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Amino acid dating

January 20, 2023

Amino acid dating is a dating technique used to estimate the age of a specimen in paleobiology, molecular paleontology, archaeology, forensic science, taphonomy, sedimentary geology and other fields. This technique relates changes in amino acid molecules to the time elapsed since they were formed.[1][2][3][4][5]

All biological tissues contain amino acids. All amino acids except glycine (the simplest one) are optically active, having a stereocenter at their α-C atom. This means that the amino acid can have two different configurations, "D" or "L" which are mirror images of each other. With a few important exceptions, living organisms keep all their amino acids in the "L" configuration. When an organism dies, control over the configuration of the amino acids ceases, and the ratio of D to L moves from a value near 0 towards an equilibrium value near 1, a process called racemization. Thus, measuring the ratio of D to L in a sample enables one to estimate how long ago the specimen died.[6]

Factors affecting racemization

The rate at which racemization proceeds depends on the type of amino acid and on the average temperature, humidity, acidity (pH), and other characteristics of the enclosing matrix. Also, D/L concentration thresholds appear to occur as sudden decreases in the rate of racemization. These effects restrict amino acid chronologies to materials with known environmental histories and/or relative intercomparisons with other dating methods.

Temperature and humidity histories of microenvironments are being produced at ever increasing rates as technologies advance and technologists accumulate data. These are important for amino acid dating because racemization occurs much faster in warm, wet conditions compared to cold, dry conditions. Temperate to cold region studies are much more common than tropical studies, and the steady cold of the ocean floor or the dry interior of bones and shells have contributed most to the accumulation of racemization dating data. As a rule of thumb, sites with a mean annual temperature of 30 °C have a maximum range of 200 ka and resolution of about 10 ka; sites at 10 °C have a maximum age range of ~2 Ma, and resolution generally about 20% of the age; at -10 °C the reaction has a maximum age of ~10 Ma, and a correspondingly coarser resolution.[6]

Strong acidity and mild to strong alkalinity induce greatly increased racemization rates. Generally, they are not assumed to have a great impact in the natural environment, though tephrochronological data may shed new light on this variable.

The enclosing matrix is probably the most difficult variable in amino acid dating. This includes racemization rate variation among species and organs, and is affected by the depth of decomposition, porosity, and catalytic effects of local metals and minerals.

Amino acids used

Conventional racemization analysis tends to report a D-alloisoleucine / L-isoleucine (A/I or D/L ratio). This amino acid ratio has the advantages of being relatively easy to measure and being chronologically useful through the Quaternary.[7]

Reversed phase HPLC techniques can measure up to 9 amino acids useful in geochronology over different time scales on a single chromatogram (aspartic acid, glutamic acid, serine, alanine, arginine, tyrosine, valine, phenylalanine, leucine).[8][9][10]

In recent years there have been successful efforts to examine intra-crystalline amino acids separately as they have been shown to improve results in some cases.[11]

Applications

Data from the geochronological analysis of amino acid racemization has been building for thirty-five years. Archeology,[4] stratigraphy, oceanography, paleogeography, paleobiology, and paleoclimatology have been particularly affected. Their applications include dating correlation, relative dating, sedimentation rate analysis, sediment transport studies,[12] conservation paleobiology,[13] taphonomy and time-averaging,[14][15][16] sea level determinations, and thermal history reconstructions.[17][18][19][20]

Paleobiology and archaeology have also been strongly affected. Bone, shell, and sediment studies have contributed much to the paleontological record, including that relating to hominoids. Verification of radiocarbon and other dating techniques by amino acid racemization and vice versa has occurred.[21] The 'filling in' of large probability ranges, such as with radiocarbon reservoir effects, has sometimes been possible. Paleopathology and dietary selection, paleozoogeography and indigeneity, taxonomy and taphonomy, and DNA viability studies abound. The differentiation of cooked from uncooked bone, shell, and residue is sometimes possible. Human cultural changes and their effects on local ecologies have been assessed using this technique.

The slight reduction in this[clarification needed] repair capability during aging is important to studies of longevity and old age tissue breakdown disorders, and allows the determination of age of living animals.

Amino acid racemization also has a role in tissue and protein degradation studies, particularly useful in developing museum preservation methods. These have produced models of protein adhesive and other biopolymer deteriorations and the concurrent pore system development.

Forensic science can use this technique to estimate the age of a cadaver[22] or an objet d'art to determine authenticity.

Procedure

Amino acid racemization analysis consists of sample preparation, isolation of the amino acid wanted, and measure of its D:L ratio. Sample preparation entails the identification, raw extraction, and separation of proteins into their constituent amino acids, typically by grinding followed by acid hydrolysis. The amino acid derivative hydrolysis product can be combined with a chiral specific fluorescent, separated by chromatography or electrophoresis, and the particular amino acid D:L ratio determined by fluorescence. Alternatively, the particular amino acid can be separated by chromatography or electrophoresis, combined with a metal cation, and the D:L ratio determined by mass spectrometry. Chromatographic and electrophoretic separation of proteins and amino acids is dependent upon molecular size, which generally corresponds to molecular weight, and to a lesser extent upon shape and charge.

References

  1. ^ Bada JL (1985). "Amino Acid Racemization Dating of Fossil Bones". Annual Review of Earth and Planetary Sciences. 13: 241–268. Bibcode:1985AREPS..13..241B. doi:10.1146/annurev.ea.13.050185.001325.
  2. ^ Canoira L, García-Martínez MJ, Llamas JF, Ortíz JE, Torres TD (2003). "Kinetics of amino acid racemization (epimerization) in the dentine of fossil and modern bear teeth". International Journal of Chemical Kinetics. 35 (11): 576–591. doi:10.1002/kin.10153.
  3. ^ Bada JL, McDonald GD (1995). "Amino acid racemization on Mars: implications for the preservation of biomolecules from an extinct martian biota". Icarus. 114 (1): 139–143. Bibcode:1995Icar..114..139B. doi:10.1006/icar.1995.1049. PMID 11539479.
  4. ^ a b Johnson BJ, Miller GH (1997). "Archaeological Applications of Amino Acid Racemization". Archaeometry. 39 (2): 265–287. doi:10.1111/j.1475-4754.1997.tb00806.x.
  5. ^ Scarponi D, Kaufman D, Bright J, Kowalewski M (October 2008). . Geological Society of America Abstracts with Programs. 40 (6): 502. Archived from the original on 2015-01-22. The results provide a compelling case for applicability of amino acid racemization methods as a tool for evaluating changes in depositional dynamics, sedimentation rates, time-averaging, temporal resolution of the fossil record, and taphonomic overprints across sequence stratigraphic cycles.
  6. ^ a b . Amino acid geochronology laboratory. Northern Arizona University. Archived from the original on 2 October 2016.
  7. ^ "NEaar: North East Amino Acid Racemization". University of York.
  8. ^ Kaufman DS, Manley WG (1998). "A new procedure for determining dl amino acid ratios in fossils using reverse phase liquid chromatography". Quaternary Science Reviews. 17 (11): 987–1000. Bibcode:1998QSRv...17..987K. doi:10.1016/S0277-3791(97)00086-3.
  9. ^ Kaufman DS (2000). Perspectives in Amino Acid and Protein Geochemistry. New York: Oxford University Press. pp. 145–160.
  10. ^ "Method". Amino Acid Geochronology Laboratory. Northern Arizona University.
  11. ^ Penkman KE, Kaufman DS, Maddy D, Collins MJ (February 2008). "Closed-system behaviour of the intra-crystalline fraction of amino acids in mollusc shells". Quaternary Geochronology. 3 (1–2): 2–25. doi:10.1016/j.quageo.2007.07.001. PMC 2727006. PMID 19684879.
  12. ^ Kosnik MA, et al. (2007). "Sediment mixing and stratigraphic disorder revealed by the age-structure of Tellina shells in Great Barrier Reef sediment". Geology. 35 (9): 811–814. Bibcode:2007Geo....35..811K. doi:10.1130/G23722A.1.
  13. ^ Kowalewski M, Serrano GE, Flessa KW, Goodfriend GA (2000). "Dead delta's former productivity: Two trillion shells at the mouth of the Colorado River". Geology. 28 (12): 1059–1062. Bibcode:2000Geo....28.1059K. doi:10.1130/0091-7613(2000)28<1059:DDFPTT>2.0.CO;2.
  14. ^ Carroll M, Kowalewski M, Simões MG, Goodfriend GA (2003). "Quantitative estimates of time-averaging in terebratulid brachiopod shell accumulations from a modern tropical shelf". Paleobiology. 29 (3): 381–402. doi:10.1666/0094-8373(2003)029<0381:QEOTIT>2.0.CO;2. S2CID 131237779.
  15. ^ Kidwell SM, Best MM, Kaufman DS (2005). "Taphonomic trade-offs in tropical marine death assemblages: Differential time averaging, shell loss, and probable bias in siliciclastic vs. Carbonate facies". Geology. 33 (9): 729–732. Bibcode:2005Geo....33..729K. doi:10.1130/G21607.1.
  16. ^ Kosnik MA, Hua Q, Kaufman DS, Wüst RA (2009). "Taphonomic bias and time-averaging in tropical molluscan death assemblages: Differential shell half-lives in Great Barrier Reef sediment". Paleobiology. 35 (4): 565–586. doi:10.1666/0094-8373-35.4.565. S2CID 5839861.
  17. ^ McCoy WD (1987). "The precision of amino acid geochronology and paleothermometry". Quaternary Science Reviews. 6 (1): 43–54. Bibcode:1987QSRv....6...43M. doi:10.1016/0277-3791(87)90016-3.
  18. ^ Oches EA, McCoy WD, Clark PU (1996). "Amino acid estimates of latitudinal temperature gradients and geochronology of loess deposition during the last glaciation, Mississippi Valley, United States". Geological Society of America Bulletin. 108 (7): 892–903. Bibcode:1996GSAB..108..892O. doi:10.1130/0016-7606(1996)108<0892:AAEOLT>2.3.CO;2.
  19. ^ Miller GH, Magee JW, Jull AJ (1997). "Low-latitude glacial cooling in the Southern Hemisphere from amino-acid racemization in emu eggshells". Nature. 385 (6613): 241–244. Bibcode:1997Natur.385..241M. doi:10.1038/385241a0. S2CID 4312380.
  20. ^ Kaufman DS (2003). "Amino acid paleothermometry of Quaternary ostracodes from the Bonneville Basin, Utah". Quaternary Science Reviews. 22 (8–9): 899–914. Bibcode:2003QSRv...22..899K. doi:10.1016/S0277-3791(03)00006-4.
  21. ^ McMenamin MA, Blunt DJ, Kvenvolden KA, Miller SE, Marcus LF, Pardi RR (1982). "Amino acid geochemistry of fossil bones from the Rancho La Brea Asphalt Deposit, California". Quaternary Research. 18 (2): 174–183. Bibcode:1982QuRes..18..174M. doi:10.1016/0033-5894(82)90068-0.
  22. ^ Ogino T, Ogino H (October 1988). "Application to forensic odontology of aspartic acid racemization in unerupted and supernumerary teeth". Journal of Dental Research. 67 (10): 1319–1322. doi:10.1177/00220345880670101501. PMID 3170888. S2CID 8664035.

External links

 
The Wikibook Historical Geology has a page on the topic of: Amino acid dating

Active laboratories

  • Northern Arizona University Amino Acid Geochronology Laboratory 2017-03-31 at the Wayback Machine
  • University of Massachusetts Amino Acid Geochronology Laboratory
  • The University of Colorado Amino Acid Geochronology Lab
  • University of Delaware Research Group
  • University of York BioArCh

January 20, 2023
amino, acid, dating, dating, technique, used, estimate, specimen, paleobiology, molecular, paleontology, archaeology, forensic, science, taphonomy, sedimentary, geology, other, fields, this, technique, relates, changes, amino, acid, molecules, time, elapsed, s. Amino acid dating is a dating technique used to estimate the age of a specimen in paleobiology molecular paleontology archaeology forensic science taphonomy sedimentary geology and other fields This technique relates changes in amino acid molecules to the time elapsed since they were formed 1 2 3 4 5 All biological tissues contain amino acids All amino acids except glycine the simplest one are optically active having a stereocenter at their a C atom This means that the amino acid can have two different configurations D or L which are mirror images of each other With a few important exceptions living organisms keep all their amino acids in the L configuration When an organism dies control over the configuration of the amino acids ceases and the ratio of D to L moves from a value near 0 towards an equilibrium value near 1 a process called racemization Thus measuring the ratio of D to L in a sample enables one to estimate how long ago the specimen died 6 Contents 1 Factors affecting racemization 2 Amino acids used 3 Applications 4 Procedure 5 References 6 External links 6 1 Active laboratoriesFactors affecting racemization EditThe rate at which racemization proceeds depends on the type of amino acid and on the average temperature humidity acidity pH and other characteristics of the enclosing matrix Also D L concentration thresholds appear to occur as sudden decreases in the rate of racemization These effects restrict amino acid chronologies to materials with known environmental histories and or relative intercomparisons with other dating methods Temperature and humidity histories of microenvironments are being produced at ever increasing rates as technologies advance and technologists accumulate data These are important for amino acid dating because racemization occurs much faster in warm wet conditions compared to cold dry conditions Temperate to cold region studies are much more common than tropical studies and the steady cold of the ocean floor or the dry interior of bones and shells have contributed most to the accumulation of racemization dating data As a rule of thumb sites with a mean annual temperature of 30 C have a maximum range of 200 ka and resolution of about 10 ka sites at 10 C have a maximum age range of 2 Ma and resolution generally about 20 of the age at 10 C the reaction has a maximum age of 10 Ma and a correspondingly coarser resolution 6 Strong acidity and mild to strong alkalinity induce greatly increased racemization rates Generally they are not assumed to have a great impact in the natural environment though tephrochronological data may shed new light on this variable The enclosing matrix is probably the most difficult variable in amino acid dating This includes racemization rate variation among species and organs and is affected by the depth of decomposition porosity and catalytic effects of local metals and minerals Amino acids used EditConventional racemization analysis tends to report a D alloisoleucine L isoleucine A I or D L ratio This amino acid ratio has the advantages of being relatively easy to measure and being chronologically useful through the Quaternary 7 Reversed phase HPLC techniques can measure up to 9 amino acids useful in geochronology over different time scales on a single chromatogram aspartic acid glutamic acid serine alanine arginine tyrosine valine phenylalanine leucine 8 9 10 In recent years there have been successful efforts to examine intra crystalline amino acids separately as they have been shown to improve results in some cases 11 Applications EditData from the geochronological analysis of amino acid racemization has been building for thirty five years Archeology 4 stratigraphy oceanography paleogeography paleobiology and paleoclimatology have been particularly affected Their applications include dating correlation relative dating sedimentation rate analysis sediment transport studies 12 conservation paleobiology 13 taphonomy and time averaging 14 15 16 sea level determinations and thermal history reconstructions 17 18 19 20 Paleobiology and archaeology have also been strongly affected Bone shell and sediment studies have contributed much to the paleontological record including that relating to hominoids Verification of radiocarbon and other dating techniques by amino acid racemization and vice versa has occurred 21 The filling in of large probability ranges such as with radiocarbon reservoir effects has sometimes been possible Paleopathology and dietary selection paleozoogeography and indigeneity taxonomy and taphonomy and DNA viability studies abound The differentiation of cooked from uncooked bone shell and residue is sometimes possible Human cultural changes and their effects on local ecologies have been assessed using this technique The slight reduction in this clarification needed repair capability during aging is important to studies of longevity and old age tissue breakdown disorders and allows the determination of age of living animals Amino acid racemization also has a role in tissue and protein degradation studies particularly useful in developing museum preservation methods These have produced models of protein adhesive and other biopolymer deteriorations and the concurrent pore system development Forensic science can use this technique to estimate the age of a cadaver 22 or an objet d art to determine authenticity Procedure EditAmino acid racemization analysis consists of sample preparation isolation of the amino acid wanted and measure of its D L ratio Sample preparation entails the identification raw extraction and separation of proteins into their constituent amino acids typically by grinding followed by acid hydrolysis The amino acid derivative hydrolysis product can be combined with a chiral specific fluorescent separated by chromatography or electrophoresis and the particular amino acid D L ratio determined by fluorescence Alternatively the particular amino acid can be separated by chromatography or electrophoresis combined with a metal cation and the D L ratio determined by mass spectrometry Chromatographic and electrophoretic separation of proteins and amino acids is dependent upon molecular size which generally corresponds to molecular weight and to a lesser extent upon shape and charge References Edit Bada JL 1985 Amino Acid Racemization Dating of Fossil Bones Annual Review of Earth and Planetary Sciences 13 241 268 Bibcode 1985AREPS 13 241B doi 10 1146 annurev ea 13 050185 001325 Canoira L Garcia Martinez MJ Llamas JF Ortiz JE Torres TD 2003 Kinetics of amino acid racemization epimerization in the dentine of fossil and modern bear teeth International Journal of Chemical Kinetics 35 11 576 591 doi 10 1002 kin 10153 Bada JL McDonald GD 1995 Amino acid racemization on Mars implications for the preservation of biomolecules from an extinct martian biota Icarus 114 1 139 143 Bibcode 1995Icar 114 139B doi 10 1006 icar 1995 1049 PMID 11539479 a b Johnson BJ Miller GH 1997 Archaeological Applications of Amino Acid Racemization Archaeometry 39 2 265 287 doi 10 1111 j 1475 4754 1997 tb00806 x Scarponi D Kaufman D Bright J Kowalewski M October 2008 Quantifying time averaging in 4th order depositional sequences radiocarbon calibrated amino acid racemization dating of Late Quaternary mollusk shells from Po Plain Italy Geological Society of America Abstracts with Programs 40 6 502 Archived from the original on 2015 01 22 The results provide a compelling case for applicability of amino acid racemization methods as a tool for evaluating changes in depositional dynamics sedimentation rates time averaging temporal resolution of the fossil record and taphonomic overprints across sequence stratigraphic cycles a b Method Amino acid geochronology laboratory Northern Arizona University Archived from the original on 2 October 2016 NEaar North East Amino Acid Racemization University of York Kaufman DS Manley WG 1998 A new procedure for determining dl amino acid ratios in fossils using reverse phase liquid chromatography Quaternary Science Reviews 17 11 987 1000 Bibcode 1998QSRv 17 987K doi 10 1016 S0277 3791 97 00086 3 Kaufman DS 2000 Perspectives in Amino Acid and Protein Geochemistry New York Oxford University Press pp 145 160 Method Amino Acid Geochronology Laboratory Northern Arizona University Penkman KE Kaufman DS Maddy D Collins MJ February 2008 Closed system behaviour of the intra crystalline fraction of amino acids in mollusc shells Quaternary Geochronology 3 1 2 2 25 doi 10 1016 j quageo 2007 07 001 PMC 2727006 PMID 19684879 Kosnik MA et al 2007 Sediment mixing and stratigraphic disorder revealed by the age structure of Tellina shells in Great Barrier Reef sediment Geology 35 9 811 814 Bibcode 2007Geo 35 811K doi 10 1130 G23722A 1 Kowalewski M Serrano GE Flessa KW Goodfriend GA 2000 Dead delta s former productivity Two trillion shells at the mouth of the Colorado River Geology 28 12 1059 1062 Bibcode 2000Geo 28 1059K doi 10 1130 0091 7613 2000 28 lt 1059 DDFPTT gt 2 0 CO 2 Carroll M Kowalewski M Simoes MG Goodfriend GA 2003 Quantitative estimates of time averaging in terebratulid brachiopod shell accumulations from a modern tropical shelf Paleobiology 29 3 381 402 doi 10 1666 0094 8373 2003 029 lt 0381 QEOTIT gt 2 0 CO 2 S2CID 131237779 Kidwell SM Best MM Kaufman DS 2005 Taphonomic trade offs in tropical marine death assemblages Differential time averaging shell loss and probable bias in siliciclastic vs Carbonate facies Geology 33 9 729 732 Bibcode 2005Geo 33 729K doi 10 1130 G21607 1 Kosnik MA Hua Q Kaufman DS Wust RA 2009 Taphonomic bias and time averaging in tropical molluscan death assemblages Differential shell half lives in Great Barrier Reef sediment Paleobiology 35 4 565 586 doi 10 1666 0094 8373 35 4 565 S2CID 5839861 McCoy WD 1987 The precision of amino acid geochronology and paleothermometry Quaternary Science Reviews 6 1 43 54 Bibcode 1987QSRv 6 43M doi 10 1016 0277 3791 87 90016 3 Oches EA McCoy WD Clark PU 1996 Amino acid estimates of latitudinal temperature gradients and geochronology of loess deposition during the last glaciation Mississippi Valley United States Geological Society of America Bulletin 108 7 892 903 Bibcode 1996GSAB 108 892O doi 10 1130 0016 7606 1996 108 lt 0892 AAEOLT gt 2 3 CO 2 Miller GH Magee JW Jull AJ 1997 Low latitude glacial cooling in the Southern Hemisphere from amino acid racemization in emu eggshells Nature 385 6613 241 244 Bibcode 1997Natur 385 241M doi 10 1038 385241a0 S2CID 4312380 Kaufman DS 2003 Amino acid paleothermometry of Quaternary ostracodes from the Bonneville Basin Utah Quaternary Science Reviews 22 8 9 899 914 Bibcode 2003QSRv 22 899K doi 10 1016 S0277 3791 03 00006 4 McMenamin MA Blunt DJ Kvenvolden KA Miller SE Marcus LF Pardi RR 1982 Amino acid geochemistry of fossil bones from the Rancho La Brea Asphalt Deposit California Quaternary Research 18 2 174 183 Bibcode 1982QuRes 18 174M doi 10 1016 0033 5894 82 90068 0 Ogino T Ogino H October 1988 Application to forensic odontology of aspartic acid racemization in unerupted and supernumerary teeth Journal of Dental Research 67 10 1319 1322 doi 10 1177 00220345880670101501 PMID 3170888 S2CID 8664035 External links Edit The Wikibook Historical Geology has a page on the topic of Amino acid dating Active laboratories Edit Northern Arizona University Amino Acid Geochronology Laboratory Archived 2017 03 31 at the Wayback Machine University of Massachusetts Amino Acid Geochronology Laboratory The University of Colorado Amino Acid Geochronology Lab University of Delaware Research Group University of York BioArCh Madrid School of Mines Biomolecular Stratigraphy Laboratory Retrieved from https en wikipedia org w index php title Amino acid dating amp oldid 1130878496, wikipedia, wiki, book, books, library,

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