Hydrolysis of the ester linkage yields about 14 kJ/mol, whereas hydrolysis of each of the anhydride bond yields about 30 kJ/ mol. The a-ß and ß- y linkages are phosphoric acid anhydrides. The bond between the ribose and the a- phosphate is an ester linkage. The hydrolysis of ATP and other nucleoside triphosphates is an exergonic reaction. Others such as uridine triphosphate (UT P), guanosine triphosphate (GTP) and cytidine triphosphate (CT P) are used in specific reactions. Adenosine triphosphate (ATP) is the most widely used. NTPs are used as a source of chemical energy to drive many biochemical reactions.
The 3 phosphate groups are generally labelled as a, ß and y, starting from the ribose. These are referred to as nucleoside mono-, di- and triphos-phates and abbreviated as NMPs, NDPs and NTPs, respectively. Nucleotides may have one, two or three phosphate groups covalently linked at 5'-OH of ribose. When all the proteins was completely removed, it became clear that the new material was an acid.
With this favourable material, he further purified nuclein.
He soon found that a more convenient source of this material was salmon sperm. Miescher continued his studies when he returned to his native city, Basel, in Switzerland. These nuclei were then analyzed and found to have different composition from any cellular component then known. He observed microscopically that only the shrunken nuclei were left after the pepsin treatment the remainder of the cell had dissolved. From the pus on the bandages, he obtained the WBCs, which he then treated with gastric juice. A hospital at Tubingen supplied him with surgical bandages that had been peeled off purulent wounds. He chose to work with white blood corpuscles (WBCs) because they contained a large and easily observable nucleus. FRIEDRICH MIESCHER (LT, 1844-1895), a Swiss and a student of the eminent German chemist, Felix Hoppe-Seyler, became interested in the chemistry of the nucleus in 1860s. The elemental composition of the nucleic acids carbon, hydrogen, oxygen, nitrogen and, are phosphorus.u Like the proteins, the nucleic acids are biopolymers of high molecular weight with mononucleotide as their repeating units, just as amino acids are the repeating units of proteins. The nucleic acids are the hereditary determinants of living orgainsms.They are the macromolecules present in most living cells either in the free state or bound to proteins as nucleoproteins.What is nucleic acid and its historical perspective u Initially, nucleic acid was known by the term nuclein by Friedrich Miescher, a 25-year old Swiss chemist, isolated nuclei from pus cells (white blood corpuscles) and found that they contained a unknown phosphate-rich substance, which he named nuclein.
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