Problem 2 To replicate, cells must increase their content of nucleic acids, which requires building blocks including pyrimidines. A key pyrimidine, UMP, is shown below HN. НО-Р-О. OH ОН ОН A. Using the arrow formalism, draw the reaction of UMP with ATP to produce UDP. For convenience, you can draw out only the reactive "triphosphate" portion of ATP (abbreviating adenosine as "Adeno"). B. With the help of an enzyme, uracil can react with phosphoribosylpyrophosphate (PRPP) (below) to form UMP. НО Но HOO HO O ОН Draw PRPP and circle the atom in PRPP where the reaction occurs. What is the hybridization of that atom? C. What is the reaction type? D. Using the PRPP that you drew in Part B, draw a sensible reaction mechanism using the arrow formalism, including the major carbon-containing intermediates (if any) and their relevant resonance forms (if any) (relevant meaning resonance forms related to the reaction mechanism, not in distant parts of the molecule). E. Propose a potential mechanism by which aspartate in the enzyme might facilitate the reaction. A quick drawing is recommended to illustrate your proposal. F. Imagine you try to carry out the above UMP-forming reaction in water without enzyme. Focusing exclusively on reactivity at the PRPP position that you circled in (B) (assuming the rest of the molecule does not react), what is the main product that you would expect? Why?

15th Edition

ISBN:9781337408332

Author:Cecie Starr, Ralph Taggart, Christine Evers, Lisa Starr

Publisher:Cecie Starr, Ralph Taggart, Christine Evers, Lisa Starr

Chapter8: Dna Structure And Function

Section: Chapter Questions

Problem 10SQ: Energy that drives the attachment of a nucleotide to the end of a growing strand of DNA comes from...