After completing this chapter, students will be able to: Know the basic structures of nucleosides, nucleotides, and nucleic acids; know the difference between the syn and anti conformation of nucleotides and nucleosides; know the actual structures of the 4 deoxyribonucleotide triphosphates (dATP, dCTP, dGTP, dTTP), and the 4 ribonucleotide triphosphates (ATP, CTP, GTP, UTP). Know which ones are purines and which ones are pyrimidines. Draw all in anti conformation;. | Chapter 19 (part 1) Nucleic Acids Information encoded in a DNA molecule is transcribed via synthesis of an RNA molecule The sequence of the RNA molecule is "read" and is translated into the sequence of amino acids in a protein. Nucleic Acids Are Essential For Information Transfer in Cells Central Dogma of Biology Nucleic Acids First discovered in 1869 by Miescher. Found as a precipitate that formed when extracts from nuclei were treated with acid. Compound contained C, N, O, and high amount of P. Was an acid compound found in nuclei therefore named nucleic acid Nucleic Acids 1944 Oswald, Avery, MacLeod and McCarty demonstrated that DNA is the molecule that carrier genetic information. 1953 Watson and Crick proposed the double helix model for the structure of DNA Nucleic Acids Nucleic acids are long polymers of nucleotides. Nucleotides contain a 5 carbon sugar, a weakly basic nitrogenous compound (base), one or more phosphate groups. Nucleosides are similar to nucleotides but have no . | Chapter 19 (part 1) Nucleic Acids Information encoded in a DNA molecule is transcribed via synthesis of an RNA molecule The sequence of the RNA molecule is "read" and is translated into the sequence of amino acids in a protein. Nucleic Acids Are Essential For Information Transfer in Cells Central Dogma of Biology Nucleic Acids First discovered in 1869 by Miescher. Found as a precipitate that formed when extracts from nuclei were treated with acid. Compound contained C, N, O, and high amount of P. Was an acid compound found in nuclei therefore named nucleic acid Nucleic Acids 1944 Oswald, Avery, MacLeod and McCarty demonstrated that DNA is the molecule that carrier genetic information. 1953 Watson and Crick proposed the double helix model for the structure of DNA Nucleic Acids Nucleic acids are long polymers of nucleotides. Nucleotides contain a 5 carbon sugar, a weakly basic nitrogenous compound (base), one or more phosphate groups. Nucleosides are similar to nucleotides but have no phosphate groups. Pentoses of Nucleotides D-ribose (in RNA) 2-deoxy-D-ribose (in DNA) The difference - 2'-OH vs 2'-H This difference affects secondary structure and stability Nitrogenous Bases Bases are attached by b-N-glycosidic linkages to 1 carbon of pentose sugar – (Nucleoside) Nucleosides Base is linked via a b-N-glycosidic bond The carbon of the glycosidic bond is anomeric Named by adding -idine to the root name of a pyrimidine or -osine to the root name of a purine Conformation can be syn or anti Sugars make nucleosides more water-soluble than free bases Anti- conformation predominates in nucleic acid polymers Nucleotides Phosphate ester of nucleosides The plane of the base is oriented perpendicular to the plane of the pentose group Other Functions of Nucleotides Nucleoside 5'-triphosphates are carriers of energy Bases serve as recognition units Cyclic nucleotides are signal molecules and regulators of cellular metabolism and reproduction ATP is central to energy metabolism GTP .
