Key enzyme in the regulation of glycerol uptake and metabolism. Catalyzes the phosphorylation of glycerol to yield sn-glycerol 3-phosphate. It also catalyzes the phosphorylation of dihydroxyacetone, L-glyceraldehyde and D-glyceraldehyde. It uses only ATP. ATP + glycerol = ADP + H(+) + sn-glycerol 3-phosphate Activity of this regulatory enzyme is affected by several metabolites. The non-competitive allosteric inhibition by fructose 1,6-bisphosphate (FBP) causes alterations in the quaternary structure of the enzyme. FBP inhibition requires that the enzyme exists only in a tetrameric state. Salt such as KCl reduces the affinity of the tetrameric form of the enzyme for FBP. Unphosphorylated phosphocarrier protein EIIA-Glc (III-Glc), an integral component of the bacterial phosphotransferase (PTS) system, also inhibits non-competitively and allosterically the activity. Unlike FBP, both the dimer and the tetramer appear to be fully sensitive to enzyme EIIA-Glc inhibition. Zn(+2) greatly enhances the inhibitory potency of EIIA-Glc. Both allosteric regulatory agents are strongly pH dependent, with maximal inhibition occurring at pH 6.5. Optimum pH is 9.8. Polyol metabolism; glycerol degradation via glycerol kinase pathway; sn-glycerol 3-phosphate from glycerol: step 1/1. Homotetramer and homodimer (in equilibrium). Heterodimer with EIIA-Glc (crr). Binds 1 zinc ion per glycerol kinase EIIA-Glc dimer. The zinc ion is important for dimerization. By L-alpha-glycerol 3-phosphate. Belongs to the FGGY kinase family.