Assignments of 19F NMR resonances and exploration of dynamics in a long-chain flavodoxin

Taylor A Varner; Nishya Mohamed-Raseek; Anne-Frances Miller

doi:10.1016/j.abb.2021.108839

Assignments of ¹⁹F NMR resonances and exploration of dynamics in a long-chain flavodoxin

Arch Biochem Biophys. 2021 May 30:703:108839. doi: 10.1016/j.abb.2021.108839. Epub 2021 Mar 13.

Authors

Taylor A Varner¹, Nishya Mohamed-Raseek¹, Anne-Frances Miller²

Affiliations

¹ Department of Chemistry, University of Kentucky, Lexington, KY, 40506, USA.
² Department of Chemistry, University of Kentucky, Lexington, KY, 40506, USA. Electronic address: afmill3r2@gmail.com.

PMID: 33727041
DOI: 10.1016/j.abb.2021.108839

Abstract

Flavodoxin is a small protein that employs a non-covalently bound flavin to mediate single-electron transfer at low potentials. The long-chain flavodoxins possess a long surface loop that is proposed to interact with partner proteins. We have incorporated ¹⁹F-labeled tyrosine in long-chain flavodoxin from Rhodopseudomonas palustris to gain a probe of possible loop dynamics, exploiting the presence of a Tyr in the long loop in addition to Tyr residues near the flavin. We report ¹⁹F resonance assignments for all four Tyrs, and demonstration of a pair of resonances in slow exchange, both corresponding to a Tyr adjacent to the flavin. We also provide evidence for dynamics affecting the Tyr in the long loop. Thus, we show that ¹⁹F NMR of ¹⁹F-Tyr labeled flavodoxin holds promise for monitoring possible changes in conformation upon binding to partner proteins.

Keywords: (19)F NMR; Fluoro-tyrosine; Long-chain flavodoxin; Partner protein interactions; Protein dynamics.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Flavodoxin / chemistry*
Flavodoxin / metabolism*
Models, Molecular
Nuclear Magnetic Resonance, Biomolecular*
Protein Conformation

Substances

Flavodoxin