Global gene expression during stringent response in Corynebacterium glutamicum in presence and absence of the rel gene encoding (p)ppGpp synthase.
Global gene expression during stringent response in Corynebacterium glutamicum in presence and absence of the rel gene encoding (p)ppGpp synthase.
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DOI：
10.1186/1471-2164-7-230
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发表时间：
2006-09-08
期刊：
影响因子：
4.4
通讯作者：
Kalinowski J
中科院分区：
文献类型：
--
作者：
Brockmann-Gretza O;Kalinowski J
严格反应是微生物对营养胁迫的初始反应。在严格响应期间，小核苷酸（p）ppGpp充当全局调节剂并重编程细菌转录。在这项工作中，严格的反应控制的遗传网络的特点是在氨基酸生产谷氨酸棒杆菌。对一个C.利用基因芯片技术，对不能合成（p）ppGpp和不能诱导严格反应的谷氨酸（glutamicum）rel基因缺失突变株与其rel基因完全缺失的亲本菌株进行了比较。共发现357个基因在rel缺陷突变株中差异转录。在第二个实验中，通过在早期指数生长期添加DL-丝氨酸异羟肟酸盐（SHX）诱导严格响应。使用组氨酸和丝氨酸生物合成基因通过实时RT-PCR确定对转录的最大效应的时间点。所有这些基因的转录在加入SHX后10分钟达到最大值。进行微阵列实验，比较rel-proficient菌株和rel突变体的SHX诱导培养物的转录组。将差异表达基因分为三类。A类包括仅在完整rel基因存在下差异调节的基因。这类基因包括非必需σ因子基因sigB，其被上调，以及大量参与氮代谢的基因被下调。B类包括在两种菌株中响应于SHX而差异调节的基因，其独立于rel基因。大量编码核糖体蛋白的基因都属于这一类，它们都被下调。C类包含仅在rel突变体中响应于SHX而差异调节的基因。这一类包括编码推定的应激蛋白和全球转录调节因子的基因，这些基因可能负责与其rel-proficient亲本菌株直接比较时在rel突变体中检测到的复杂转录模式。In C.谷氨酸的严格响应在转录组水平上对诱导的氨基酸饥饿进行快速应答。与大肠杆菌和枯草芽孢杆菌的转录反应也有明显的差异。值得注意的是氮代谢基因的rel依赖性调节和编码核糖体蛋白的基因的rel非依赖性调节。
The stringent response is the initial reaction of microorganisms to nutritional stress. During stringent response the small nucleotides (p)ppGpp act as global regulators and reprogram bacterial transcription. In this work, the genetic network controlled by the stringent response was characterized in the amino acid-producing Corynebacterium glutamicum. The transcriptome of a C. glutamicum rel gene deletion mutant, unable to synthesize (p)ppGpp and to induce the stringent response, was compared with that of its rel-proficient parent strain by microarray analysis. A total of 357 genes were found to be transcribed differentially in the rel-deficient mutant strain. In a second experiment, the stringent response was induced by addition of DL-serine hydroxamate (SHX) in early exponential growth phase. The time point of the maximal effect on transcription was determined by real-time RT-PCR using the histidine and serine biosynthetic genes. Transcription of all of these genes reached a maximum at 10 minutes after SHX addition. Microarray experiments were performed comparing the transcriptomes of SHX-induced cultures of the rel-proficient strain and the rel mutant. The differentially expressed genes were grouped into three classes. Class A comprises genes which are differentially regulated only in the presence of an intact rel gene. This class includes the non-essential sigma factor gene sigB which was upregulated and a large number of genes involved in nitrogen metabolism which were downregulated. Class B comprises genes which were differentially regulated in response to SHX in both strains, independent of the rel gene. A large number of genes encoding ribosomal proteins fall into this class, all being downregulated. Class C comprises genes which were differentially regulated in response to SHX only in the rel mutant. This class includes genes encoding putative stress proteins and global transcriptional regulators that might be responsible for the complex transcriptional patterns detected in the rel mutant when compared directly with its rel-proficient parent strain. In C. glutamicum the stringent response enfolds a fast answer to an induced amino acid starvation on the transcriptome level. It also showed some significant differences to the transcriptional reactions occuring in Escherichia coli and Bacillus subtilis. Notable are the rel-dependent regulation of the nitrogen metabolism genes and the rel-independent regulation of the genes encoding ribosomal proteins.
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影响因子：
4.8
作者：
Dukan, S;Nyström, T
通讯作者：
Nyström, T
影响因子：
3.2
作者：
Beckers, G;Bendt, AK;Burkovski, A
通讯作者：
Burkovski, A
DOI：
10.1007/bf00268530
发表时间：
1976-01-01
期刊：
MOLECULAR AND GENERAL GENETICS
影响因子：
--
作者：
BLUMENTHAL, RM;LEMAUX, PG;DENNIS, PP
通讯作者：
DENNIS, PP
影响因子：
3.6
作者：
BORMANN, ER;EIKMANNS, BJ;SAHM, H
通讯作者：
SAHM, H
影响因子：
2.1
作者：
Halgasova, N;Bukovska, G;Kormanec, J
通讯作者：
Kormanec, J