Question

If you substituted the hydrogen atoms on the methylene moiety of the dUMP intermediate (indicated by an asterisk) for a deuterium, what kind of isotope effect would you observe. H2N H2folate H2N Inverse secondary KIE HN CH2 H HN a. HN CH2 b. Normal secondary KIE он 0 0 H c. Inverse primary KIE d. Normal primary KIE CH HN 146 "О-Р-О 0 "О-Р-О- Cys146 он dTMP Он

Answer 1

Answer is a or Inverse secondary KIE.as the hybridization of the asterisk carbon increases from sp2 to sp3 and it is not directly involved in bond breaking.