Adipocytes lack glycerol kinase so they cannot metabolize the glycerol produced during triacyl glycerol degradation. This glycerol is instead shuttled to the liver via the blood where it is:
Phosphorylated by glycerol kinase to glycerol 3-phosphate.
Glycerol Kinase (alternative name, ATP:glycerol 3-phosphotransferase or Glycerokinase) adopts a ribonuclease H-like fold consisting of an alpha-beta 2-layer sandwich of CATH family 3.30.420.40. As of March 2010[update], there were 20 structures of this protein in the PDB, most of which are homodimeric.