Nucleic Acid Structure & Function PDF

FEU Biochemistry Property. All forms of replicatin are prohibited. Seek approval from Ms. Jessa Natividad and Ms. Erika Viloria 8/13/24 Nucleic Acid Structure &...

FEU Biochemistry Property. All forms of replicatin are prohibited. Seek approval from Ms. Jessa Natividad and Ms. Erika Viloria 8/13/24 Nucleic Acid Structure & Function Lab Module 6 Far Eastern University IAS – Dept. of Mathematics Biochemistry Cluster 1 Outline Nucleic Acids Introduction Nucleotide Structure Nucleic Acid Structure DNA RNA DNA Structure RNA Structure Base Pairing Types 2 1 FEU Biochemistry Property. All forms of replicatin are prohibited. Seek approval from Ms. Jessa Natividad and Ms. Erika Viloria 8/13/24 Nucleic Acids 3 Introduction Nucleic acids are the biomolecules responsible for the transfer of genetic information. They are polymers of a repeating unit called a nucleotide. 4 2 FEU Biochemistry Property. All forms of replicatin are prohibited. Seek approval from Ms. Jessa Natividad and Ms. Erika Viloria 8/13/24 Introduction Nucleic acids are also involved in energy metabolism, such as in ATP, UTP and GTP. 5 Nucleotide Structure Nucleotides are the monomers used in nucleic acids. They are composed of a nitrogenous base, a pentose sugar, and a phosphate group. 6 3 FEU Biochemistry Property. All forms of replicatin are prohibited. Seek approval from Ms. Jessa Natividad and Ms. Erika Viloria 8/13/24 Nucleotide Structure Nitrogenous Bases There are two (2) types of heterocyclic, nitrogenous bases, depending on the parent compound they were derived from. Pyrimidines – one ring, six atoms Purines – two rings, nine atoms 7 Nucleotide Structure Nitrogenous Bases (2-oxy-4-oxy (2-oxy-4-oxy-5-methyl (2-oxy-4-amino pyrimidine) pyrimidine) pyrimidine) 8 4 FEU Biochemistry Property. All forms of replicatin are prohibited. Seek approval from Ms. Jessa Natividad and Ms. Erika Viloria 8/13/24 Nucleotide Structure Nitrogenous Bases (6-amino purine) (2-amino-6-oxy purine) 9 Nucleotide Structure Pentose Sugar Two pentose sugars are used for nucleotides. Ribose – for RNA 2-Deoxyribose – for DNA 10 5 FEU Biochemistry Property. All forms of replicatin are prohibited. Seek approval from Ms. Jessa Natividad and Ms. Erika Viloria 8/13/24 Nucleotide Structure Phosphate Group Phosphate groups of nucleotides are derived from phosphoric acid (H3PO4). Under cellular conditions, it exists in its ionic form, HPO42-. 11 Nucleotide Structure In a nucleotide, the bonds that link the three groups use the carbon atoms of the pentose sugar as the reference. The pentose carbons are designated with a number and a prime. 12 6 FEU Biochemistry Property. All forms of replicatin are prohibited. Seek approval from Ms. Jessa Natividad and Ms. Erika Viloria 8/13/24 Nucleotide Structure Nitrogenous bases are linked to C1 of the pentose (1’) via a glycosidic bond. Nitrogenous bases linked to a pentose are referred to as nucleosides. Phosphate groups are linked to C5 of the pentose (5’) via an ester bond. 13 Nucleotide Structure Nomenclature 14 7 FEU Biochemistry Property. All forms of replicatin are prohibited. Seek approval from Ms. Jessa Natividad and Ms. Erika Viloria 8/13/24 Nucleotide Structure Ribonucleotides Deoxyribonucleotide 15 Nucleic Acid Structure Nucleotides are linked through their sugar and phosphate groups, referred to as nucleic acid backbone. DNA Backbone RNA Backbone 16 8 FEU Biochemistry Property. All forms of replicatin are prohibited. Seek approval from Ms. Jessa Natividad and Ms. Erika Viloria 8/13/24 Nucleic Acid Structure Nucleotides are linked from 3’ carbon to the 5’ carbon via a phosphodiester bond. The nucleotide with the free phosphate groups is called the 5’ end. The nucleotide with the free OH group is called the 3’ end. By convention, nucleic acids are written from 5’ to 3’. 17 Deoxyribonucleic Acid (DNA) 18 9 FEU Biochemistry Property. All forms of replicatin are prohibited. Seek approval from Ms. Jessa Natividad and Ms. Erika Viloria 8/13/24 Deoxyribonucleic Acid Deoxyribonucleic acids (DNA) Nitrogenous Bases: G, C, A, T Pentose Sugar: 2-Deoxyribose Found in the nucleus For storage and transfer of genetic information Passed from one cell to another during cell division 19 DNA Structure Primary Structure Refers to the single strand nucleotide sequence, written from 5’ to 3’ Secondary Structure Refers to the double stranded helix structure One strand runs from 5’ to 3’ and the other runs from 3’ to 5’ (anti-parallel) Stabilized by hydrogen bonds between nitrogenous bases of the two strands Backbone is oriented outwards, bases are oriented inwards 20 10 FEU Biochemistry Property. All forms of replicatin are prohibited. Seek approval from Ms. Jessa Natividad and Ms. Erika Viloria 8/13/24 DNA Structure 21 Base Pairing In double stranded DNA (dsDNA), the nitrogenous bases on one strand are always paired with their complementary bases on the other strand. Guanine is always paired to cytosine with three (3) hydrogen bonds. Adenine is always paired to thymine with two (2) hydrogen bonds. 22 11 FEU Biochemistry Property. All forms of replicatin are prohibited. Seek approval from Ms. Jessa Natividad and Ms. Erika Viloria 8/13/24 Base Pairing Example: ssDNA: 5’-A-A-T-G-C-A-G-C-T-3’ Complement: 3’-T-T-A-C-G-T-C-G-A-5’ ssDNA: 5’-A-A-G-C-T-A-G-C-T-T-A-C-T-3’ Complement: 3’-T-T-C-G-A-T-C-G-A-A-T-G-A-5’ 23 Base Pairing In dsDNA: %A is always equal to %T %G is always equal to %C Example: Human DNA contains 30% adenine, 30% thymine, 20% guanine and 20% cytosine. 24 12 FEU Biochemistry Property. All forms of replicatin are prohibited. Seek approval from Ms. Jessa Natividad and Ms. Erika Viloria 8/13/24 Ribonucleic Acid (DNA) 25 Ribonucleic Acid Ribonucleic acids (RNA) Nitrogenous Bases: G, C, A, U Pentose Sugar: Ribose Found in all parts of the cell For protein synthesis Less stable than DNA 26 13 FEU Biochemistry Property. All forms of replicatin are prohibited. Seek approval from Ms. Jessa Natividad and Ms. Erika Viloria 8/13/24 RNA Structure Primary Structure Similar to DNA, refers to the single strand nucleotide sequence, written from 5’ to 3’ Secondary Structure Refers to the folding of a single RNA stand Stabilized by hydrogen bonds between complementary bases 27 Types of RNA There are several types of RNA depending on the role that play. There are three main RNA molecules that are involved in the conversion of genetic information into protein products. Messenger RNA (mRNA) Transfer RNA (tRNA) Ribosomal (RNA) (rRNA) 28 14 FEU Biochemistry Property. All forms of replicatin are prohibited. Seek approval from Ms. Jessa Natividad and Ms. Erika Viloria 8/13/24 Types of RNA Messenger RNA (mRNA) – Carries information from DNA inside the nucleus and takes it to ribosomes for protein synthesis – mRNA sequence is used by ribosomes as the basis for the amino acid sequence of proteins 29 Types of RNA Transfer RNA (tRNA) – Delivers amino acids to the sites for protein synthesis – Smallest RNA molecules (75-90 nucleotide units) – ‘clover-leaf’ like structure – L-shaped 3D structure 30 15 FEU Biochemistry Property. All forms of replicatin are prohibited. Seek approval from Ms. Jessa Natividad and Ms. Erika Viloria 8/13/24 Types of RNA Ribosomal RNA (rRNA) – Component of ribosomes – Allows proper binding of mRNA when it enters the ribosome 31 END! 32 16