The bifunctional undecaprenol kinase/phosphatase (UdpK) is a small, prokaryotic, integral membrane kinase, homologous with Escherichia coli diacylglycerol kinase and expressed by the dgkA gene. In Gram-positive bacteria, UdpK is involved in the homeostasis of the bacterial undecaprenoid pool, where it converts undecaprenol to undecaprenyl phosphate (C₅₅P) and also catalyses the reverse process. C₅₅P is the universal lipid carrier and critical to numerous glycopolymer and glycoprotein biosynthetic pathways in bacteria. DgkA gene expression has been linked to facilitating bacterial growth and survival in response to environmental stressors, as well being implicated as a resistance mechanism to the topical antibiotic bacitracin, by providing an additional route to C₅₅P. Therefore, identification of UdpK inhibitors could lead to novel antibiotic treatments. A combination of homology modelling and mutagenesis experiments on UdpK have been used to identify residues that may be involved in kinase/phosphatase activity. In this review, we will summarise recent work on the mechanism and substrate specificity of UdpK.

双功能十一碳烯醇激酶/磷酸酶（UdpK）是一种小的，原核的整合膜激酶，与大肠杆菌二酰基甘油激酶同源，并由dgkA基因表达。在革兰氏阳性细菌中，UdpK参与细菌十一碳二烯类化合物池的稳态，在其中它将十一碳烯醇转化为十一碳烯酸磷酸酯（C ₅₅ P），并催化逆过程。C ₅₅ P是通用脂质载体，对细菌中众多糖聚合物和糖蛋白生物合成途径至关重要。k基因表达已与促进细菌生长和对环境胁迫的应答有关，并通过提供另一种对C ₅₅ P的途径而被认为是对局部抗生素杆菌肽的耐药机制。因此，鉴定UdpK抑制剂可导致新型抗生素治疗。UdpK的同源性建模和诱变实验相结合已用于鉴定可能与激酶/磷酸酶活性有关的残基。在这篇综述中，我们将总结有关UdpK的机制和底物特异性的最新研究。