Catalyzes the reversible conversion of 2-phosphoglycerate into phosphoenolpyruvate. It is essential for the degradation of carbohydrates via glycolysis. It is also a component of the RNA degradosome, a multi-enzyme complex involved in RNA processing and messenger RNA degradation. Its interaction with RNase E is important for the turnover of mRNA, in particular on transcripts encoding enzymes of energy-generating metabolic routes. Its presence in the degradosome is required for the response to excess phosphosugar. May play a regulatory role in the degradation of specific RNAs, such as ptsG mRNA, therefore linking cellular metabolic status with post-translational gene regulation.