Genome-wide investigation and functional characterization of the beta-ketoadipate pathway in the nitrogen-fixing and root-associated bacterium Pseudomonas stutzeri A1501

文献类型： 外文期刊

第一作者： Li, Danhua

作者： Li, Danhua;Yan, Yongliang;Ping, Shuzhen;Chen, Ming;Zhang, Wei;Li, Liang;Lin, Wenna;Geng, Lizhao;Liu, Wei;Lu, Wei;Lin, Min;Li, Danhua;Lin, Min;Zhang, Wei;Lu, Wei

作者机构：

期刊名称：BMC MICROBIOLOGY （ 影响因子：3.605； 五年影响因子：4.283 ）

ISSN： 1471-2180

年卷期： 2010 年 10 卷

页码：

收录情况： SCI

摘要： Background: Soil microorganisms are mainly responsible for the complete mineralization of aromatic compounds that usually originate from plant products or environmental pollutants. In many cases, structurally diverse aromatic compounds can be converted to a small number of structurally simpler intermediates, which are metabolized to tricarboxylic acid intermediates via the beta-ketoadipate pathway. This strategy provides great metabolic flexibility and contributes to increased adaptation of bacteria to their environment. However, little is known about the evolution and regulation of the beta-ketoadipate pathway in root-associated diazotrophs. Results: In this report, we performed a genome-wide analysis of the benzoate and 4-hydroxybenzoate catabolic pathways of Pseudomonas stutzeri A1501, with a focus on the functional characterization of the beta-ketoadipate pathway. The P. stutzeri A1501 genome contains sets of catabolic genes involved in the peripheral pathways for catabolism of benzoate (ben) and 4-hydroxybenzoate (pob), and in the catechol (cat) and protocatechuate (pca) branches of the beta-ketoadipate pathway. A particular feature of the catabolic gene organization in A1501 is the absence of the catR and pcaK genes encoding a LysR family regulator and 4-hydroxybenzoate permease, respectively. Furthermore, the BenR protein functions as a transcriptional activator of the ben operon, while transcription from the catBC promoter can be activated in response to benzoate. Benzoate degradation is subject to carbon catabolite repression induced by glucose and acetate in A1501. The HPLC analysis of intracellular metabolites indicated that low concentrations of 4-hydroxybenzoate significantly enhance the ability of A1501 to degrade benzoate. Conclusions: The expression of genes encoding proteins involved in the beta-ketoadipate pathway is tightly modulated by both pathway-specific and catabolite repression controls in A1501. This strain provides an ideal model system for further study of the evolution and regulation of aromatic catabolic pathways.

分类号：

  • 相关文献
作者其他论文 更多>>

微信小程序