Francisco Velazquez - Academia.edu (original) (raw)
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Papers by Francisco Velazquez
Research in Microbiology, 2007
The normal role of the phosphoenolpyruvateecarbohydrate phosphotransferase system (PTS) is phosph... more The normal role of the phosphoenolpyruvateecarbohydrate phosphotransferase system (PTS) is phosphorylation and subsequent uptake of specific sugars. However, analysis of the distribution of PTS proteins in 206 genomes covering major bacterial groups indicates that the conventional function of PTS proteins as devices for carbohydrate phosphorylation and transport is an exception found in Enterobacteriacea, Vibrionales and Firmicutes, rather than a rule for all bacteria. Instead, available evidence suggests that a core set of C-responsive phosphotransferases have been evolutionarily drafted towards diversity of regulatory functions in response inter alia to the global economy of the C and N pools.
Journal of Bacteriology, 2001
An investigation was made into the role of the ptsO gene in carbon source inhibition of the Pu pr... more An investigation was made into the role of the ptsO gene in carbon source inhibition of the Pu promoter belonging to the Pseudomonas putida upper TOL (toluene degradation) operon. ptsO is coexpressed with ptsN , the loss of which is known to render Pu unresponsive to glucose. Both ptsN and ptsO , coding for the phosphoenolpyruvate:sugar phosphotransferase system (PTS) family proteins IIA Ntr and NPr, respectively, have been mapped adjacent to the rpoN gene of P. putida . The roles of these two genes in the responses of Pu to glucose were monitored by lacZ reporter technology with a P. putida strain engineered with all regulatory elements in monocopy gene dosage. In cells lacking ptsO , Pu activity seemed to be inhibited even in the absence of glucose. A functional relationship with ptsN was revealed by the phenotype of a double ptsN ptsO mutant that was equivalent to the phenotype of a mutant with a single ptsN disruption. Moreover, phosphorylation of the product of ptsO seemed to b...
Research in Microbiology, 2007
The normal role of the phosphoenolpyruvateecarbohydrate phosphotransferase system (PTS) is phosph... more The normal role of the phosphoenolpyruvateecarbohydrate phosphotransferase system (PTS) is phosphorylation and subsequent uptake of specific sugars. However, analysis of the distribution of PTS proteins in 206 genomes covering major bacterial groups indicates that the conventional function of PTS proteins as devices for carbohydrate phosphorylation and transport is an exception found in Enterobacteriacea, Vibrionales and Firmicutes, rather than a rule for all bacteria. Instead, available evidence suggests that a core set of C-responsive phosphotransferases have been evolutionarily drafted towards diversity of regulatory functions in response inter alia to the global economy of the C and N pools.
Journal of Bacteriology, 2001
An investigation was made into the role of the ptsO gene in carbon source inhibition of the Pu pr... more An investigation was made into the role of the ptsO gene in carbon source inhibition of the Pu promoter belonging to the Pseudomonas putida upper TOL (toluene degradation) operon. ptsO is coexpressed with ptsN , the loss of which is known to render Pu unresponsive to glucose. Both ptsN and ptsO , coding for the phosphoenolpyruvate:sugar phosphotransferase system (PTS) family proteins IIA Ntr and NPr, respectively, have been mapped adjacent to the rpoN gene of P. putida . The roles of these two genes in the responses of Pu to glucose were monitored by lacZ reporter technology with a P. putida strain engineered with all regulatory elements in monocopy gene dosage. In cells lacking ptsO , Pu activity seemed to be inhibited even in the absence of glucose. A functional relationship with ptsN was revealed by the phenotype of a double ptsN ptsO mutant that was equivalent to the phenotype of a mutant with a single ptsN disruption. Moreover, phosphorylation of the product of ptsO seemed to b...