Amino acids in hair

Some hair-coloring products contain the water-soluble compound lead (II) acetate, Pb(CH3COO)2. When the coloring product is applied to the hair, a chemical reaction occurs between the Pb2+ ion and the sulfur atoms in cysteine and methionine incorporated in amino acids in hair proteins. The insoluble black product lead(II) sulfide forms. 

Zahn et al. [58, 59] have reported that thioglycolate can accelerate the rate of formation of thioether residues (lanthionyl) in wool fiber. Therefore, one might expect to find trace quantities of this amino acid in hair permanent-waved in an alkaline medium. Chao et al. [60] have demonstrated small quantities of lanthionine and carboxymethyl thiocysteine in hair reduced by thioglycolic acid. 

Tuccori S. Use of amino acids in hair treatment 2001. Patent US 20010051141 Al. 

Sulfur has a striking ability to catenate, or form chains of atoms. Oxygen s ability to form chains is very limited, with H2Oz, 03, and the anions 02,022-, and 03 the only examples. Sulfur s ability is much more pronounced. It appears, for instance, in the existence of S8 rings, their fragments, and the long strands of plastic sulfur that form when sulfur is heated to about 200°C and suddenly cooled. The — S—S— links that connect different parts of the chains of amino acids in proteins are another example of catenation. These disulfide links contribute to the shapes of proteins, including the keratin of our hair thus, sulfur helps to keep us alive and, perhaps, curly haired. 

Kerr and Godin (1959) showed similar end groups to be present in human hair and horsehair, and Hahnel (1959) found the same end groups in hair, callus, nails, and psoriasis scales. An unexplained finding in this latter work is that the total amount of N-terminal amino acids in psoriasis scales is at least ten times greater than for other keratins. Burley and de Kock... 

Blackburn and Lee (1954) using hydrazinolysis showed qualitatively that alanine, glycine, serine, and threonine were present as C-terminal amino acids in wool, and Kerr and Godin (1959) obtained similar results from human hair and horsehair. A more thorough study by Bradbury... 

Methylmercury is rapidly and nearly completely absorbed from the gastrointestinal tract 90-100% absorption is estimated. Methylmercury is somewhat lipophilic, allowing it to pass through lipid membranes of cells and facilitating its distribution to all tissues, and it binds readily to proteins. Methylmercury binds to amino acids in fish muscle tissue. The highest methylmercury levels in humans generally are found in the kidneys. Methylmercury in the body is considered to be relatively stable and is only slowly transformed to other forms of mercury. Methylmercury readily crosses the placental and blood/brain barriers. Its estimated half-life in the human body ranges from 44 to 80 days. Excretion of methylmercury is via the feces, urine, and breast milk. Methylmercury is also distributed to human hair and to the fur and feathers of wildlife measurement of mercury in hair and these other tissues has served as a useful biomonitor of contamination levels. 

Hair Complex 20/70n. [Henkel/Cospha] Placenta extract, B vitamins, and sulfur-containing amino acids in water-alcohol medium aq.-alcoholic lotions for regenerative hair care, oily scalps, dandruff. 

Active studies of the basic amino acids in the epidermis in the 1930 s sought to make a distinction between the hard keratin (eukeratin) of hair, horn, nails etc., and the soft keratin (pseudokeratin) of the epidermis, horse burrs, and whalebone (20). The results of independent workers like Block (19) and Eckstein (29) were in agreement in the case of pepsin- or trypsin-treated epidermis where the ratios of histidine lysine arginine residues were approximately 1 3 3. These results were in marked contrast to the earlier work of Wilkinson (57) who found a... 

Composition of the Proteins of Human Hair 69 Table 2-3. Amino acids in whole unaltered human hair (pmol/g of dry hair). 

Nineteen amino acids in human hair have been studied for possible modification during permanent waving (i.e., all the amino acids of Table 2-1 except tryptophan and citrulUne). Significant decreases in cystine (2 to 14%) and corresponding increases in cysteic acid [1,10] and cysteine [1] have been reported for human hair that has been treated either on the head by home... 

Bradbury et al. [16] have suggested that the cuticle of human hair contains more cystine, cysteic acid, proline, serine, threonine, isoleucine, methionine, leucine, tyrosine, phenylalanine, and arginine than does whole fiber. Data calculated from Bradbury s results and those of Robbins and Kelly [12] on whole human hair fibers are summarized in Table 2-7. Lustig and Kondritzer [18] have described comparative cuticle and cuticle-free hair analyses of certain amino acids in human hair, and their data are qualitatively similar to those of Bradbury. In addition, these authors suggest less tryptophan and histidine in cuticle than in whole fiber. 

Table 2-8. Amino acids in intercellular cement of hair and wool fiber [79, 80].

Kerr and Godin [90], using the dinitrophenylation method of Sanger [91], have identified valine, threonine, glycine, alanine, serine, glutamic acid, and aspartic acid as N-terminal amino acids in human hair. Quantitative data... 

Table 2-9. N-terminal amino acids in human hair (relative ratios).

I I ur bodies are built of proteims—from micro.< copic cell consriments,. such as V/ enzymes and organelles, to. such macroscopic structures as bones, hair, skin, and teeth. The number of different ways amino acids can link together to make proteins is fanta.stic. Yet, somehow our bodies are able to a.s.semble amino acids in just the right order to build proteins that have highly functional structures. 

Table 3. Peak list comparison. List of masses showing a difference of "n x 14.0157 Da" with less than 15 PPM error between MALDl-MS spectra from untreated and esterified samples. Init. mass list of masses in the native sample spectrum that matched with peak masses of the esterified sample. Mass ester masses in the esterified sample spectrum ester potential number of ester groups on the peptide chain (n from 1 to 6) D E potential number ofD and E amino acids in the peptide sequence (n-1 due to the C-termirutl esterification) Protein source the protein to which the peptide corresponds (Protein named 095678 and K2C1 HUMAN are two cytoskeletal keratin type II from hair) Bold letters in sequence column represent potential position of the esterification site on the sequence from D and E amino acids and letters in italics represent potential esterification at the C-terminal amino acid. MSO methionine sulfoxide...

Definition Condensation prod, of propionic acid chloride with collagen amino acids Uses Hair conditioner, detangling agent in cosmetics... 

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