Structural changes of oxygen-sensing transcription factor revealed through anoxic small-angle X-ray scattering
Year: 2022
Type: article
Abstract: The facultative anaerobe Escherichia coli transitions between aerobic and anaerobic metabolism using an oxygensensing transcription factor, known as Fumarate and Nitrate Reduction (FNR) regulator protein. The presence or absence of molecular oxygen is communicated through an Fe-S cluster, such that FNR dimerization and DNA binding occur only when oxygen is not abundant in the cell. Until now, this structural change had not been directly observed. Anoxic (<30 ppm oxygen) small angle X-ray scattering (anSAXS) techniques were developed at the Cornell High Energy Synchrotron Source (CHESS) ID-7A to provide the first structural evidence of the dependence on anaerobic conditions for the dimeric form to bind DNA and to demonstrate oxygen-induced dissociation from dimer to monomer in E. coli FNR. This novel experimental setup combines anaerobic technique with chromatography-coupled SAXS, opening new opportunities for the study of highly oxygen-sensitive metalloenzymes with medical and environmental importance.
Institution: Cornell University
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W4295920263