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Title: Reduction Midpoint Potentials of Bifurcating Electron Transfer Flavoproteins
Recently, a variety of enzymes have been found to accept electrons from NAD(P)H yet reduce lower-potential carriers such as ferredoxin and flavodoxin semiquinone, in apparent violation of thermodynamics. The reaction is favorable overall, however, because these enzymes couple the foregoing endergonic one-electron transfer to exergonic transfer of the other electron from each NAD(P)H, in a process called 'flavin-based electron bifurcation'. The reduction midpoint potentials (E°s) of the multiple flavins in these enzymes are critical to their mechanisms. We describe methods we have found to be useful for measuring each of the E°s of each of the flavins in bifurcating electron transfer flavoproteins.
Authors:
; ; ;
Award ID(s):
1808433
Publication Date:
NSF-PAR ID:
10157399
Journal Name:
Methods in enzymology
ISSN:
0076-6879
Sponsoring Org:
National Science Foundation
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