Hm. Hoard et al., Microelectrospray ionization analysis of noncovalent interactions within the electron transferring flavoprotein, BIOC BIOP R, 282(1), 2001, pp. 297-305
Citations number
22
Categorie Soggetti
Biochemistry & Biophysics
Journal title
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
Cofactor associations within the electron transferring flavoprotein (ETF) w
ere studied in real time using microelectrospray ionization-mass spectromet
ry (mu ESI-MS). Initial analysis of porcine (pETF) and human ETF (hETF) rev
ealed only the holoprotein. When mu ESI-MS source energies were increased,
both pETF and hETF readily lost AMP. Analysis of hETF and pETF in methanol
revealed intact alpha- and beta -subunits, and beta -subunit with AMP. The
pETF also contained beta -subunit with FAD and beta -subunit with both cofa
ctors. In contrast to crystal structure predictions, AMP dissociates more r
eadily than FAD, and the pETF beta -subunit has an intimate association wit
h FAD. This work demonstrates the complementarity of mu ESI-MS with NMR X-r
ay and optical spectroscopy in the analysis of noncovalent complexes. (C) 2
001 Academic Press.