Molecular Biology and Biochemistry of Heme and Copper- containing Dissimilatory Nitrite Reductases

细菌反硝化作用是有机氮返回大气的主要途径。这个过程涉及到一系列的酶和电子供体，它们将硝酸盐还原为分子氮。该奖项的目的是确定两种亚硝酸盐还原酶的结构和功能，这是该系统的关键组成部分。一种是四血红素细胞色素，另一种是非血红素铜蛋白。这两种酶的基因将被克隆。将制备酶的晶体并确定其三维结构。施于土壤的大量氮肥因细菌反硝化作用而流失。这项研究的结果将帮助我们了解这一过程是如何在分子水平上发生的，并可能使我们能够设计出减少反硝化的策略，从而减少肥料径流造成的污染量。

Bacterial denitrification is the major pathway by which organic nitrogen is returned to the atmosphere. The process involves a series of enzymes and electron donors, which reduce nitrate to molecular nitrogen. The objective of this award is to define the structure and function of two nitrite reductases which are key components of the system. One is a tetraheme cytochrome and the other a non-heme copper protein. The genes of the two enzymes will be cloned. Crystals of the enzymes will be prepared and their 3 dimensional structure determined. A tremendous amount of nitrogen fertilizer applied to the soil is lost by bacterial denitrification. Results of this research will help us understand how this process takes place at the molecular level, and may enable us to devise strategies to reduce denitrification and thus cut down the amount of pollution caused by fertilizer run-off.