Structural and biophysical characterization of Mycobacterium tuberculosis dodecin Rv1498A

Ultrafast Excited-state Deactivation of Flavins Bound to Dodecin

“…The time constant 3 was somewhat slower for the D 2 O sample ( 3 (D 2 O) 6 Ϯ 2 ps versus 3 (H 2 O) 5 Ϯ 1 ps), and the DADS showed spectral differences, especially around 600 nm. Variation of the starting conditions of the global fit analysis indicate that the time constant 3 is inaccurate, and therefore the results are handled with care. However, global fit analysis indicates that the proton transfer plays a role at least for the faster component ( 2 ).…”

“…However, global fit analysis indicates that the proton transfer plays a role at least for the faster component ( 2 ). The DADS of the time constant 3 shows a significant amplitude at 500 nm and is therefore assigned to the decay of the difference signal at this wavelength. A similar signal is not seen for other flavin-binding proteins (9).…”

“…Riboflavin-binding proteins (RfbPs) 3 have been characterized in eukaryotes as proteins for storage and transport of riboflavin. RfbPs are high affinity binders, and reduce the photochemical reactivity of the highly reactive riboflavins by efficiently quenching light-induced excited states.…”

“…With one ligand per 68 residues, dodecin represents the flavoprotein with highest flavin load known to date. Dodecin has also been found in bacteria where it was characterized as a binder of FMN (2)(3)(4).…”

“…Structures revealed a dodecameric fold, providing six identical binding pockets, which each enables binding of two antiparallel arranged flavins between two tryptophan residues building an aromatic tetrade arrangement ( Fig. 1A) (1)(2)(3)(4)(5)(6)(7).…”