Nucleic Acid Metabolism

• Nucleotides, nucleosides and nucleic acids have specific structures.
• Digestion of nucleic acids involves the breakdown of nucleic acids into their constituent parts.
• De novo synthesis of purine nucleotides is the process by which purine nucleotides are synthesized from scratch.
• Salvage pathways of purine nucleotides involve the recycling of purine nucleotides.
• Catabolism of purine nucleotides involves the breakdown of purine nucleotides into their constituent parts.
• Pyrimidine nucleotide biosynthesis is the process by which pyrimidine nucleotides are synthesized.
• Urate crystals may also appear as kidney stones.
• Hyperuricemia, chronic elevation of blood uric acid levels, occurs in about 3% of the population as a consequence of impaired excretion of uric acid or overproduction of purines.
• In the periphery in the extremities, the solubility of uric acid decreases below 37 ° C and mono sodium urate crystals precipitate around the joints and in collagen-rich tissues such as kidney, cartilage, and ear lobe (tumors).
• The most common symptom of gout is arthritic pain in the joints as a result of monosodium urate deposition in cartilaginous tissue and inflammation around these crystals causes gouty arthritis.
• Degradation of pyrimidine nucleotides involves the breakdown of pyrimidine nucleotides into their constituent parts.
• The nucleotides consist of three kinds of building blocks: ribose sugar, purine or pyrimidine bases, and phosphate group.
• Pyrimidine ring is an aromatic organic compound with 2 nitrogens at 1 and 3 position of a six membered ring.
• Purine ring is an aromatic organic compound that consists of a pyrimidine ring and imidazole ring (C3H4N2).
• Purine bases are Adenine and guanine.
• Pyrimidine bases are Thymine, Uracil and Cytosine.
• D-ribose or deoxyribose are linked to purin or pyrimidine bases with a β-glycosidic bond.
• Addition of a phosphate group to the nucleoside forms a nucleotide.
• Nucleotides polymerize to form nucleic acids by linking the 3’ hydroxyl group of one nucleotide to the phosphate of another, eliminating one molecule of water (3’-5’ phosphodiester bond).
• A single nucleic acid strand is a phosphate-pentose backbone with purine and pyrimidine bases as side groups.
• DNA is a polymer of the deoxyribonucleotids composing A, C, G, and T, nucleotides which are joined through a backbone of alternating phosphate and deoxyribose residues.
• DNA consists of two strands of polynucleotides, coil around each other, forming a double helix which run in opposite direction.
• The nitrogen-containing base pairs occur in complementary each other in DNA.
• The hydroxyl group on the ribose causes RNA to be less stable than DNA.
• Mammals have two enzymes for carbamoyl phosphate synthesis: Carbamoyl phosphate synthetase II (CPS II), a cytosolic enzyme used for carbamoyl phosphate synthesis for pyrimidine biosynthesis, and Carbamoyl phosphate synthetase I, a mitochondrial enzyme dedicated in the urea cycle and arginine biosynthesis.
• Nucleic acids are the main information-carrying part of the cell, energy mediators of the cell, and determine the inherited characteristics of every living organism.
• DNA provides the genetic information for the cell and is inherently quite stable.
• Nucleic acids are dietarily non-essential, as they are synthesized in the body from intermediates.
• In the small intestine, complete digestion of Nucleic acids takes place, with the specific Enzymes present in the Pancreatic and Intestinal juice.
• The purine bases are then oxidized to uric acid, which may be absorbed and excreted in the urine.
• DNA and RNA have different structures: DNA is double-stranded and RNA is single-stranded.
• Ingested nucleic acids and nucleotides are degraded in the intestinal tract to mononucleotides, which are then absorbed or converted to purine and pyrimidine bases.
• Nucleoproteins are formed when Nucleic acid and Protein combine.
• Hydrogen bonds, van der Walls and hydrophobic bonds stablize the structure of double helix.
• DNA can be folded like a hairpin and base paired with bases Adenin, guanin, cytosine, thymine.
• DNA is made of deoxyribose sugar and RNA is made of ribose sugar.
• In the stomach, gastric HCl denatures (hydrogen bonds) of Nucleic acids.
• RNA can be folded like a hairpin and base paired with bases Adenin, guanin, cytosine, Uracil.
• RNA is the genetic material of certain viruses and is also found in all living cells, where it plays an important role in certain processes such as the protein synthesis.
• Nucleic acids comprise four nucleotides A, C, G, and U joined through a backbone of alternating phosphate and ribose sugar residues.