This domain adopts a ribonuclease H-like fold and is structurally related to the C-terminal domain.

1: Structure of the regulatory complex of Escherichia coli IIIGlc with glycerol kinase. Hurley JH, Faber HR, Worthylake D, Meadow ND, Roseman S, Pettigrew DW, Remington SJ; Science. 1993;259:673-677. PMID:8430315

2: Crystal structure of a complex of Escherichia coli glycerol kinase and an allosteric effector fructose 1,6-bisphosphate. Ormo M, Bystrom CE, Remington SJ; Biochemistry 1998;37:16565-16572. PMID:9843423