Magnesium-induced assembly of a complete DNA polymerase catalytic complex.

摘要: The molecular details of the nucleotidyl transferase reaction have remained speculative, as strategies to trap catalytic intermediates for structure determination utilize substrates lacking primer terminus 3'-OH and Mg2+, resulting in an incomplete distorted active site geometry. Since geometric arrangement these essential atoms will impact chemistry, structural insight into fidelity has been hampered. Here, we present a crystal precatalytic complex DNA polymerase with bound that include Mg2+. This intermediate was trapped nonhydrolyzable deoxynucleotide analog. Comparison two new structures beta or Mg2+ is described. These provide direct evidence both are required achieve proper geometry necessary in-line nucleophilic attack O3' on alphaP incoming nucleotide.