Increased pyruvate orthophosphate dikinase activity results in an alternative gluconeogenic pathway in Rhizobium (Sinorhizobium) meliloti

The formation of phosphoenolpyruvate (PEP) is a major step in the gluconeogenic pathway in which tricarboxylic acid (TCA) cycle intermediates are converted to hexose sugars. In Rhizobium (now Sinorhizobium) meliloti this step is catalysed by the enzyme PEP carboxykinase (PCK) which converts oxaloacetate to PEP. R. meliloti Pck- mutants grow very poorly with TCA cycle intermediates as the sole source of carbon. Here, the isolation and mapping of …