State Key Laboratory of Agrobiotechnology and College of Biological Sciences, China Agricultural University, Beijing, PR China.
Microbiol Res. 2011 Dec 20;166(8):595-605. doi: 10.1016/j.micres.2010.11.007. Epub 2011 Jan 15.
Our previous study indicated org35 was involved in chemotaxis and interacted with nitrogen fixation transcriptional activator NifA via PAS domain. In order to reveal the role of org35 in nitrogen regulation, the downstream target genes of org35 were identified. We here report differentially expressed genes in org35 mutants comparing with wild type Sp7 by means of cDNA-AFLP. Four up-regulated transcript-derived fragments (TDFs) homologues of chemotaxis transduction proteins were found, including CheW, methyl-accepting chemotaxis protein and response regulator CheY-like receiver. Three distinct TDFs (AB46, AB58 and AB63) were similar to PHB de-polymerase C-terminus, cell shape-determining protein and flagellin domain protein. And 11 TDFs showed similarities with signal transduction proteins, including homologous protein of the nitrogen regulation protein NtrY and nitrate/nitrite response regulator protein NarL. These data suggested that the Azospirillum brasilense org35 was a multi-effecter and involved in chemotaxis, cyst development and regulation of nitrogen fixation.
我们之前的研究表明，org35 参与趋化作用，并通过 PAS 结构域与固氮转录激活因子 NifA 相互作用。为了揭示 org35 在氮调控中的作用，我们鉴定了 org35 突变体与野生型 Sp7 相比的下游靶基因。我们通过 cDNA-AFLP 报告了 org35 突变体中与野生型 Sp7 相比差异表达的基因。发现了 4 个上调的转录物衍生片段（TDF）同源物，这些同源物与趋化转导蛋白有关，包括 CheW、甲基接受趋化蛋白和响应调节子 CheY 样受体。3 个不同的 TDF（AB46、AB58 和 AB63）与 PHB 解聚酶 C 末端、细胞形态决定蛋白和鞭毛域蛋白相似。11 个 TDF 与信号转导蛋白具有相似性，包括氮调控蛋白 NtrY 的同源蛋白和硝酸盐/亚硝酸盐响应调节子 NarL。这些数据表明，巴西固氮螺菌 org35 是一种多效效应物，参与趋化作用、囊泡发育和固氮调节。
