Please use this identifier to cite or link to this item: http://repositorio.unicamp.br/jspui/handle/REPOSIP/55798
Type: Artigo de periódico
Title: Chiroselective self-directed octamerization of serine: Implications for homochirogenesis
Author: Cooks, RG
Zhang, DX
Koch, KJ
Gozzo, FC
Eberlin, MN
Abstract: Serine undergoes chiroselective self-directed oligomerization to form a singly protonated octamer under positive ion electrospray conditions, as identified by ion trap tandem mass spectrometry. The experiments also show a series of higher-order clusters (metaclusters) corresponding to [(Ser(8)H)(n)](n+), n = 1, 2, 3. There is a magic number effect favoring formation of the protonated octamer over its homologues and also a strong preference for octamer formation from homochiral serine molecules. Collision-induced dissociation suggests that the protonated octamer is composed of four hydrogen-bonded dimers, stabilized by further extensive hydrogen bonding. Density functional calculations support this model and show that the protonated homochiral octamer is energetically stabilized relative to its possible fragments (dimer plus protonated hexamer, etc). The calculations also show that heterochiral octamers are less stable than homochiral octamers (e.g., the protonated 7:1 cluster is 2.1 kcal/mol less stable than the 8:0 analogue). The implications of these results for the origin of homochirality are discussed.
Country: EUA
Editor: Amer Chemical Soc
Rights: fechado
Identifier DOI: 10.1021/ac010284l
Date Issue: 2001
Appears in Collections:Artigos e Materiais de Revistas Científicas - Unicamp

Files in This Item:
File Description SizeFormat 
WOS000170274400026.pdf164.92 kBAdobe PDFView/Open


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.