tRNA and DNA bases undergo extensive modification to form novel nucleotides that are crucial in numerous physiological functions. The biosynthesis pathways for the three 7-deazaguanine modifications archaeosine (G+), preQ<sub>0</sub> and queuosine (Q) are well documented, however the structures of key biosynthesis enzymes remain unknown. Crystallization of three of these enzymes was attempted over the course of 8 weeks. GAT-QueC catalyzes the final step in the biosynthesis of G+ in the D-loops of archaeal tRNAs and stabilizes their structures. DpdA is a DNA guanine transglycosylase that installs PreQ<sub>0</sub> in bacterial DNA as part of a restriction-modification bacterial defense system. DUF2419 is a putative nucleoside hydrolase involved in human salvage of Q from gut microflora, a process necessary for the biosynthesis of neurotransmitters. Initial crystals of GAT-QueC and DpdA were successfully grown using the vapor diffusion method. Further study will aim to mass-produce and harvest these crystals for structural analysis.

Crystallization of three enzymes involved in the modification of tRNA and DNA with 7-deazaguanines

Macromolecular Chemistry: The Second Century

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ACS Spring 2020 National Meeting & Expo

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.