Nucleosides & Nucleotides
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Biomolecules
CHAPTER 3 Biomolecules 3.1 Carbohydrates In the previous chapter you have learnt about the cell and 3.2 Fatty Acids and its organelles. Each organelle has distinct structure and Lipids therefore performs different function. For example, cell membrane is made up of lipids and proteins. Cell wall is 3.3 Amino Acids made up of carbohydrates. Chromosomes are made up of 3.4 Protein Structure protein and nucleic acid, i.e., DNA and ribosomes are made 3.5 Nucleic Acids up of protein and nucleic acids, i.e., RNA. These ingredients of cellular organelles are also called macromolecules or biomolecules. There are four major types of biomolecules— carbohydrates, proteins, lipids and nucleic acids. Apart from being structural entities of the cell, these biomolecules play important functions in cellular processes. In this chapter you will study the structure and functions of these biomolecules. 3.1 CARBOHYDRATES Carbohydrates are one of the most abundant classes of biomolecules in nature and found widely distributed in all life forms. Chemically, they are aldehyde and ketone derivatives of the polyhydric alcohols. Major role of carbohydrates in living organisms is to function as a primary source of energy. These molecules also serve as energy stores, 2021-22 Chapter 3 Carbohydrade Final 30.018.2018.indd 50 11/14/2019 10:11:16 AM 51 BIOMOLECULES metabolic intermediates, and one of the major components of bacterial and plant cell wall. Also, these are part of DNA and RNA, which you will study later in this chapter. The cell walls of bacteria and plants are made up of polymers of carbohydrates. -
Site-Selective Artificial Ribonucleases: Renaissance of Oligonucleotide Conjugates for Irreversible Cleavage of RNA Sequences
molecules Review Site-Selective Artificial Ribonucleases: Renaissance of Oligonucleotide Conjugates for Irreversible Cleavage of RNA Sequences Yaroslav Staroseletz 1,†, Svetlana Gaponova 1,†, Olga Patutina 1, Elena Bichenkova 2 , Bahareh Amirloo 2, Thomas Heyman 2, Daria Chiglintseva 1 and Marina Zenkova 1,* 1 Laboratory of Nucleic Acids Biochemistry, Institute of Chemical Biology and Fundamental Medicine SB RAS, Lavrentiev’s Ave. 8, 630090 Novosibirsk, Russia; [email protected] (Y.S.); [email protected] (S.G.); [email protected] (O.P.); [email protected] (D.C.) 2 School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Oxford Rd., Manchester M13 9PT, UK; [email protected] (E.B.); [email protected] (B.A.); [email protected] (T.H.) * Correspondence: [email protected]; Tel.: +7-383-363-51-60 † These authors contributed equally to this work. Abstract: RNA-targeting therapeutics require highly efficient sequence-specific devices capable of RNA irreversible degradation in vivo. The most developed methods of sequence-specific RNA cleav- age, such as siRNA or antisense oligonucleotides (ASO), are currently based on recruitment of either intracellular multi-protein complexes or enzymes, leaving alternative approaches (e.g., ribozymes Citation: Staroseletz, Y.; Gaponova, and DNAzymes) far behind. Recently, site-selective artificial ribonucleases combining the oligonu- S.; Patutina, O.; Bichenkova, E.; cleotide recognition motifs (or their structural -
Nucleotide Degradation
Nucleotide Degradation Nucleotide Degradation The Digestion Pathway • Ingestion of food always includes nucleic acids. • As you know from BI 421, the low pH of the stomach does not affect the polymer. • In the duodenum, zymogens are converted to nucleases and the nucleotides are converted to nucleosides by non-specific phosphatases or nucleotidases. nucleases • Only the non-ionic nucleosides are taken & phospho- diesterases up in the villi of the small intestine. Duodenum Non-specific phosphatases • In the cell, the first step is the release of nucleosides) the ribose sugar, most effectively done by a non-specific nucleoside phosphorylase to give ribose 1-phosphate (Rib1P) and the free bases. • Most ingested nucleic acids are degraded to Rib1P, purines, and pyrimidines. 1 Nucleotide Degradation: Overview Fate of Nucleic Acids: Once broken down to the nitrogenous bases they are either: Nucleotides 1. Salvaged for recycling into new nucleic acids (most cells; from internal, Pi not ingested, nucleic Nucleosides acids). Purine Nucleoside Pi aD-Rib 1-P (or Rib) 2. Oxidized (primarily in the Phosphorylase & intestine and liver) by first aD-dRib 1-P (or dRib) converting to nucleosides, Bases then to –Uric Acid (purines) –Acetyl-CoA & Purine & Pyrimidine Oxidation succinyl-CoA Salvage Pathway (pyrimidines) The Salvage Pathways are in competition with the de novo biosynthetic pathways, and are both ANABOLISM Nucleotide Degradation Catabolism of Purines Nucleotides: Nucleosides: Bases: 1. Dephosphorylation (via 5’-nucleotidase) 2. Deamination and hydrolysis of ribose lead to production of xanthine. 3. Hypoxanthine and xanthine are then oxidized into uric acid by xanthine oxidase. Spiders and other arachnids lack xanthine oxidase. -
Carbohydrates: Structure and Function
CARBOHYDRATES: STRUCTURE AND FUNCTION Color index: . Very important . Extra Information. “ STOP SAYING I WISH, START SAYING I WILL” 435 Biochemistry Team *هذا العمل ﻻ يغني عن المصدر المذاكرة الرئيسي • The structure of carbohydrates of physiological significance. • The main role of carbohydrates in providing and storing of energy. • The structure and function of glycosaminoglycans. OBJECTIVES: 435 Biochemistry Team extra information that might help you 1-synovial fluid: - It is a viscous, non-Newtonian fluid found in the cavities of synovial joints. - the principal role of synovial fluid is to reduce friction between the articular cartilage of synovial joints during movement O 2- aldehyde = terminal carbonyl group (RCHO) R H 3- ketone = carbonyl group within (inside) the compound (RCOR’) 435 Biochemistry Team the most abundant organic molecules in nature (CH2O)n Carbohydrates Formula *hydrate of carbon* Function 1-provides important part of energy Diseases caused by disorders of in diet . 2-Acts as the storage form of energy carbohydrate metabolism in the body 3-structural component of cell membrane. 1-Diabetesmellitus. 2-Galactosemia. 3-Glycogen storage disease. 4-Lactoseintolerance. 435 Biochemistry Team Classification of carbohydrates monosaccharides disaccharides oligosaccharides polysaccharides simple sugar Two monosaccharides 3-10 sugar units units more than 10 sugar units Joining of 2 monosaccharides No. of carbon atoms Type of carbonyl by O-glycosidic bond: they contain group they contain - Maltose (α-1, 4)= glucose + glucose -Sucrose (α-1,2)= glucose + fructose - Lactose (β-1,4)= glucose+ galactose Homopolysaccharides Heteropolysaccharides Ketone or aldehyde Homo= same type of sugars Hetero= different types Ketose aldose of sugars branched unBranched -Example: - Contains: - Contains: Examples: aldehyde group glycosaminoglycans ketone group. -
1. Nucleotides A. Pentose Sugars – 5-Carbon Sugar 1) Deoxyribose – in DNA 2) Ribose – in RNA B. Phosphate Group C. Nitroge
1. Nucleotides a. Pentose sugars – 5-Carbon sugar 1) Deoxyribose – in DNA 2) Ribose – in RNA b. Phosphate group c. Nitrogenous bases 1) Purines a) Adenine b) Guanine 2) Pyrimidines a) Cytosine b) Thymine 2. Types of Nucleic Acids a. DNA 1) Locations 2) Functions b. RNA 1) Locations 2) Functions E. High Energy Biomolecules 1. Adenosine triphosphate a. Uses 1) Active transport 2) Movement 3) Biosynthesis reactions b. Regeneration 1) ADP + Pi + Energy → ATP 4. Classes of proteins a. Structural – ex. Collagen, keratin b. Transport – Hemoglobin, many β-globulins c. Contractile – Actin and Myosin of muscle tissue d. Regulatory - Hormones e. Immunologic - Antibodies f. Clotting – Thrombin and Fibrin g. Osmotic - Albumin h. Catalytic – Enzymes 1) Characteristics of enzymes • Proteins (most); ribonucleoproteins (few/ribozymes) • Act as organic catalysts • Lower the activation energy of reactions • Not changed by the reaction • Bind to their substrates o Lock-and-key model of enzyme activity o Induced-fit model • Highly specific • Named by adding -ase to substrate name; e.g., maltose/maltase • May require cofactors which may be: o Nonprotein metal ions such as copper, manganese, potassium, sodium o Small organic molecules known as coenzymes. The B vitamins like thiamine (B1) riboflavin (B2) and nicotinamide are precursors of coenzymes. • May require activation; e.g., pepsinogen pepsin in stomach chief cells 4. Factors Affecting Enzyme Action • pH o pepsin (stomach) @ pH = 2; trypsin (small int.) @ pH = 8 • Temperature o Denatured by high temp’s. • Enzyme inhibitors o Competitive inhibitors o Noncompetitive inhibitors • Effect of substrate concentration and reversible reactions and the Law of Mass D. -
Molecular Biology and Applied Genetics
MOLECULAR BIOLOGY AND APPLIED GENETICS FOR Medical Laboratory Technology Students Upgraded Lecture Note Series Mohammed Awole Adem Jimma University MOLECULAR BIOLOGY AND APPLIED GENETICS For Medical Laboratory Technician Students Lecture Note Series Mohammed Awole Adem Upgraded - 2006 In collaboration with The Carter Center (EPHTI) and The Federal Democratic Republic of Ethiopia Ministry of Education and Ministry of Health Jimma University PREFACE The problem faced today in the learning and teaching of Applied Genetics and Molecular Biology for laboratory technologists in universities, colleges andhealth institutions primarily from the unavailability of textbooks that focus on the needs of Ethiopian students. This lecture note has been prepared with the primary aim of alleviating the problems encountered in the teaching of Medical Applied Genetics and Molecular Biology course and in minimizing discrepancies prevailing among the different teaching and training health institutions. It can also be used in teaching any introductory course on medical Applied Genetics and Molecular Biology and as a reference material. This lecture note is specifically designed for medical laboratory technologists, and includes only those areas of molecular cell biology and Applied Genetics relevant to degree-level understanding of modern laboratory technology. Since genetics is prerequisite course to molecular biology, the lecture note starts with Genetics i followed by Molecular Biology. It provides students with molecular background to enable them to understand and critically analyze recent advances in laboratory sciences. Finally, it contains a glossary, which summarizes important terminologies used in the text. Each chapter begins by specific learning objectives and at the end of each chapter review questions are also included. -
Carbohydrates Adapted from Pellar
Carbohydrates Adapted from Pellar OBJECTIVE: To learn about carbohydrates and their reactivities BACKGROUND: Carbohydrates are a major food source, with most dietary guidelines recommending that 45-65% of daily calories come from carbohydrates. Rice, potatoes, bread, pasta and candy are all high in carbohydrates, specifically starches and sugars. These compounds are just a few examples of carbohydrates. Other carbohydrates include fibers such as cellulose and pectins. In addition to serving as the primary source of energy for the body, sugars play a number of other key roles in biological processes, such as forming part of the backbone of DNA structure, affecting cell-to-cell communication, nerve and brain cell function, and some disease pathways. Carbohydrates are defined as polyhydroxy aldehydes or polyhydroxy ketones, or compounds that break down into these substances. They can be categorized according to the number of carbons in the structure and whether a ketone or an aldehyde group is present. Glucose, for example, is an aldohexose because it contains six carbons and an aldehyde functional group. Similarly, fructose would be classified as a ketohexose. glucose fructose A more general classification scheme exists where carbohydrates are broken down into the groups monosaccharides, disaccharides, and polysaccharides. Monosaccharides are often referred to as simple sugars. These compounds cannot be broken down into smaller sugars by acid hydrolysis. Glucose, fructose and ribose are examples of monosaccharides. Monosaccharides exist mostly as cyclic structures containing hemiacetal or hemiketal groups. These structures in solution are in equilibrium with the corresponding open-chain structures bearing aldehyde or ketone functional groups. The chemical linkage of two monosaccharides forms disaccharides. -
Inosine in Biology and Disease
G C A T T A C G G C A T genes Review Inosine in Biology and Disease Sundaramoorthy Srinivasan 1, Adrian Gabriel Torres 1 and Lluís Ribas de Pouplana 1,2,* 1 Institute for Research in Biomedicine, Barcelona Institute of Science and Technology, 08028 Barcelona, Catalonia, Spain; [email protected] (S.S.); [email protected] (A.G.T.) 2 Catalan Institution for Research and Advanced Studies, 08010 Barcelona, Catalonia, Spain * Correspondence: [email protected]; Tel.: +34-934034868; Fax: +34-934034870 Abstract: The nucleoside inosine plays an important role in purine biosynthesis, gene translation, and modulation of the fate of RNAs. The editing of adenosine to inosine is a widespread post- transcriptional modification in transfer RNAs (tRNAs) and messenger RNAs (mRNAs). At the wobble position of tRNA anticodons, inosine profoundly modifies codon recognition, while in mRNA, inosines can modify the sequence of the translated polypeptide or modulate the stability, localization, and splicing of transcripts. Inosine is also found in non-coding and exogenous RNAs, where it plays key structural and functional roles. In addition, molecular inosine is an important secondary metabolite in purine metabolism that also acts as a molecular messenger in cell signaling pathways. Here, we review the functional roles of inosine in biology and their connections to human health. Keywords: inosine; deamination; adenosine deaminase acting on RNAs; RNA modification; translation Citation: Srinivasan, S.; Torres, A.G.; Ribas de Pouplana, L. Inosine in 1. Introduction Biology and Disease. Genes 2021, 12, 600. https://doi.org/10.3390/ Inosine was one of the first nucleobase modifications discovered in nucleic acids, genes12040600 having been identified in 1965 as a component of the first sequenced transfer RNA (tRNA), tRNAAla [1]. -
Multi-Enzymatic Cascades in the Synthesis of Modified Nucleosides
biomolecules Article Multi-Enzymatic Cascades in the Synthesis of Modified Nucleosides: Comparison of the Thermophilic and Mesophilic Pathways Ilja V. Fateev , Maria A. Kostromina, Yuliya A. Abramchik, Barbara Z. Eletskaya , Olga O. Mikheeva, Dmitry D. Lukoshin, Evgeniy A. Zayats , Maria Ya. Berzina, Elena V. Dorofeeva, Alexander S. Paramonov , Alexey L. Kayushin, Irina D. Konstantinova * and Roman S. Esipov Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry RAS, Miklukho-Maklaya 16/10, 117997 GSP, B-437 Moscow, Russia; [email protected] (I.V.F.); [email protected] (M.A.K.); [email protected] (Y.A.A.); [email protected] (B.Z.E.); [email protected] (O.O.M.); [email protected] (D.D.L.); [email protected] (E.A.Z.); [email protected] (M.Y.B.); [email protected] (E.V.D.); [email protected] (A.S.P.); [email protected] (A.L.K.); [email protected] (R.S.E.) * Correspondence: [email protected]; Tel.: +7-905-791-1719 ! Abstract: A comparative study of the possibilities of using ribokinase phosphopentomutase ! nucleoside phosphorylase cascades in the synthesis of modified nucleosides was carried out. Citation: Fateev, I.V.; Kostromina, Recombinant phosphopentomutase from Thermus thermophilus HB27 was obtained for the first time: M.A.; Abramchik, Y.A.; Eletskaya, a strain producing a soluble form of the enzyme was created, and a method for its isolation and B.Z.; Mikheeva, O.O.; Lukoshin, D.D.; chromatographic purification was developed. It was shown that cascade syntheses of modified nu- Zayats, E.A.; Berzina, M.Y..; cleosides can be carried out both by the mesophilic and thermophilic routes from D-pentoses: ribose, Dorofeeva, E.V.; Paramonov, A.S.; 2-deoxyribose, arabinose, xylose, and 2-deoxy-2-fluoroarabinose. -
DNA Stands for Deoxyribose Nucleic Acid
DNA and Protein Synthesis DNA • DNA stands for deoxyribose nucleic acid. • This chemical substance is found in the nucleus of all cells in all living organisms • DNA controls all the chemical changes which take place in cells • The kind of cell which is formed, (muscle, blood, nerve etc) is controlled by DNA Ribose is a sugar, like glucose, but with only five carbon atoms in its molecule. Deoxyribose is almost the same but lacks one oxygen atom. The nitrogen bases are: o ADENINE (A) o THYMINE (T) o CYTOSINE (C) o GUANINE (G) Nucleotides • A molecule of DNA is formed by millions of nucleotides joined together in a long chain. • DNA is a very large molecule made up of a long chain of sub-units. • The sub-units are called nucleotides. • Each nucleotide is made up of a sugar called deoxyribose, a phosphate group -PO4 and an organic (Nitrogen) base: A, T, C, G BASE PAIRING RULE amount of C= amount of G AND amount of A= amount of T • Adenine always pairs with thymine, and guanine always pairs with cytosine. DNA STRUCTURE • The nucleotide bases will point to the inside of the DNA molecule while the outside (backbone) of the DNA molecule will be made of the sugar and phosphate molecules. • When complete the DNA molecule forms a double helix (two spiral sides wrapped together). • The paired strands are coiled into a spiral called A DOUBLE HELIX. Genes • Each chromosome contains hundreds of genes. • Most of your characteristics: hair color, height, how things taste to a person, are determined by the kinds of proteins cells make (gene). -
(12) United States Patent (10) Patent No.: US 8,604,000 B2 De Kort Et Al
USOO8604000B2 (12) United States Patent (10) Patent No.: US 8,604,000 B2 de Kort et al. (45) Date of Patent: Dec. 10, 2013 (54) PALATABLE NUTRITIONAL COMPOSITION 2011/0027391 A1 2/2011 De Kort et al. COMPRISING ANUCLEOTDE AND/ORA 2013, OO12469 A1 1/2013 De Kort et al. NUCLEOSDE AND A TASTE MASKING 2013, OO18012 A1 1/2013 Hageman et al. AGENT FOREIGN PATENT DOCUMENTS (75) Inventors: Esther Jacqueline de Kort, Wageningen EP O 175468 A2 3, 1986 (NL); Martine Groenendijk, EP 1216 041 B1 6, 2002 EP 1282 365 B1 2, 2003 Barendrecht (NL); Patrick Joseph EP 1656 839 A1 5, 2006 Gerardus Hendrikus Kamphuis, EP 1666 092 A2 6, 2006 Utrecht (NL) EP 18OO 675 A1 6, 2007 JP 64-080250 A 3, 1989 (73) Assignee: N.V. Nutricia, Zoetermeer (NL) JP 06-237734. A 8, 1994 JP 10-004918 A 1, 1998 JP 10-136937 A 5, 1998 (*) Notice: Subject to any disclaimer, the term of this JP 11-071274. A 3, 1999 patent is extended or adjusted under 35 WO WO-0038829 A1 T 2000 U.S.C. 154(b) by 213 days. WO WO-01 (32034 A1 5, 2001 WO WO-02/088159 A1 11, 2002 WO WO-02/096464 A1 12/2002 (21) Appl. No.: 12/809,431 WO WO-03 (013276 A1 2, 2003 WO WO-03/041701 A2 5, 2003 (22) PCT Filed: Dec. 22, 2008 WO WO-2005/039597 A2 5, 2005 WO WO-2006/031683 A2 3, 2006 (86). PCT No.: PCT/NL2O08/050843 WO WO-2006,118665 A2 11/2006 WO WO-2006, 127620 A2 11/2006 S371 (c)(1), WO WO-2007/001883 A2 1, 2007 (2), (4) Date: Dec. -
Part 1 in Our Series of Carbohydrate Lectures. in This Section, You Will Learn About Monosaccharide Structure
Welcome to Part 1 in our series of Carbohydrate lectures. In this section, you will learn about monosaccharide structure. The building blocks of larger carbohydrate polymers. 1 First, let’s review why learning about carbohydrates is important. Carbohydrates are used by biological systems as fuels and energy resources. Carbohydrates typically provide quick energy and are one of the primary energy storage forms in animals. Carbohydrates also provide the precursors to other major macromolecules within the body, including the deoxyribose and ribose required for nucleic acid biosynthesis. Carbohydrates can also provide structural support and cushioning/shock absorption, as well as cell‐cell communication, identification, and signaling. 2 Carbohydrates, as their name implies, are water hydrates of carbon, and they all have the same basic core formula (CH2O)n and are always found in the ratio of 1 carbon to 2 hydrogens to 1 oxygen (1:2:1) making them easy to identify from their molecular formula. 3 Carbohydrates can be divided into subcategories based on their complexity. The simplest carbohydrates are the monosaccharides which are the simple sugars required for the biosynthesis of all the other carbohydrate types. Disaccharides consist of two monosaccharides that have been joined together by a covalent bond called the glycosidic bond. Oligosaccharides are polymers that consist of a few monosaccharides covalently linked together, and Polysaccharides are large polymers that contain hundreds to thousands of monosaccharide units all joined together by glycosidic bonds. The remainder of this lecture will focus on monosaccharides 4 Monosaccharides all have alcohol functional groups associated with them. In addition they also have one additional functional group, either an aldehyde or a ketone.