Deoxyribonucleic acid chemical synthesis

The initial conversion of light into chemical energy takes place in the thylakoid membrane. Besides the chlorophylls and series of electron carriers, the thylakoid membrane also contains the enzyme adenosine triphosphate (ATP) synthase. The enzymes that are responsible for the actual fixation of C02 and the synthesis of carbohydrate reside in the stroma that surround the thylakoid membrane. The stroma also contains deoxyribonucleic acid (DNA), ribonucleic acid (RNA), and ribosomes that are essential for protein synthesis [37]. 

DNA effects Damage to DNA (Deoxyribonucleic acid) by a chemical or material may result in genotoxic effects such as mutations, which in turn may lead to carcinogenicity. Damage to DNA causes the cell to manufacture new DNA to compensate for the loss or damage. This can be assessed by evaluating the formation of newly synthesized DNA. Unscheduled DNA Synthesis... 

Genotoxic effects have been reported in animals treated with 3,3 -dichlorobenzidine. A single dose of 3,3 -dichlorobenzidine (1,000 mg/kg) administered to male and pregnant female mice induced micronuclei in polychromatic erythrocytes in the bone marrow of the males and in the liver of the fetuses, but not in bone marrow of the dams (Cihak and Vontorkova 1987). A micronucleus test is performed to detect a chemical s ability to induce chromosomal aberrations. However, the relevance of micronuclei formation to human health is not known. The reason for the lack of effect of 3,3 -dichlorobenzidine on bone marrow micronuclei formation in the mothers is unclear, but it may be related to deficiencies in the metabolic activation of 3,3 -dichlorobenzidine in female mice. The relative importance of pregnancy is unknown since the study did not evaluate nonpregnant females. In another study, an increase in unscheduled deoxyribonucleic acid synthesis (UDS) was observed in cultured liver cells from male mice previously pretreated orally with single doses of 500 mg/kg 3,3 -dichlorobenzidine no response was observed at a dose of 200 mg/kg (Ashby and Mohammed 1988). 

Deoxyribonucleic acid (DNA) belongs to a group of chemicals called the nucleic acids (Figure 15.26) They are also biopolymers. DNA controls the prote synthesis within your cells. When you eat a food containing proteins, such as meat or cheese, your digestive enzymes break down the proteins present into individual amino acids. The DNA in your cells controls the order in which the amino acids are repolymerised to make the proteins you need ... 

Lehman, I. R., Zimmerman, S. B., Adler, J., Bessman, M. J., Simms, E. S., and Kornberg, A. (1958). Enzymatic synthesis of deoxyribonucleic acid V. Chemical composition of enzymatically synthesized deoxyribonucleic acid. Proc. Natl. Acad. Sci. USA 44, 1191-1196. 

Fundamental knowledge of the structure, function and mechanism of DNA-modifying enzymes has been important not only in understanding how these enzymes perform a myriad of chemical reactions Ml vZvo but also for the development of the field of recombinant DNA technology. The functions of the major groups of enzymes in deoxyribonucleic acid synthesis, hydrolysis and modification are reviewed, as well as some structural and mechanistic aspects of the restriction endonucleases, ligases and polymerases. 

The information about a living system is passed to its future generation through a polymer called deoxyribonucleic acid (DNA). Together with other similar nucleic acids called the ribonucleic acids (RNA), DNA is also responsible for the synthesis of the various proteins needed by the ceil to carry out its life functions. From the chemical composition of DNA and its X-ray crystallography photos, its structure was elucidated by JAMES WATSON (born 1928), FRANCIS CRICK (1916 - 2009), MACJRICE WILKINS (1916 - 200 ) and "ROSALIND FRANKLIN (1920 -1958) in... 

The genetic information is contained within the chemical structure of DNA, deoxyribonucleic acid, namely the sequence of bases along the polynucleotide chain. RNA, ribonucleic acid, is used by an organism to act as a messenger between the genes and the site of protein synthesis, the ribosome. The genes of all cells and many viruses are made of DNA. 

The directed synthesis of deoxyribonucleic acid (DNA) and its manipulation for genetic engineering would be impossible without enzyme catalysis. There is a range of restriction enzymes which can break DNA strands at specific points defined by the local base sequence, as well as ligases which can rejoin the broken ends where new base sequences are inserted, and they are essential catalysts. They complement the chemical synthesis of the oligonucleotides (small segments of DNA) which are inserted. A discussion of the technique is outside the scope of this chapter, largely because the... 

Nanotubes represent spatially defined nano-containers with chemically defined inside and outside properties and up to two openings for mass exchange with the surrounding environment. Such functional geometric objects have attracted the attention of synthetic chemists for many years and many different synthetic approaches have been exploited to create such structures. Most approaches can be roughly divided into covalent and non-covalent synthetic strategies. The latter can be formed from, for example, stacked macrocycles or via self-assembly of low molecular weight amphiphiles, " peptides,proteins,or deoxyribonucleic acids (DNA). Several excellent articles have been published that review the field of nanotube synthesis up to the year 2005. " ... 

We ve now covered the last of the four major classes of biomolecules—the nucleic acids, DNA (deoxyribonucleic acid) and RNA (ribonucleic acid). So much has been written and spoken about DNA in the media that our focus has been on the chemical details of DNA sequencing, synthesis, and metabolism rather than on simpler fundamentals. 

We have seen that the amino acid sequence in a protein determines that protein s structure and function. If the amino acid sequence is incorrect, the protein is unlikely to function properly. How do cells in living organisms synthesize the many thousands of different required proteins, each with the correct amino acid sequence The answer lies in nucleic acids, molecules that serve as blueprints for protein synthesis. Nucleic acids employ a chemical code to specify the correct amino acid sequences for proteins. Nucleic acids are broadly divided into two types deoxyribonucleic acid, or DNA, which exists primarily in the nucleus of the cell and ribonucleic acid, or RNA, which exists throughout the cell. 

Over the last 30 years or so, the chemical synthesis of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) has constituted one of the most challenging problems in the field of the synthetic organic chemistry of natural products. In more recent times, attention has been focused not on natural nucleic acid fragments, but on the preparation of nucleic acids bearing modified internucleotidic linkages or modified bases in an effort to enhance stability to nucleases and increase cellular uptake. 

Optimal Strategies for Chemical and Enzymatic Synthesis of Bihelical Deoxyribonucleic Acids"... 

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