Possible Origins of Biohomochirality

The origin of biohomochirality and the reasons, why this form of homochirality (L-amino acids, D-sugars, etc.) and not the mirror image case was preferred have been the subject of numerous hypotheses, but a definitive solution to this riddle that might be strongly correlated with the origin of life itself has not been found to date. In this paper different pathways trying to explain the origin of biohomochirality are reviewed, inter alia the chance hypothesis, spontaneous resolution mechanisms, preferential adsorption on chiral surfaces, the interaction of interstellar organic dust clouds with circularly polarised light and subsequent transport to earth via meteorites, and a possible preference for one enantiomeric form due to parity violation in weak nuclear interactions. In the Salt-Induced Peptide Formation (SIPF) reaction a preference for the L-form of several amino acids was observed. The active complex in this reaction contains a central copper ion which, due to its high atomic number, provides larger parity violating energy differences (PVED's). In combination with the geometry of this complex that features a central chirality at this copper ion and further chiral influence through chiral amino acid ligands a completely new aspect to explain biohomochirality is presented.