Premium
On the Prebiotic Synthesis of D ‐Sugars Catalyzed by L ‐Peptides: Assessments from First‐Principles Calculations
Author(s) -
Cantillo David,
Ávalos Martín,
Babiano Reyes,
Cintas Pedro,
Jiménez José L.,
Palacios Juan C.
Publication year - 2012
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.201200466
Subject(s) - glycolaldehyde , prebiotic , autocatalysis , chemistry , catalysis , ribose , xylose , stereochemistry , sugar , organic chemistry , biochemistry , enzyme , fermentation
What accounts for a particular chiral selection in the case of a few sugars of prebiotic relevance, thereby mirroring the asymmetry observed in nature? By using first‐principles calculations, the generation of pentoses from glycolaldehyde (the initial product of the autocatalytic formose reaction), which has been detected in outer space), has been modeled by using L ‐Val‐ L ‐Val as a primeval catalyst. Our theoretical study provides insight into the mechanism of this reaction and satisfactorily explains a few key molecular events. Our rationale agrees with the reported experimental data and shows that the D ‐configuration is only favored for ribose. L ‐pentoses are usually favored in the presence of L ‐configured dipeptides, as observed experimentally, although no chiral selection could be observed in the case of xylose. These results confirm that a prebiotic sugar soup could be fine‐tuned in the presence of shorter peptides as catalysts and that D ‐ribose would have also resulted in an advantageous imbalance for further amplification and chemical evolution.