itching...
4.
Horn , in Zoology
Encyclopedia article; The Columbia Encyclopedia, Sixth Edition, 2009
...related animals the horns are permanent and unbranched and are usually present in both sexes. They are composed of a sheath of keratin a tough fibrous material derived from epithelial tissue overlying a bony core projecting from the skull. In the deer family...
5.
Blackhead
Encyclopedia article; The Columbia Encyclopedia, Sixth Edition, 2009
BLACKHEAD yellowish or blackish plug of material accumulated in the duct of a sebaceous gland. The material consists of keratin (horny cells of the epidermis) and modified sebum (oily secretions of the sebaceous gland). Blackheads are the primary...
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