Specificity of thioredoxins and glutaredoxins as electron donors to two distinct classes of Arabidopsis plastidial methionine sulfoxide reductases B.
Methionine sulfoxide reductases (MSRs) A and B reduce methionine sulfoxide (MetSO) S- and R-diastereomers, respectively, back to Met using electrons generally supplied by thioredoxin. The physiological reductants for MSRBs remain unknown in plants, which display a remarkable variety of thioredoxins (Trxs) and glutaredoxins (Grxs). Using recombinant proteins, we show that Arabidopsis plastidial MSRB1 and MSRB2, which differ regarding the number of presumed redox-active cysteines, possess specific reductants. Most simple-module Trxs, especially Trx m1 and Trx y2, are preferential and efficient electron donors towards MSRB2, while the double-module CDSP32 Trx and Grxs can reduce only MSRB1. This study identifies novel types of reductants, related to Grxs and peculiar Trxs, for MSRB proteins displaying only one redox-active cysteine.
Vieira Dos Santos
Christina
C
CEA, DSV, IBEB, SBVME, Laboratoire d'Ecophysiologie Moléculaire des Plantes (LEMP), UMR 6191, 13108 Saint-Paul-lez-Durance Cedex, France.
Laugier
Edith
E
Tarrago
Lionel
L
Massot
Vincent
V
Issakidis-Bourguet
Emmanuelle
E
Rouhier
Nicolas
N
Rey
Pascal
P
D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D003545:Cysteine / Q000235:genetics / Q000378:metabolism; D004579:Electron Transport; D054477:Glutaredoxins / Q000235:genetics / Q000378:metabolism*; D051150:Methionine Sulfoxide Reductases; D016297:Mutagenesis, Site-Directed; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism*; D018087:Plastids / Q000201:enzymology / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D013379:Substrate Specificity; D013879:Thioredoxins / Q000235:genetics / Q000378:metabolism*; D013997:Time Factors
D029681:Arabidopsis Proteins; D054477:Glutaredoxins; D011994:Recombinant Proteins; D013879:Thioredoxins; D010088:Oxidoreductases; D051150:Methionine Sulfoxide Reductases; C027219:methionine sulfoxide reductase; D003545:Cysteine