Interdomain Flexibility within NADPH Oxidase Suggested by SANS Using LMNG Stealth Carrier
Department
Molecular and Cellular Biology
Document Type
Article
Publication Date
8-4-2020
Abstract
Small angle neutron scattering (SANS) provides a method to obtain important low-resolution information for integral membrane proteins (IMPs), challenging targets for structural determination. Specific deuteration furnishes a "stealth" carrier for the solubilized IMP. We used SANS to determine a structural envelope of SpNOX, the Streptococcus pneumoniae NADPH oxidase (NOX), a prokaryotic model system for exploring structure and function of eukaryotic NOXes. SpNOX was solubilized in the detergent lauryl maltose neopentyl glycol, which provides optimal SpNOX stability and activity. Using deuterated solvent and protein, the lauryl maltose neopentyl glycol was experimentally undetected in SANS. This affords a cost-effective SANS approach for obtaining novel structural information on IMPs. Combining SANS data with molecular modeling provided a first, to our knowledge, structural characterization of an entire NOX enzyme. It revealed a distinctly less compact structure than that predicted from the docking of homologous crystal structures of the separate transmembrane and dehydrogenase domains, consistent with a flexible linker connecting the two domains.
Journal Title
Biophysical journal
Volume
119
Issue
3
First Page
605
Last Page
618
Digital Object Identifier (DOI)
10.1016/j.bpj.2020.06.025