Kinetics of amino acid racemization in Sequoiadendron giganteum heartwood

✍ Scribed by Michael H. Engel; John E. Zumberge; Bartholomew Nagy

• Book ID: 102982652
• Publisher: Elsevier Science
• Year: 1977
• Tongue: English
• Weight: 505 KB
• Volume: 82
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(77)90179-8

✦ Synopsis

Activation energies and Arrhenius frequency factors were calculated for the racemization reaction of four bound amino acids (asp, glu, pro, phe) isolated from sequoia heartwood, by using elevated temperature rate constants. In addition, a first-order rate constant of 2.1 x 10m5 yea+' was calculated for the racemization of bound aspartic acid from the extent of racemization in dendrochronologically dated sequoia heartwood samples. Because the racemization reaction is temperature dependent, an average temperature which the bound aspartic acid in sequoia had experienced during the past -2200 years was obtained. This value agrees with modem temperatures near the sample location and estimated paleotemperatures during the past -2000 years.

' Mail reprint requests to Professor Bartholomew Nagy. 415 Copynght '5' 1977 by Academic Prerr.

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