title: Thioredoxin 2 from Escherichia coli is not involved in vivo in the recycling process of methionine sulfoxide reductase activities.
abstract: Thioredoxins (Trx) 1 and 2, and three methionine sulfoxide reductases (Msr) whose activities are Trx-dependent, are expressed in Escherichia coli. A metB(1)trxA mutant was shown to be unable to grow on methionine sulfoxide (Met-O) suggesting that Trx2 is not essential in the Msr-recycling process. In the present study, we have determined the kinetic parameters of the recycling process of the three Msrs by Trx2 and the in vivo expression of Trx2 in a metB(1)trxA mutant. The data demonstrate that the lack of growth of the metB(1)trxA mutant on Met-O is due to low in vivo expression of Trx2 and not to the lower catalytic efficiency of Msrs for Trx2.
authors.affiliation: Nancy-Université-Université Henri Poincaré, UMR CNRS-UHP 7214, ARN-RNP, Enzymologie Moléculaire et Structurale, Nancy Université, Faculté des Sciences et Technologies, Vandoeuvre-lès-Nancy, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Jacob
authors.forename: Alexandre
authors.initials: A
authors.lastname: Kriznik
authors.forename: Sandrine
authors.initials: S
authors.lastname: Boschi-Muller
authors.forename: Guy
authors.initials: G
authors.lastname: Branlant
mesh_terms: D004926:Escherichia coli / Q000737:chemistry*; D007700:Kinetics; D051150:Methionine Sulfoxide Reductases / Q000378:metabolism*; D008780:Methyltransferases; D013879:Thioredoxins / Q000378:metabolism*
chemical_list: D013879:Thioredoxins; D051150:Methionine Sulfoxide Reductases; C027219:methionine sulfoxide reductase; D008780:Methyltransferases