NiFe-Hydrogenases Having an Improved Resistance to Dioxygen, Process for Obtaining Them and Their Applications

摘要

The invention relates to [NiFe]-hydrogenases having an improved resistance to dioxygen, said [NiFe]-hydrogenases may be obtained by:—providing an initial polynucleotide comprising a sequence encoding a large subunit of a [NiFe]-hydrogenase, said large subunit comprising the following peptide motifs: L1: RGXE, wherein X=L, I, F, V or M L2: [R/K]X₁C[G/R]X₂C, wherein Xi is any amino acid residue, X₂=L, V, I or M; L1 and L2 being separated by 16 any amino acid residues; L3: X₁X₂X₃X₄X₅X₆X₇X₈X₉X₁₀X₁₁X₁₂[D/S/E], wherein X₁=D, S, N or E, X₂=H, D, S, N or L, X₅=H, S, A, Q or W, X₆=F, T, Y or G, X₉=L, F, M or Y, the other X_n being any amino acid residue; L4: D[P/I/S]CX₁X₂CX₃X₄[H/R], wherein X₂=A.S.V.G or T, X₁, X₃ and X₄ are any amino acid residue and optionally comprising a motif LO: R[I/V/A]EG[H/D/A].—modifying said initial polynucleotide in order to substitute at least one of the residues X₂ of motif L2 and Z or X₄ of motif L3 and Z or X₉ of motif L3 of said large subunit by a methionine.