Evidence for non-selective preservation anic matter in sinking marine particles.pdf

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autocatalytic production cycle of the homochiral template (Fig. 6). .................................................................
Cross-catalysis seems to result from the ability of these peptides to Evidence for non-selective
tolerate D-amino acid substitutions while maintaining a catalytically
active conformation24±26. We refer to this process as `dynamic preservation anic
stereochemical editing'.
Thus we have shown that even within the simple helical structure, matter in sinking marine particles
a peptide replicator can contain a rich degree of information that
enables it to display, at the molecular level, some of the basic John I. Hedges*, Jeffrey A. Baldock², Yves GeÂlinas*, Cindy Lee³,
characteristics of living systems, such as self-replication, homochir- Michael Peterson* & Stuart G. Wakeham§
ality, and resistance toward accumulation of errors (stereochemical
mutations). The link between these traits allows the replicator to * School of Oceanography, Box 357940, University of Washington, Seattle,
selectively amplify homochiral sequences. Therefore, chiroselectiv- Washington 98195-7940, USA
ity in peptide self-replication is a direct result plementary ² CSIRO Land and Water, PMB #2, Glen Osmond, South Australia 5064,
noncovalent interactions that pass on both binding and stereo- Australia
chemical information simultaneously. That suc