pubmed:abstractText |
During anaerobic growth on L-fucose, Escherichia coli excretes L-1,2-propanediol formed by an inducible NAD-linked oxidoreductase. The activity of this enzyme is highly induced by L-fucose only anaerobically. However, in strains bearing a hybrid operon with the promoter of fucO (the propanediol oxidoreductase gene) fused to lacZYA, the beta-galactosidase activity is inducible by fucose both anaerobically and aerobically. In merodiploids bearing both fucO+ and phi(fucO-lac), propanediol oxidoreductase is inducible only anaerobically, but beta-galactosidase remains inducible both aerobically and anaerobically. Thus, the absence of respiratory control in the expression of phi(fucO-lac) cannot be attributed to a polarity effect of the fusion on a gene encoding a protein with autogenous regulatory function in transcription. The respiratory effect on the induced propanediol oxidoreductase activity is therefore post-transcriptional.
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pubmed:publicationType |
Journal Article,
Comparative Study,
Research Support, U.S. Gov't, P.H.S.,
Research Support, U.S. Gov't, Non-P.H.S.
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