The inducible trimethylamine N-oxide reductase of Escherichia coli K12: its localization and inducers.
We used an anti-trimethylamine-N-oxide reductase (EC 1.6.6.9) serum and different immunological techniques (Ouchterlony, rocket immunoelectrophoresis, immunoblotting) to show that dimethylsulphoxide (DMSO), tetrahydrothiophene 1-oxide (THTO) and pyridine N-oxide (PNO) were effective inducers of the inducible form of trimethylamine N-oxide reductase. We confirmed this genetically and biochemically using a strain in which phage MudII 1734 carrying lacZ was inserted into torA, the structural gene for inducible trimethylamine-N-oxide reductase. By subcellular fractionation and quantitation with rocket immunoelectrophoresis, we showed that the enzyme was principally localized in the periplasmic fraction. Constitutive trimethylamine-N-oxide reductase was localized in the membrane fraction and, like the inducible enzyme showed a broad specificity with respect to various compounds such as DMSO, THTO and PNO. Apart from their immunological properties, the two enzymes could be clearly differentiated by their temperature stability.
Silvestro
A
A
Centre National de la Recherche Scientifique, Département de Biologie, Faculté des Sciences de Luminy, Marseille, France.
Pommier
J
J
Pascal
M C
MC
Giordano
G
G
D000693:Anaerobiosis; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D004790:Enzyme Induction; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D005838:Genotype; D007106:Immune Sera; D005779:Immunodiffusion; D007122:Immunoelectrophoresis; D007700:Kinetics; D046911:Macromolecular Substances; D008744:Methylamines / Q000494:pharmacology; D009247:NADH, NADPH Oxidoreductases / Q000096:biosynthesis* / Q000302:isolation & purification / Q000378:metabolism; D000587:Oxidoreductases Acting on CH-NH Group Donors; D011725:Pyridines / Q000494:pharmacology
D007106:Immune Sera; D046911:Macromolecular Substances; D008744:Methylamines; D011725:Pyridines; C013229:pyridine N-oxide; C021567:methylamine dehydrogenase; D000587:Oxidoreductases Acting on CH-NH Group Donors; D009247:NADH, NADPH Oxidoreductases; C005855:trimethyloxamine; D004121:Dimethyl Sulfoxide