Mayaro virus infection alters glucose metabolism in cultured cells through activation of the enzyme 6-phosphofructo 1-kinase.

Departamento de Bioquímica Medica, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
Molecular and Cellular Biochemistry (Impact Factor: 2.39). 12/2004; 266(1-2):191-8. DOI: 10.1023/B:MCBI.0000049154.17866.00
Source: PubMed

ABSTRACT Although it is well established that cellular transformation with tumor virus leads to changes on glucose metabolism, the effects of cell infection by non-transforming virus are far to be completely elucidated. In this study, we report the first evidence that cultured Vero cells infected with the alphavirus Mayaro show several alterations on glucose metabolism. Infected cells presented a two fold increase on glucose consumption, accompanied by an increment in lactate production. This increase in glycolytic flux was also demonstrated by a significant increase on the activity of 6-phosphofructo 1-kinase, one of the regulatory enzymes of glycolysis. Analysis of the kinetic parameters revealed that the regulation of 6-phosphofructo 1-kinase is altered in infected cells, presenting an increase in Vmax along with a decrease in Km for fructose-6-phosphate. Another fact contributing to an increase in enzyme activity was the decrease in ATP levels observed in infected cells. Additionally, the levels of fructose 2,6-bisphosphate, a potent activator of this enzyme, was significantly reduced in infected cells. These observations suggest that the increase in PFK activity may be a compensatory cellular response to the viral-induced metabolic alterations that could lead to an impairment of the glycolytic flux and energy production.

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