Article

Purification and characterization of glpX-encoded fructose 1, 6-bisphosphatase, a new enzyme of the glycerol 3-phosphate regulon of Escherichia coli.

Department of Biochemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA.
Journal of Bacteriology (Impact Factor: 2.69). 11/2000; 182(19):5624-7.
Source: PubMed

ABSTRACT In Escherichia coli, gene products of the glp regulon mediate utilization of glycerol and sn-glycerol 3-phosphate. The glpFKX operon encodes glycerol diffusion facilitator, glycerol kinase, and as shown here, a fructose 1,6-bisphosphatase that is distinct from the previously described fbp-encoded enzyme. The purified enzyme was dimeric, dependent on Mn(2+) for activity, and exhibited an apparent K(m) of 35 microM for fructose 1,6-bisphosphate. The enzyme was inhibited by ADP and phosphate and activated by phosphoenolpyruvate.

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    • "Prokaryotic Class I and Class II FBPase are distantly related to each other [13]. Class I contains typical FBPase domain [14], while Class II contains FBPase_glpX domain [15]. When we searched against Pfam database to identify the two kinds of domains in all the available eubacterial F/SBPase whose dual function has been experimentally determined, eight sequences, six of which are from proteobacteria and two from cyanobacteria, were obtained. "
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    BMC Evolutionary Biology 10/2012; 12(1):208. DOI:10.1186/1471-2148-12-208 · 3.41 Impact Factor
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    • "As is the case in Phaeodactylum, one of the T. oceanica FBAs from each compartment (FBA1, FBA2, FBA6) appears to act through metal catalysis (class II) while the second (FBA3, FBA5, FBA4) is predicted to use Schiff-base catalysis (class I) instead. While the metal cofactor of different class II FBAs was found to be Mn2+ [28], Zn2+ [29] or Cd2+ [30] in Escherichia coli, the orthologous FBAs of T. oceanica apparently are differentially regulated through the availability of iron, suggesting the involved metal in these enzymes might be Fe2+, and implying a pairwise substitution by class I enzymes. "
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