Diacylglycerol (DAG) is a second messenger that acts as a protein kinase C activator. The catalytic domain is assumed from the finding of bacterial homologues. YegS is the Escherichia coli protein in this family whose crystal structure reveals an active site in the inter-domain cleft formed by four conserved sequence motifs, revealing a novel metal-binding site. The residues of this site are conserved across the family [5].

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2: Molecular cloning of a novel diacylglycerol kinase isozyme with a pleckstrin homology domain and a C-terminal tail similar to those of the EPH family of protein-tyrosine kinases. Sakane F, Imai S, Kai M, Wada I, Kanoh H; J Biol Chem 1996;271:8394-8401. PMID:8626538

3: Purification, cDNA-cloning and expression of human diacylglycerol kinase. Schaap D, de Widt J, van der Wal J, Vandekerckhove J, van Damme J, Gussow D, Ploegh HL, van Blitterswijk WJ, van der Bend RL; FEBS Lett 1990;275:151-158. PMID:2175712

4: Diacylglycerol kinase: a key modulator of signal transduction? Kanoh H, Yamada K, Sakane F; Trends Biochem Sci 1990;15:47-50. PMID:2159661

5: Crystal structure of YegS, a homologue to the mammalian diacylglycerol kinases, reveals a novel regulatory metal binding site. Bakali HM, Herman MD, Johnson KA, Kelly AA, Wieslander A, Hallberg BM, Nordlund P; J Biol Chem. 2007;282:19644-19652. PMID:17351295