Pátek Miroslav, Nesvera Jan, Guyonvarch Armel, Reyes Oscar, Leblon Gérard
Institute of Microbiology, Academy of Sciences of the Czech Republic, Vídenská 1083, CZ-14220 Prague 4, Czech Republic.
J Biotechnol. 2003 Sep 4;104(1-3):311-23. doi: 10.1016/s0168-1656(03)00155-x.
Regulation of gene expression in Corynebacterium glutamicum represents an important issue since this Gram-positive bacterium is a notable industrial amino acid producer. Transcription initiation, beginning by binding of RNA polymerase to the promoter DNA sequence, is one of the main points at which bacterial gene expression is regulated. More than 50 transcriptional promoters have so far been experimentally localized in C. glutamicum. Most of them are assumed to be promoters of vegetative genes recognized by the main sigma factor. Although transcription initiation rate defined by many of these promoters may be affected by transcription factors, which activate or repress their function, the promoter regions share common sequence features, which may be generalized in a consensus sequence. In the consensus C. glutamicum promoter, the prominent feature is a conserved extended -10 region tgngnTA(c/t)aaTgg, while the -35 region is much less conserved. Some commonly utilized heterologous promoters were shown to drive strong gene expression in C. glutamicum. Conversely, some C. glutamicum promoters were found to function in Escherichia coli and in other bacteria. These observations suggest that C. glutamicum promoters functionally conform with the common bacterial promoter scheme, although they differ in some sequence structures.
谷氨酸棒杆菌中的基因表达调控是一个重要问题，因为这种革兰氏阳性细菌是著名的工业氨基酸生产菌。转录起始由RNA聚合酶与启动子DNA序列结合开始，是细菌基因表达调控的主要关键点之一。到目前为止，已经通过实验在谷氨酸棒杆菌中定位了50多个转录启动子。其中大多数被认为是由主要σ因子识别的营养基因的启动子。尽管许多这些启动子定义的转录起始速率可能受到激活或抑制其功能的转录因子的影响，但启动子区域具有共同的序列特征，这些特征可以归纳为一个共有序列。在谷氨酸棒杆菌共有启动子中，突出特征是保守的扩展 -10 区域 tgngnTA(c/t)aaTgg，而 -35 区域的保守性要低得多。一些常用的异源启动子在谷氨酸棒杆菌中显示出驱动强基因表达的能力。相反，一些谷氨酸棒杆菌启动子在大肠杆菌和其他细菌中也能发挥作用。这些观察结果表明，谷氨酸棒杆菌启动子在功能上符合常见的细菌启动子模式，尽管它们在一些序列结构上有所不同。
