Croatica Chemica Acta, Vol. 62 No. 2A, 1989.
Pregledni rad
Electroweak Bioenantioselection
A. J. MacDermott
; Physical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, U. K.
G. E. Tranter
; Wellcome Research Laboratories, Wellcome Foundation, Beckenham, Kent BR3 3BS, U. K.
Sažetak
This paper reviews evidence for the view that biomolecular
chirality was determined not by chance but by the electroweak
interaction. Other influences (such as the Earth's magnetic and
gravitational fields, or circularly polarized light) are either falsely
chiral or else even-handed on a time and space average, leaving
the weak interaction as the only consistent universal chiral influence.
Electroweak bioenantioselection could occur either through
p-radiolysis or through the small parity-violating energy differences
(PVED) between enantiomers. The PVED produces an electroweak
enantiomeric excess of only 10-17, but this can be amplified
to homochirality within 104 years by the powerful Kondepudi
mechanism. Calculations of the PVED show that the natural
L-amino acids are more stable than their »unnatural« n-enantiomers,
and natural n-glyceraldehyde and D-deoxyribose are also
PVED-stabilized. The PVED can also explain the observed 1%
excess of l(-)-quartz, which, through pre-biotic mineral catalysis,
could increase the electroweak enantiomeric excess to 10-4.
Ključne riječi
Hrčak ID:
175391
URI
Datum izdavanja:
30.6.1989.
Posjeta: 630 *