Expanded role for the nitrogen assimilation control protein in the response of Klebsiella pneumoniae to nitrogen stress.
Expanded role for the nitrogen assimilation control protein in the response of Klebsiella pneumoniae to nitrogen stress.
复制标题
氮同化控制蛋白在肺炎克雷伯菌对氮胁迫反应中的作用扩大。
DOI：
10.1128/jb.00931-09
复制
发表时间：
2010
影响因子：
3.2
通讯作者：
Bender,RobertA
中科院分区：
文献类型：
--
作者：
Frisch,RyanL;Bender,RobertA
Klebsiella pneumoniaeis able to utilize many nitrogen sources, and the utilization of some of these nitrogen sources is dependent on the nitrogen assimilation control (NAC) protein. Seven NAC-regulated promoters have been characterized inK. pneumoniae, and nine NAC-regulated promoters have been found by microarray analysis inEscherichia coli. So far, all characterized NAC-regulated promoters have been directly related to nitrogen metabolism. We have used a genome-wide analysis of NAC binding under nitrogen limitation to identify the regions of the chromosome associated with NAC inK. pneumoniae. We found NAC associated with 99 unique regions of the chromosome under nitrogen limitation.In vitro, 84 of the 99 regions associate strongly enough with purified NAC to produce a shifted band by electrophoretic mobility shift assay. Primer extension analysis of the mRNA from genes associated with 17 of the fragments demonstrated that at least one gene associated with each fragment was NAC regulated under nitrogen limitation. The large size of the NAC regulon inK. pneumoniaeindicates that NAC plays a larger role in the nitrogen stress response than it does inE. coli. Although a majority of the genes with identifiable functions that associated with NAC under nitrogen limitation are involved in nitrogen metabolism, smaller subsets are associated with carbon and energy acquisition (18 genes), and growth rate control (10 genes). This suggests an expanded role for NAC regulation during the nitrogen stress response, where NAC not only regulates genes involved in nitrogen metabolism but also regulates genes involved in balancing carbon and nitrogen pools and growth rate.
