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PubMed · 9880484

One protein, two enzymes.

Y Dai·P C Wensink·R H Abeles
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Abstract

Two enzymes, designated, E-2 and E-2', catalyze different oxidation reactions of an aci-reductone intermediate in the methionine salvage pathway. E-2 and E-2', overproduced in Escherichia coli from the same gene, have the same protein component. E-2 and E-2' are separable on an anion exchange column or a hydrophobic column. Their distinct catalytic and chromatographic properties result from binding different metals. The apo-enzyme, obtained after metal is removed from either enzyme, is catalytically inactive. Addition of Ni2+ or Co2+ to the apo-protein yields E-2 activity. E-2' activity is obtained when Fe2+ is added. Production in intact E. coli of E-2 and E-2' depends on the availability of the corresponding metals. These observations suggest that the metal component dictates reaction specificity.

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Catalytic DomainChromatography, GelChromatography, Ion ExchangeCobaltDioxygenasesElectrophoresis, Polyacrylamide GelEscherichia coliFerrous CompoundsKlebsiella pneumoniaeMethionineMolecular Sequence DataNickelOxygenasesRecombinant ProteinsJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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Y Dai, P C Wensink, R H Abeles. 1999-01-15. One protein, two enzymes.. https://doi.org/10.1074/jbc.274.3.1193

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