SELENATE REDUCTASE: A MOLYBDENUM-CONTAINING ENZYME FROM THAUERA SELENATIS

本子项目是利用由NIH/NCRR资助的中心赠款提供的资源的众多研究子项目之一。子项目和研究者（PI）可能已经从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。列出的机构是中心的，不一定是研究者的机构。硒酸盐在某些生境中是一种丰富的氧阴离子，特别是在含硒土壤的农业排水中。能够将硒酸盐还原为亚硒酸盐和较难溶元素硒的生物体是生物修复的潜在介质。一种能够做到这一点的生物是硒化梭菌，它利用硒酸还原酶。它是一种周质酶，由三个异源亚基组成，分别为100kda、37kda和23kda。每摩尔酶含有1mol钼，12mol铁和8mol酸不稳定硫。本课题旨在利用多波长异常色散（MAD）技术解决硒酸还原酶的结构问题。将收集有关铁吸收边的x射线衍射数据和用于确定相的异常差异。

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. Selenate is an abundant oxyanion in some habitats, particularly in agricultural drainage waters from seleniferous soils. Organisms capable of reducing selenate to selenite and the less soluble elemental selenium are of interest as potential mediators of bioremediation. One organism capable of this is Thauera selenatis, using the enzyme selenate reductase. It is a periplasmic enzyme, consisting of three heterologous subunits at 100 kDa, 37 kDa and 23 kDa. It contains 1 mole of molybdenum, 12 moles of iron and 8 moles of acid-labile sulfur per mole of enzyme. This project aims to solve the structure of selenate reductase by the technique of multiple wavelength anomalous dispersion (MAD). X-ray diffraction data will be collected about the iron absorption edge and the anomalous differences used to determine phases.