Abstract
Six mutants (Y26A, C27S, Y29F, Y29P, C30S and Y26W/Y29P) have been engineered in order to explore the active site of poplar glutaredoxin (Grx) (Y26CPYC30). The cysteinic mutants indicate that Cys 27 is the primary nucleophile. Phe is a good substitute for Tyr 29, but the Y29P mutant was inactive. The Y26A mutation caused a moderate loss of activity. The YCPPC and WCPPC mutations did not improve the reactivity of Grx with the chloroplastic NADP-malate dehydrogenase, a well known target of thioredoxins (Trxs). The results are discussed in relation with the known biochemical properties of Grx and Trx.
MeSH terms
-
Amino Acid Sequence
-
Amino Acids, Aromatic / genetics
-
Amino Acids, Aromatic / metabolism
-
Binding Sites
-
Dehydroascorbic Acid / metabolism
-
Dehydroascorbic Acid / pharmacology
-
Disulfides / metabolism
-
Enzyme Activation
-
Ethanol / analogs & derivatives*
-
Ethanol / metabolism
-
Glutaredoxins
-
Magnoliopsida* / genetics
-
Magnoliopsida* / metabolism
-
Malate Dehydrogenase / metabolism
-
Mutagenesis, Site-Directed / genetics*
-
NADP / metabolism
-
Oxidation-Reduction
-
Oxidoreductases*
-
Plant Proteins / chemistry
-
Plant Proteins / genetics
-
Plant Proteins / metabolism
-
Proteins / chemistry*
-
Proteins / genetics*
-
Proteins / metabolism
-
Trees / genetics
-
Trees / metabolism
-
Tyrosine / metabolism
Substances
-
Amino Acids, Aromatic
-
Disulfides
-
Glutaredoxins
-
Plant Proteins
-
Proteins
-
Ethanol
-
Tyrosine
-
2-hydroxyethyl disulfide
-
NADP
-
Oxidoreductases
-
Malate Dehydrogenase
-
Dehydroascorbic Acid