1bjk
From Proteopedia
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FERREDOXIN:NADP+ REDUCTASE MUTANT WITH ARG 264 REPLACED BY GLU (R264E)
Overview
Previous studies and the crystal structure of Anabaena PCC 7119 FNR, suggest that the side chains of Arg100 and Arg264 may be directly involved, in the proper NADP+/NADPH orientation for an efficient electron-transfer, reaction. Protein engineering on Arg100 and Arg264 from Anabaena PCC 7119, FNR has been carried out to investigate their roles in complex formation, and electron transfer to NADP+ and to ferredoxin/flavodoxin. Arg100 has, been replaced with an alanine, which removes the positive charge, the long, side chain, as well as the ability to form hydrogen bonds, while a charge, reversal mutation has been made at Arg264 by replacing it with a glutamic, acid. Results with various spectroscopic techniques indicate that the, mutated proteins folded properly and that significant protein structural, rearrangements did not occur. Both mutants have been kinetically, characterized by steady-state as well as fast transient kinetic, techniques, and the three-dimensional structure of Arg264Glu FNR has been, solved. The results reported herein reveal important conceptual, information about the interaction of FNR with its substrates. A critical, role is confirmed for the long, positively charged side chain of Arg100., Studies on the Arg264Glu FNR mutant demonstrate that the Arg264 side chain, is not critical for the nicotinamide orientation or for nicotinamide, interaction with the isoalloxazine FAD moiety. However, this mutant showed, altered behavior in its interaction and electron transfer with its protein, partners, ferredoxin and flavodoxin.
About this Structure
1BJK is a Single protein structure of sequence from Anabaena sp. with SO4 and FAD as ligands. Active as Ferredoxin--NADP(+) reductase, with EC number 1.18.1.2 Full crystallographic information is available from OCA.
Reference
Role of Arg100 and Arg264 from Anabaena PCC 7119 ferredoxin-NADP+ reductase for optimal NADP+ binding and electron transfer., Martinez-Julvez M, Hermoso J, Hurley JK, Mayoral T, Sanz-Aparicio J, Tollin G, Gomez-Moreno C, Medina M, Biochemistry. 1998 Dec 22;37(51):17680-91. PMID:9922134
Page seeded by OCA on Tue Nov 20 11:42:08 2007
