HYDROXYPROPYLPHOSPHONIC ACID EPOXIDASE (HPPE) BOUND WITH SUBSTRATE ANALOGS

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 抗生素磷霉素的生物合成途径很耐人寻味，因为它创造了一种具有碳-磷键的天然产物，并利用了酶的反应，其反应在生物学上是前所未有的。为了研究这一不寻常的途径，并探索最终生物合成酶hppE催化的独特环氧化反应，我们先前获得了四种X射线结构：分辨率为2.0？的脱辅酶；分辨率为2.4？的天然Fe(II)结合形式；分辨率为1.8？的tris-(hydroxymethyl)aminomethane-Co(II)-enzyme络合物结构；以及分辨率为2.5？的底物-钴(II)-酶络合物结构。我们目前的研究旨在进一步阐明利用与HppE结合的底物和底物类似物来合成磷霉素的区域特异性和立体特异性机制。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The biosynthetic pathway of the antibiotic fosfomycin is intriguing in that it creates a natural product with a carbon-phosphorus bond and utilizes enzymes whose reactions have no precedent in biology. To investigate this unusual pathway and to probe the unique epoxidation reaction catalyzed by the final biosynthetic enzyme, HppE from Streptomyces wedmorensis, we previously obtained four X-ray structures: the apoenzyme at 2.0 ¿ resolution; a native Fe(II)-bound form at 2.4 ¿ resolution; a tris-(hydroxymethyl)aminomethane-Co(II)-enzyme complex structure at 1.8 ¿ resolution, and a substrate-Co(II)-enzyme complex structure at 2.5 ¿ resolution (in press). Our current studies aim to further elucidate the regiospecific and stereospecific mechanism of fosfomycin biosynthesis using substrates and substrate analogs bound to HppE.