DNA Structure and Replication PDF
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This document details the chemistry of nucleic acids, focusing on the forces that determine the structure of macromolecules. Topics covered include covalent bonds, non-covalent bonds, and the hydrophobic effect, providing insights into DNA structure.
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21/10/2024, 11:20 DNA Structure and Replication DNA Structure and Replication Course BS1030 Lesson Date October 15, 2024 Type...
21/10/2024, 11:20 DNA Structure and Replication DNA Structure and Replication Course BS1030 Lesson Date October 15, 2024 Type Lecture flashcards Empty Add a property R Add a comment… CHEMISTRY OF NUCLEIC ACIDS FORCES THAT DETERMINE MACROMOLECULAR STRUCTURE Covalent bonds - very strong single & double Short (C–C = 1.54Å) Shared electrons 85-175 kcal / mol Non-covalent bonds Electro static interactions: Weak to strong c. 1–50 kcal / mol Depend on distance Depend on dielectric constant “Salt bridge” Hydrogen bonds: Weak 1–5 kcal / mol Longer than covalent bonds c. 2Å Directional Donor ----- Acceptor Van der Waals interactions: https://www.notion.so/DNA-Structure-and-Replication-1114017e9763809d8964f0050fdeac9d 1/5 21/10/2024, 11:20 DNA Structure and Replication Weak 0.5–1 kcal / mol Attraction between induced partial charges The Hydrophobic Effect Disorder is more “favourable” than Order - Entropy Normally water is very disordered Water becomes ordered on “hydrophobic” surfaces This is unfavourable Hence it is favourable to bury hydrophobic surfaces so they don’t make water ordered DNA 4 x nitrogenous bases 5 carbon neutral sugar phosphate PHOSPHATES at ph 7 - protons are not on the phosphate SUGARS https://www.notion.so/DNA-Structure-and-Replication-1114017e9763809d8964f0050fdeac9d 2/5 21/10/2024, 11:20 DNA Structure and Replication 4 carbon ring - not planar C2 lacks an oxygen BASES Purine - adenine and guanine Pyrimidine - cytosine, thymine (DNA) uracil (RNA) https://www.notion.so/DNA-Structure-and-Replication-1114017e9763809d8964f0050fdeac9d 3/5 21/10/2024, 11:20 DNA Structure and Replication NUCLEOSIDE - RNA b-glycosidic bond N---C BASES: adenosine guanosine cytidine thymidine uridine https://www.notion.so/DNA-Structure-and-Replication-1114017e9763809d8964f0050fdeac9d 4/5 21/10/2024, 11:20 DNA Structure and Replication DNA 5’-MonoPhosphate deoxyAdenosine dAMP 3’ - 5’ phosphodiester links phosphate now only have one charge - less acidic https://www.notion.so/DNA-Structure-and-Replication-1114017e9763809d8964f0050fdeac9d 5/5
