Origin of Homochirality of Amino Acids

67 Pages·2009·3.93 MB·English

Origin of Homochirality
of Amino Acids
Rafida Nossoni
Feb 25th, 2009
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Discovery of Chirality
Introduced in 1884
Discovered in 1848
by Lord Kelvin
by Lewis Pasteur
What is Chirality ?
Point Chirality Atropisomerism
Axial Chiraly Helicity
Clayden, J; Greeves , N; Warren. S; Worthers . P. Organic Chemistry. Oxford University Press
Thalidomide Tragedy
O O
H H
O O
N N
HN NH
O O
O O
R-Thalidomide S-Thalidomide
(sleep inducing) (teratogenic)
http://globalphilosophy.blogspot.com/2008/04/thalidomide-was-one-of-greatest-cases.html
Amino Acids Chirality
Clayden, J; Greeves , N; Warren. S; Worthers . P. Organic Chemistry. Oxford University Press
Homochirality
(cid:1) Homochirality is a term to describe a group of molecules that
possess the same sense of chirality.
Cohen, J. European Review, 2005, 13, 49–59.
Biological Homochirality
Enzyme DNA RNA
Cohen, J. European Review, 2005, 13, 49–59
Outline
(cid:1) Origin of life
Physical suggestion
(cid:2)
(cid:1) RNA World hypothesis
Origin of D-ribose
(cid:2)
(cid:1) Synthesis of protein in biological systems
(cid:1) Two Different methods to approach homochirality
Model on the mineral surface
(cid:2)
Minihelix as a progenitor of tRNA
(cid:2)
Outline
(cid:1) Origin of life
Physical suggestion
(cid:2)
(cid:1) RNA World hypothesis
Origin of D-ribose
(cid:2)
(cid:1) Synthesis of protein in biological systems
(cid:1) Two Different methods to approach homochirality
Model on the mineral surface
(cid:2)
Minihelix as a progenitor of tRNA
(cid:2)