Department of Chemistry, Vassar College, 124 Raymond Avenue, Poughkeepsie, NY 12604, USA.
Seattle Structural Genomics Center for Infectious Disease (SSGCID), Seattle, Washington, USA.
Acta Crystallogr F Struct Biol Commun. 2023 Oct 1;79(Pt 10):257-266. doi: 10.1107/S2053230X23008002. Epub 2023 Sep 20.
Inorganic pyrophosphate (PP) is generated as an intermediate or byproduct of many fundamental metabolic pathways, including DNA/RNA synthesis. The intracellular concentration of PP must be regulated as buildup can inhibit many critical cellular processes. Inorganic pyrophosphatases (PPases) hydrolyze PP into two orthophosphates (P), preventing the toxic accumulation of the PP byproduct in cells and making P available for use in biosynthetic pathways. Here, the crystal structure of a family I inorganic pyrophosphatase from Legionella pneumophila is reported at 2.0 Å resolution. L. pneumophila PPase (LpPPase) adopts a homohexameric assembly and shares the oligonucleotide/oligosaccharide-binding (OB) β-barrel core fold common to many other bacterial family I PPases. LpPPase demonstrated hydrolytic activity against a general substrate, with Mg being the preferred metal cofactor for catalysis. Legionnaires' disease is a severe respiratory infection caused primarily by L. pneumophila, and thus increased characterization of the L. pneumophila proteome is of interest.
无机焦磷酸（PP）是许多基本代谢途径（包括 DNA/RNA 合成）的中间产物或副产物。细胞内的 PP 浓度必须受到调控，因为其积累会抑制许多关键的细胞过程。无机焦磷酸酶（PPases）将 PP 水解为两个正磷酸盐（P），防止 PP 副产物在细胞内的毒性积累，并使 P 可用于生物合成途径。本文报道了来自嗜肺军团菌的 I 型无机焦磷酸酶的晶体结构，分辨率为 2.0 Å。嗜肺军团菌 PP 酶（LpPPase）采用同六聚体组装，共享许多其他细菌 I 型 PP 酶共有的寡核苷酸/寡糖结合（OB）β-桶核心折叠。LpPPase 对一般底物表现出水解活性，Mg 是催化的首选金属辅因子。军团病是一种严重的呼吸道感染，主要由嗜肺军团菌引起，因此增加对嗜肺军团菌蛋白质组的描述很有意义。
