Electrospray ionization mass spectrometry analysis of the apo- and metal-substituted forms of the Fur protein.

I. Michaud-Soret (1) , A. Adrait , M. Jaquinod , E. Forest , D. Touati , J. M. Latour

1 LCBM - UMR 5249 - Laboratoire de Chimie et Biologie des Métaux

Fur has been purified and reconstituted with Co2+ and Mn2+. The ESI-MS spectra of the apoprotein as well as Mn-Fur and Co-Fur under acidic denaturating conditions showed the existence of two species of molecular mass 16,660 +/- 3 and 16,792 +/- 3 Da, which correspond, respectively, to the N-terminal methionine 'excised' or 'non-excised' forms of the monomer. This result proves the absence of any other post-translational modification or modification due to metal incorporation. On the other hand, under soft conditions, ESI spectra provided for the first time direct evidence for dimeric metal-containing forms in solution.

Mots clés: ferric uptake; metalloregulator; metal homeostasis

Domaines: Biochimie [q-bio.BM]

I. Michaud-Soret, A. Adrait, M. Jaquinod, E. Forest, D. Touati, et al.. Electrospray ionization mass spectrometry analysis of the apo- and metal-substituted forms of the Fur protein.. FEBS Letters, 1997, 413 (3), pp.473-6. ⟨10.1016/S0014-5793(97)00963-0⟩. ⟨hal-01062972⟩