Premium
Co‐crystal structure of the Fusobacterium ulcerans ZTP riboswitch using an X‐ray free‐electron laser
Author(s) -
Jones Christopher,
Tran Brandon,
Conrad Chelsie,
Stagno Jason,
Trachman Robert,
Fischer Pontus,
Meents Alke,
Ferré-D'Amaré Adrian
Publication year - 2019
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.572
H-Index - 37
ISSN - 2053-230X
DOI - 10.1107/s2053230x19008549
Subject(s) - x ray , physics , optics
Riboswitches are conformationally dynamic RNAs that regulate gene expression by binding specific small molecules. ZTP riboswitches bind the purine‐biosynthetic intermediate 5‐aminoimidazole‐4‐carboxamide riboside 5′‐monophosphate (ZMP) and its triphosphorylated form (ZTP). Ligand binding to this riboswitch ultimately upregulates genes involved in folate and purine metabolism. Using an X‐ray free‐electron laser (XFEL), the room‐temperature structure of the Fusobacterium ulcerans ZTP riboswitch bound to ZMP has now been determined at 4.1 Å resolution. This model, which was refined against a data set from ∼750 diffraction images (each from a single crystal), was found to be consistent with that previously obtained from data collected at 100 K using conventional synchrotron X‐radiation. These experiments demonstrate the feasibility of time‐resolved XFEL experiments to understand how the ZTP riboswitch accommodates cognate ligand binding.