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Origin of homochirality

Chirality at surfaces can be manifested in a number of forms including the intrinsic chirality of the surface structure and even the induction of chirality via the adsorption of achiral molecules onto achiral surfaces. The ability of STM to probe surfaces on a local scale with atomic/molecular resolution has revolutionized the understanding of these phenomena. Surfaces that are globally chiral either due to their intrinsic structure or due to the adsorption of chiral molecules have been shown by STM to establish control over the adsorption behavior of prochiral species. This could have profound consequences for the understanding of the origin of homochirality in life on Earth and in the development of new generations of heterogeneous chiral catalysts that may, finally, make a substantial impact on the pharmaceutical industry. [Pg.25]

In accordance with the autocatalytic process, matrices are again formed. It is surprising that the autocatalysis decreases when only 1 of the 15 building blocks of the peptide has the opposite handedness, e.g., when the N-peptide fragment contains one D-amino acid as well as the 14 L-amino acids. These experimental results show that such a system is able to form homochiral products via self-replication. It can be assumed that similar mechanisms influenced the origin of homochirality on Earth (Saghatelian et al., 2001 Siegel, 2001). [Pg.142]

Greenberg, J. M. Chirality in interstellar dust and in comets Life from dead stars in Physical Origin of Homochirality in Life Cline, D. B., Ed. American Institute of Physics Woodbury, NY, 1996, pp 185-210. [Pg.205]

Avetisov, V. A. Spontaneous mirror symmetry breakingvia enantioselective autocatalysis in Physical Origin of Homochirality in Life,... [Pg.205]

It has already been mentioned that the origin of homochirality in nature can be viewed in terms of the controversy between determinism and contingency. Is the L form of amino acids determined by some physical law of nature or is it a matter of chance in chemical evolution ... [Pg.53]

I have mentioned that there are two main aspects to consider on the origin of homochirality, one being the breaking of symmetry, the other the preservation and amplification of this initial inbalance. The latter will be considered further in the next chapter, which deals with macromolecules. [Pg.56]

It is worthwhile also mentioning that the origin of homochirality has been viewed in terms of a bifurcation scenario (Kondepudi and Prigogine, 1981 Kondepudi et al, 1985). In this case, the homochirality present on Earth would be a product of contingency. [Pg.107]

Keywords Asymmetric autocatalysis Amplification of chirality Pyrimidyl alkanol Automultiplication Origin of homochirality... [Pg.2]

Soai K, Sato I, Shibata T (2004) Asymmetric autocatalysis and the origin of homochirality of biomolecules. In Malhotra SV (ed) Methodologies in asymmetric catalysis. J Am Chem Soc, Washington, DC, p 85... [Pg.31]

Since Pasteur s discovery this problem of the origin of homochirality in life has attracted the attention of many scientists in relation to the origin of life itself [3,5-7]. Japp expected a directive force when fife first arose [3], and various directive forces have been proposed later, such as different intensities of circularly polarized light in a primordial era, adsorption on optically active crystals, or parity breaking in the weak interaction. However, the expected degree of chiral asymmetry or the value of the enantiomeric excess (ee) turns out to be very small [6], and one needs a mechanism to amplify ee enormously to a level of homochirality. [Pg.99]

Another scenario for the origin of homochirality was suggested by Pearson [8,9] such that chance breaks the chiral symmetry. Though the mean number of right- and left-handed enantiomers are the same, there is a nonzero probability of deviation from the equal populations of both enantiomers. The probability of establishing homochirality in a macroscopic system is, of course, very small [10], but chance produces a slight majority of one type of enantiomer and asymmetric compounds when they have once arisen act as breeders, with a power of selecting their own kind of asymmetry form [8,9]. In this scenario, produced enantiomer acts as a chiral catalyst for the production of its own kind and hence this process should be autocatalytic. [Pg.99]

Cline DB (ed) (1996) Physical origin of homochirality in life. AIP Proc 378, New York... [Pg.186]

Bailey J (2001) Astronomical sources of circularly polarized light and the origin of homochirality. OrigLife Evol Biosph 31 167-183... [Pg.302]

Cline DB, ed. Physical Origin of Homochirality in Life. Am. Inst. Physics. New York, 1996. [Pg.126]

The question of the origin of homochirality is widely discussed but remains unproven. The proposal that peptide nucleic acid in which a peptide chain replaced the phosphodiester backbone had a role in the prebiotic origin of life prior to an RNA world has not been tested experimentally. [Pg.20]

Thus, the origin of homochirality of biomolecules might have involved the inherently achiral nucleotide base cytosine. In conjunction with the subsequent amplification of chirality by asymmetric autocatalysis, spontaneously formed chiral crystals of achiral cytosine acted as an origin of homochirality in biomolecules. The structure of cytosine indicates that the Nl-atom may be prochiral (marked by an asterisk in Fig. 3.5). In contrast, uracil and adenosine do not have asymmetric atoms. It remains unknown whether the distantly related structure of guanine can... [Pg.29]

Cooper G, Kimmich N, Belisle W et al (2001) Carbonaceous meteorites as a source of sugar-related organic compounds for the early earth. Nature 414 879-883 Cordova A, Engqvist M, Ibrahem I et al (2005) Plausible origins of homochirality in the amino acid catalyzed neogenesis of carbohydrates. Chem Comm 2047-2049 Cronin JR, Pizzarello S (1997) Enantiomeric excesses in meteoritic amino acids. Science 275 951-955 Di Guilio M (1997) On the RNA world evidence in favour of an early ribonucleopeptide. J Mol Evol 45 571-574... [Pg.74]

Kawasaki T, Suzuki K, Hakoda Y et al (2008) Achiral nucleobase cytosine acts as an origin of homochirality of biomolecules in conjunction with asymmetric autoctalysis. Angew Chem Int Ed 47 496 199... [Pg.75]

Bonner, W. (1996) Homochirality and life. In Cline, D.B. (ed.). Physical Origin of Homochirality, pp. 266-282. American Institute of Physics, New York. [Pg.472]

Blackmond, Donna G. Asymmetric Autocatalysis and its Implications for the Origin of Homochirality. Proceedings of the National Academy of Sciences 101 (2004) 5,732-36. This review describes the kinetics of autocatalysis and possible mechanisms for spontaneous resolution of mixtures having a miniscule excess of one enantiomer. [Pg.403]

PizzareUo, Sandra. The Chemistry of Life s Origin A Carbonaceous Meteorite Perspective. Accounts of Chemical Research 39 (2006) 231-37. This brief review article discusses the possible origins of homochirality on Earth. [Pg.404]

There are many natural minerals and salts that posses optical activity in their crystalline state owing to their chiral lattices, sueh as quartz, einnabar, mica, chlorates, bromates, and iodates. Crystal chirality of other minerals, like aluminosilicates, such as zeolites, were not investigated, but these minerals are considered by many investigators as possible sourees of chirality and the origin of homochirality in our biosphere The optieal activities of clays have not revealed reliable evidence of chirality and therefore they do not play any positive role in our understanding of the origin or of the amplification of homochirality in nature. [Pg.2]

Goldanskii V.l. (1996) Formaldehyde as hypothetical primer of biohomochirality, in Physical Origin of Homochirality in Life, Amer. Inst. Phys. Conferences, Santa Monica CA, Proceedings 379, 1995 (Cline D.B. (ed.), AlP Press, Woodbury, N.Y. pp. 50-54. [Pg.21]

In similar ways circular polarized light irradiation of very low efficacy combined with enantiomorphic crystals and autocatalytic amplification reactions, could be the origin of homochirality of organic molecules (Bonner ). [Pg.55]

Klabunovskii E.I. ( 2001) Can enantiomorphic crystals like quartz play the role in the origin of homochirality on Earth, Astrohiology 1, 127-131. [Pg.60]

Klabunovskii E.I. and Thiemann W. (2000) The role of quartz in the origin of optical activity on Earth, Origin Life Evol. Biosphere 30, 431-434. Bonner W.A. (1996) The quest for chirality. Physical origin of homochirality in life, Amer. Inst. Phys. Conf, Santa Monica CA, Febr. 1995, Proceedings, Cline D.B. (ed.). Press Woodbury, N.Y., p. 17-49. Avalos M., Babiano R., Cintas P., Jimenez J.L. and Palacios J.C. (2000) Chiral autocatalysis where stereochemistry meets the origin of life, Chem. Commun. 887-892. [Pg.62]

Bonner, W.A. (1995) The quest for chirality, m. Physical origin of homochirality in life. Conference Proceedings, 379. Santa Monica, Cal., American Institute of Physies Press, Woodbury, N.Y., p. 17-49 Bonner, W.A. (1990) Attempted asymmetric electrochemical reductions in magnetic-fields. Origins of Life and Evolution of Biosphere 20,1-13 Bonner, W.A. (1990) The eleetrochemical reduction of phenylglyoxylic acid in a magnetic-field, Electrochem. Acta 35, 683-684. [Pg.274]

Blackmond DG Asymmetric autocatalysis and its implications for the origin of homochirality. Proc Natl Acad Sci USA 2004, 101(l6) 5732-5736. [Pg.94]


See other pages where Origin of homochirality is mentioned: [Pg.275]    [Pg.377]    [Pg.203]    [Pg.260]    [Pg.67]    [Pg.586]    [Pg.22]    [Pg.62]    [Pg.117]    [Pg.122]    [Pg.75]    [Pg.125]    [Pg.229]    [Pg.325]    [Pg.344]    [Pg.59]    [Pg.531]   
See also in sourсe #XX -- [ Pg.39 , Pg.56 ]




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