Single Amino Acid Switch between a Flavin-Dependent Dehalogenase and Nitroreductase
نویسندگان
چکیده
A single mutation within a flavoprotein is capable of switching the catalytic activity of a dehalogenase into a nitroreductase. This change in function correlates with a destabilization of the one-electron-reduced flavin semiquinone that is differentially expressed in the nitro-FMN reductase superfamily during redox cycling. The diversity of function within such a superfamily therefore has the potential to arise from rapid evolution, and its members should provide a convenient basis for developing new catalysts with an altered specificity of choice.
منابع مشابه
Conversion of NfsB, a minor Escherichia coli nitroreductase, to a flavin reductase similar in biochemical properties to FRase I, the major flavin reductase in Vibrio fischeri, by a single amino acid substitution.
NfsB is an oxygen-insensitive nitroreductase of Escherichia coli with significant amino acid sequence homology to the major flavin reductase (FRase I) of Vibrio fischeri. Here, we show that NfsB is convertible to an FRase I-like flavin reductase three times as active as the authentic FRase I by a single amino acid substitution in the least-conserved region.
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