STRUCTURE OF NITRILE REDUCTASE

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 QueF是腈氧化还原酶，其催化修饰的tRNA核苷肌苷的生物合成中的后期步骤。在这些tRNA（包括线粒体tRNA）的反密码子中存在的腺苷与翻译中的基本作用，特别是在调节保真度方面是相容的。在致病性细菌福氏志贺菌（Shigella flexneri）中，喹奥辛生物合成的破坏导致致病性的丧失，使得其生物合成途径中的几种酶成为抗志贺菌病药物的有吸引力的靶标。腈还原酶的结构解决方案已尝试通过分子置换，使用基于相关结构的信息学生成的模型，和MAD，使用浸泡在TaBr衍生物中的晶体。MAD数据是在光束线BL 9 -2上收集的。分子置换不成功。MAD阶段导致部分模型分辨率较低（4 A）。这一模式正在完善之中。

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. QueF is a nitrile oxidoreductase which catalyzes a late step in the biosynthesis of the modified tRNA nucleoside queuosine. The presence of queuosine in the anticodons of these tRNAs (including mitochondrial tRNAs) is compatible with a fundamental role in translation, specifically in modulating fidelity. Disruption of queosine biosynthesis in the pathogenic bacterium Shigella flexneri results in loss of pathogenicity, making several enzymes in its biosynthesis pathway attractive targets for anti-shigellosis drugs. The structure solution of nitrile reductase has been attempted by molecular replacement using an informatics generated model based on a related structure, and MAD using crystals soaked in TaBr derivative. That MAD data were collected on beamline BL9-2. Molecular replacement has been unsuccessful. The MAD phases have resulted in a partial model to low resolution (4 A). Refinement of this model is in progress.