Goswami Anwesha, Liu Xiaodong, Cai Wenlong, Wyche Thomas P, Bugni Tim S, Meurillon Maïa, Peyrottes Suzanne, Perigaud Christian, Nonaka Koichi, Rohr Jürgen, Van Lanen Steven G
Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY, USA.
Department of Pharmaceutical Sciences, University of Wisconsin-Madison, WI, USA.
FEBS Lett. 2017 Feb;591(3):468-478. doi: 10.1002/1873-3468.12554. Epub 2017 Jan 25.
LipL and Cpr19 are nonheme, mononuclear Fe(II)-dependent, α-ketoglutarate (αKG):UMP oxygenases that catalyze the formation of CO , succinate, phosphate, and uridine-5'-aldehyde, the last of which is a biosynthetic precursor for several nucleoside antibiotics that inhibit bacterial translocase I (MraY). To better understand the chemistry underlying this unusual oxidative dephosphorylation and establish a mechanistic framework for LipL and Cpr19, we report herein the synthesis of two biochemical probes-[1',3',4',5',5'- H]UMP and the phosphonate derivative of UMP-and their activity with both enzymes. The results are consistent with a reaction coordinate that proceeds through the loss of one H atom of [1',3',4',5',5'- H]UMP and stereospecific hydroxylation geminal to the phosphoester to form a cryptic intermediate, (5'R)-5'-hydroxy-UMP. Thus, these enzyme catalysts can additionally be assigned as UMP hydroxylase-phospholyases.
LipL和Cpr19是不含血红素的单核铁（II）依赖性α-酮戊二酸（αKG）：UMP氧化酶，可催化生成CO、琥珀酸、磷酸盐和尿苷-5'-醛，其中最后一种是几种抑制细菌转位酶I（MraY）的核苷抗生素的生物合成前体。为了更好地理解这种不寻常的氧化去磷酸化背后的化学过程，并为LipL和Cpr19建立一个机制框架，我们在此报告了两种生化探针——[1',3',4',5',5'-H]UMP和UMP的膦酸酯衍生物——的合成及其与这两种酶的活性。结果与反应坐标一致，该坐标通过[1',3',4',5',5'-H]UMP的一个氢原子的损失以及与磷酸酯偕位的立体特异性羟基化形成一个隐蔽中间体（5'R）-5'-羟基-UMP。因此，这些酶催化剂还可被指定为UMP羟化酶-磷酸裂解酶。
