Nucleotides prebiotic

Saladino R, Crestini C, Costanzo G, DiMauro E (2005) On the Prebiotic Synthesis of Nucle-obases, Nucleotides, Oligonucleotides, Pre-RNA and Pre-DNA Molecules. 259 29-68 Santos I, Paulo A, Correia JDG (2005) Rhenium and Technetium Complexes Anchored by Phosphines and Scorpionates for Radiopharmaceutical Applications. 252 45-84 Santos M, see Szathmdry E (2005) 259 167-211... 

Although the results of all experiments so far carried out on nucleoside synthesis under prebiotic conditions have been disappointing, the next step, to give the nucleotides, has been carried out using nucleosides synthesized in today s laboratories. There are two preconditions for nucleotide syntheses ... 

The RNA world hypothesis caused prebiotic phosphate chemistry to become an attractive research area again unfortunately, no clear evidence for a realistic nucleotide synthesis under the simplified conditions of a primitive Earth has yet appeared. Important work on nucleoside phosphorylation has, however, been done. It is important to distinguish between ... 

Zubay and Mui (2001) have pointed out an important, but as yet unsolved, problem of prebiotic nucleotide synthesis the nitrogen-containing nucleobases very probably have HCN as the main precursor for their construction. In the case of... 

Although the pre-RNA world is now much more the centre of scientific attention in prebiotic chemistry, there have been several attempts in recent years to understand the synthesis of oligonucleotides from the normal nucleotides by using simulation experiments (Ferris, 1998). In condensation reactions in aqueous media, there is always competition between synthesis and hydrolysis synthesis is generally only successful when supported by catalysts. 

The RNA world was the first biological world. If this is the case, we can learn or predict but little about the prebiotic chemistry of the RNA world from the biochemistry of today perhaps only the fact that the formation and polymerisation of nucleotides were once prebiotic processes. Thus Orgel is not of the... 

Moderately simple syntheses have been performed for the purines cytosine and uracil but nothing seems to work as a prebiotic synthesis of the pyrimidines. Then adding the sugar ribose to the base makes them nucleosides and one phosphoric acid residue makes it a nucleotide, or specifically a mononucleotide a rare but curiously important sequence of events in present-day life but perhaps not for prebiotic chemistry and early life forms. 

Figure 4.8 The hypothetical prebiotic fusion between nucleotide- and peptide-containing vesicles.

Creation of prebiotic soup, including nucleotides, from components of Earth s primitive atmosphere... 

How did these small prebiotic organic molecules grow into large polymeric substances such as peptides, RNA, and so on It is important to recognize that by whatever reactions polymerization occurred, they had to be reactions that would occur in an essentially aqueous environment. This presents difficulties because condensation of amino acids to form peptides, or of nucleotides to form RNA or DNA, is not thermodynamically favorable in aqueous solution. 

Imidazole is a reasonable prebiotic compound, since it can be synthesized from glyoxal + 2NH3 + H2CO or from cyanoacetylene + NH3 + ultraviolet light. However, it is not clear whether large amounts were present in the primitive ocean. It may be that the template polymerizations described below were carried out slowly using nucleotide polyphosphates. Such experiments are difficult to carry out in the lab because of the long time needed. 

Prebiotic self-association was inevitable as well as uniform at the most fundamental level differences are the consequence of higher level organization, i.e., the order rather than the ingredient. Once a nucleic acid sequence had been established and became part of the memory of an organism, it was maintained by the mode of complimentary self reproduction for as long as the species lasted. Again it is the uniform distance of hydrogen bonds that line up the nucleotide bases for accurate reproduction. 

On the Prebiotic Synthesis of Nudeobases, Nucleotides, Oligonucleotides, Pre-RNA and Pre-DNA Molecules... 

Keywords Origin of life Prebiotic synthesis Nucleic bases Nucleotides Oligonucleotides... 

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