TY - JOUR
T1 - Incorporation of molybdenum in rubredoxin
T2 - models for mononuclear molybdenum enzymes
AU - Maiti, Biplab Kumar
AU - Maia, Luisa B.
AU - Silveira, Célia Marisa Costa Figueiredo
AU - Todorovic, Smilja
AU - Carreira, Cintia
AU - Carepo, Marta S. P.
AU - Grazina, Raquel
AU - Moura, Isabel
AU - Pauleta, Sofia R.
AU - Moura, Jose J. G.
N1 - Sem PDF.
We acknowledge Fundacao para a Ciencia e Tecnologia (FCT) for the financial support Granted to REQUIMTE (PEst-C/EQB/LA0006/2013) and UCIBIO-REQUIMTE (UID/Multi/04378/2013), BKM (SFRH/BPD/63066/2009) and SRP (FCT-ANR/BBB-MET0023/2012). NMR data were collected on 400-MHz spectrometer that is part of the National NMR Network, also supported by FCT (RECI/BBB-BQB/0230/2012).
PY - 2015/7
Y1 - 2015/7
N2 - Molybdenum is found in the active site of enzymes usually coordinated by one or two pyranopterin molecules. Here, we mimic an enzyme with a mononuclear molybdenum-bis pyranopterin center by incorporating molybdenum in rubredoxin. In the molybdenum-substituted rubredoxin, the metal ion is coordinated by four sulfurs from conserved cysteine residues of the apo-rubredoxin and two other exogenous ligands, oxygen and thiol, forming a Mo-(VI)-(S-Cys)(4)(O)(X) complex, where X represents -OH or -SR. The rubredoxin molybdenum center is stabilized in a Mo(VI) oxidation state, but can be reduced to Mo(IV) via Mo(V) by dithionite, being a suitable model for the spectroscopic properties of resting and reduced forms of molybdenum-bis pyranopterin-containing enzymes. Preliminary experiments indicate that the molybdenum site built in rubredoxin can promote oxo transfer reactions, as exemplified with the oxidation of arsenite to arsenate.
AB - Molybdenum is found in the active site of enzymes usually coordinated by one or two pyranopterin molecules. Here, we mimic an enzyme with a mononuclear molybdenum-bis pyranopterin center by incorporating molybdenum in rubredoxin. In the molybdenum-substituted rubredoxin, the metal ion is coordinated by four sulfurs from conserved cysteine residues of the apo-rubredoxin and two other exogenous ligands, oxygen and thiol, forming a Mo-(VI)-(S-Cys)(4)(O)(X) complex, where X represents -OH or -SR. The rubredoxin molybdenum center is stabilized in a Mo(VI) oxidation state, but can be reduced to Mo(IV) via Mo(V) by dithionite, being a suitable model for the spectroscopic properties of resting and reduced forms of molybdenum-bis pyranopterin-containing enzymes. Preliminary experiments indicate that the molybdenum site built in rubredoxin can promote oxo transfer reactions, as exemplified with the oxidation of arsenite to arsenate.
KW - Metal-substituted rubredoxin
KW - Models of molybdenum-containing enzymes
KW - Resonance Raman
KW - F-19-NMR
KW - DMSO reductase family
KW - RESONANCE RAMAN CHARACTERIZATION
KW - NICKEL-SUBSTITUTED RUBREDOXIN
KW - PERIPLASMIC NITRATE REDUCTASE
KW - NONHEME IRON PROTEIN
KW - DESULFOVIBRIO-GIGAS
KW - SULFITE OXIDASE
KW - ARSENITE OXIDASE
KW - CLOSTRIDIUM-PASTEURIANUM
KW - ALCALIGENES-FAECALIS
KW - OXIDATION-REDUCTION
U2 - 10.1007/s00775-015-1268-0
DO - 10.1007/s00775-015-1268-0
M3 - Article
C2 - 25948393
SN - 0949-8257
VL - 20
SP - 821
EP - 829
JO - JBIC Journal of Biological Inorganic Chemistry
JF - JBIC Journal of Biological Inorganic Chemistry
IS - 5
ER -