Strictly polyphosphate-dependent glucokinase in a polyphosphate-accumulating bacterium, Microlunatus phosphovorus

ATP-dependent glucokinase is suggested to have evolved from a hypothetical polyphosphate (polyP)-dependent glucokinase (polyP-GK) via a bifunctional polyP/ATP glucokinase (polyP/ATP-GK). Here we showed that polyP-GK is present in a polyP-accumulating bacterium, Microlunatus phosphovorus. The polyP-GK produced glucose-6-P-i from glucose and polyP, but it could not phosphorylate glucose with ATP. The polyP-GK was most closely related to the polyP/ATP-GK of Mycobacterium tuberculosis.