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PMID: 1059082 Published · ppublish English Journal Article Research Support, U.S. Gov't, Non-P.H.S.

Aspartic acid racemization in tooth enamel from living humans.

Proceedings of the National Academy of Sciences of the United States of America ·Vol. 72 ·No. 8 ·1975-08-00 ·Pages 2891-4

Helfman PM, Bada JL

Abstract

The aspartic acid in human tooth enamel shows increasing racemization with age. This increase is not seen in the metabolically active protein hemoglobin. The rate constant for the racemization reaction of aspartic acid in human tooth enamel was found to be 8.29 X 10(-4) yr-1. This rate constant suggests that in any protein with a long in vivo lifetime, D-aspartic acid will accumulate with age (about 8% of total aspartic acid in enamel will be the D-enantiomer after 60 years). Thus, racemization may play some role in the aging process affecting metabolically stable tissues in long-lived homeotherms. Aspartic acid racemization in toogh enamel also provides a biochronological tool for assessing the age of living mammals.

MeSH Terms
Adolescent Adult Aged Aging Aspartic Acid/metabolism Child Dental Enamel/growth & development,metabolism Humans Mathematics Middle Aged Stereoisomerism
Chemicals
Aspartic Acid
Authors & Affiliations
2 authors, click to expand affiliations / ORCID
Helfman P M
Bada J L
References (17)
17 references, click to expand
  1. Studies of metabolic turnover with tritium as a tracer. V. The predominantly non-dynamic state of body constituents in the rat.
    J Biol Chem. 1956 Dec;223(2):795-809 PMID: 13385227
  2. Metabolically inert proteins of the central and peripheral nervous system, muscle and tendon.
    Biochem J. 1961 Feb;78:272-82 PMID: 13720257
  3. On the origin of bile pigment in normal man.
    J Biol Chem. 1950 May;184(1):351-8 PMID: 15422003
  4. Racemization of amino acids in marine sediments.
    Science. 1971 Sep 3;173(4000):907-11 PMID: 17751312
  5. Caucasus and Altay longevity: a biological or social problem?
    Gerontologist. 1974 Oct;14(5 pt 1):381-7 PMID: 4470522
  6. Concordance of collagen-based radiocarbon and aspartic-acid racemization ages.
    Proc Natl Acad Sci U S A. 1974 Mar;71(3):914-7 PMID: 4522802
  7. Kinetics of racemization of amino acids as a function of pH.
    J Am Chem Soc. 1972 Feb 23;94(4):1371-3 PMID: 5060280
  8. Marine sediments: dating by the racemization of amino acids.
    Science. 1970 Nov 13;170(3959):730-2 PMID: 5479627
  9. Studies of the composition of teeth. III. The amino acid composition of human dentinal protein.
    J Dent Res. 1956 Apr;35(2):255-9 PMID: 13319550
  10. Determination of D- and L-amino acids by ion exchange chromatography as L-D and L-L dipeptides.
    J Biol Chem. 1968 Nov 10;243(21):5591-7 PMID: 5699053
  11. The existence of an embryonic crystalline protein.
    Ann Ocul (Paris). 1956 Oct;189(10):836-55 PMID: 13382027
  12. Possible relation between optical activity and aging.
    Adv Enzymol Relat Subj Biochem. 1958;20:1-29 PMID: 13605978
  13. Racemization reaction of aspartic Acid and its use in dating fossil bones.
    Proc Natl Acad Sci U S A. 1973 May;70(5):1331-4 PMID: 16592082
  14. Glacial-postglacial temperature difference deduced from aspartic Acid racemization in fossil bones.
    Science. 1973 Nov 2;182(4111):479-82 PMID: 17832466
  15. The limitation of human population: a natural history.
    Science. 1975 Feb 28;187(4178):713-21 PMID: 1090000
  16. Evolution and the distribution of glutaminyl and asparaginyl residues in proteins.
    Proc Natl Acad Sci U S A. 1974 Mar;71(3):885-8 PMID: 4522799
  17. New evidence for the antiquity of man in North America deduced from aspartic acid racemization.
    Science. 1974 May 17;184(4138):791-3 PMID: 4595240
Article Info
Journal
Proceedings of the National Academy of Sciences of the United States of America
Abbr.
Proc Natl Acad Sci U S A
ISSN
0027-8424
DOI
10.1073/pnas.72.8.2891
Published
1975-08-00
Pages
2891-4
Language
English
Region
United States
NLM ID
7505876
PMCID
PMC432884
Subset
IM
External Links
PubMed source DOI: 10.1073/pnas.72.8.2891 PMC Full Text View journal details
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