Fructose and mannose metabolism in Aeromonas hydrophila: identification of transport systems and catabolic pathways.
Aeromonas hydrophila was examined for fructose and mannose transport systems. A. hydrophila was shown to possess a phosphoenolpyruvate (PEP): fructose phosphotransferase system (fructose-PTS) and a mannose-specific PTS, both induced by fructose and mannose. The mannose-PTS of A. hydrophila exhibited cross-reactivity with Escherichia coli mannose-PTS proteins. The fructose-PTS proteins exhibited cross-reactivities with E. coli and Xanthomonas campestris fructose-PTS proteins. In A. hydrophila grown on mannose as well as on fructose, the phosphorylated derivative accumulated from fructose was fructose 1-phosphate. Identification of fructose 1-phosphate was confirmed by 13C-NMR spectroscopy. 1-Phosphofructokinase (1-PFK), which converts the product of the PTS reaction to fructose 1,6-diphosphate, was present in A. hydrophila grown with fructose but not on mannose. An inducible phosphofructomutase (PFM) activity, an unusual enzyme converting fructose 1-phosphate to fructose 6-phosphate, was detected in extracts induced by mannose or fructose. These results suggest that in cells grown on fructose, fructose 1-phosphate could be converted to fructose 1,6-diphosphate either directly by the 1-PFK activity or via fructose 6-phosphate by the PFM and 6-phosphofructokinase activities. In cells grown on mannose, the degradation of fructose 1-phosphate via PFM and the Embden-Meyerhof pathway appeared to be a unique route.
Binet
Marie R B
MRB
Unité des Entérobactéries, Institut National de la Santé et de la Recherche U389, Institut Pasteur, 75724 Paris cedex 15, France.
Rager
Marie-Noelle
MN
Service de Résonance Magnétique Nucléaire, URA 403, Ecole Nationale Supérieure de Chimie de Paris, 75231 Paris cedex 05, France.
Bouvet
Odile M M
OMM
Unité des Entérobactéries, Institut National de la Santé et de la Recherche U389, Institut Pasteur, 75724 Paris cedex 15, France.
D016980:Aeromonas hydrophila / Q000378:metabolism*; D001692:Biological Transport; D005632:Fructose / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D008358:Mannose / Q000378:metabolism*; D010766:Phosphorylation
D005632:Fructose; D008358:Mannose