TY - JOUR
T1 - Catalytic mechanism of hydride transfer between NADP(+)/H and ferredoxin-NADP(+) reductase from Anabaena PCC 7119
AU - Tejero, Jesus
AU - Ramon Peregrina, Jose
AU - Martinez-Julvez, Marta
AU - Gutierrez, Aldo
AU - Gomez-Moreno, Carlos
AU - Scrutton, Nigel S.
AU - Medina, Milagros
PY - 2007/3/1
Y1 - 2007/3/1
N2 - The mechanism of hydride transfer between Anabaena FNR and NADP(+)/H was analysed using for the first time stopped-flow photodiode array detection and global analysis deconvolution. The results indicated that the initial spectral changes, occurring within the instrumental dead time upon reaction of FNR with NADP(+)/H, included not only the initial interaction and complex formation, but also the first subsequent steps of the sequential reactions that involve hydride transfer. Two different charge-transfer complexes formed prior and upon hydride transfer, FNRox-NADPH and FNRrd-NADP(+). Detectable amounts of FNROox-NADPH were found at equilibrium, but FNRrd-NADP(+) accumulated to a small extent and quickly evolved. The spectral properties of both charge-transfer complexes, for the first time in Anabaena FNR, as well as the corresponding inter-conversion hydride transfer rates were obtained. The need of an adequate initial interaction between NADP(+)/H and FNR, and subsequent conformational changes, was also established by studying the reactions of two FNR mutants. (c) 2006 Elsevier Inc. All rights reserved.
AB - The mechanism of hydride transfer between Anabaena FNR and NADP(+)/H was analysed using for the first time stopped-flow photodiode array detection and global analysis deconvolution. The results indicated that the initial spectral changes, occurring within the instrumental dead time upon reaction of FNR with NADP(+)/H, included not only the initial interaction and complex formation, but also the first subsequent steps of the sequential reactions that involve hydride transfer. Two different charge-transfer complexes formed prior and upon hydride transfer, FNRox-NADPH and FNRrd-NADP(+). Detectable amounts of FNROox-NADPH were found at equilibrium, but FNRrd-NADP(+) accumulated to a small extent and quickly evolved. The spectral properties of both charge-transfer complexes, for the first time in Anabaena FNR, as well as the corresponding inter-conversion hydride transfer rates were obtained. The need of an adequate initial interaction between NADP(+)/H and FNR, and subsequent conformational changes, was also established by studying the reactions of two FNR mutants. (c) 2006 Elsevier Inc. All rights reserved.
U2 - 10.1016/j.abb.2006.10.023
DO - 10.1016/j.abb.2006.10.023
M3 - Article
SN - 0003-9861
VL - 459
SP - 79
EP - 90
JO - Archives of Biochemistry and Biophysics
JF - Archives of Biochemistry and Biophysics
IS - 1
ER -