Functional analysis of luxR/luxI in Acidovorax citrulli

文献类型： 外文期刊

第一作者： Wang, T.

作者： Wang, T.;Zhao, T.

作者机构：

关键词： Acidovorax citrulli;QS system;luxI;luxR

期刊名称：CUCURBITACEAE 2012: PROCEEDINGS OF THE XTH EUCARPIA MEETING ON GENETICS AND BREEDING OF CUCURBITACEAE

ISSN：

年卷期： 2012 年

页码：

收录情况： SCI

摘要： Bacterial fruit blotch of melons, caused by Acidovorax citrulli, is a seed borne disease that inflicts serious damages to cucurbit crops worldwide. Like most gram-negative bacteria, the Acidovorax citrulli pathogen has luxR / luxI quorum sensing (QS) system to regulate its biological functions. A method of homologous recombination to construct three mutant allele combinations associated with the QS signal systemic functional genes was employed. The QS system tested contained luxR and luxI single gene deletion mutants and luxR/luxI double gene deletion mutant. The luxR/luxI QS system function was studied by comparing the difference between the wild type and mutant type strains. The results are as follows: (1) Detecting the signaling molecule Acyl homoserine lactones (AHLs): Compared with the wild-type strain, signal substances cannot be detected in luxI and luxR/luxI because of the deletion of luxI, while the luxR could still display a blue chromogenic reaction due to the presence of luxI. This result is consistent with the conclusion that luxI is the gene producing signal substances and luxR is the gene generating the carrier of the signal substances. (2) Pathogenicity determination: the mutant strains displayed reduced virulence, indicating that QS system play an important role in Acidovorax citrulli pathogenicity. (3) Physiology and biochemistry assay: growth ability of mutant lines was: luxR/luxI >luxI>luxR. The Mutant strains increased in adherent ability of biofilm. Thereis no obvious difference in motility ability of extracellular polysaccharide secretion. (4) Real-Time PCR: The expression of five genes related to virulence and two gene including luxI and luxR related to quorum sensing were quantitatively detected by Real-Time PCR. The expression of the seven genes decreased in mutant strains, displaying positive regulation. And the quorum sensing system related gene luxI and luxR were expressed at a lower level in luxR and luxI, respectively. (5) The AHLs of bacterial fruit blotch of melons were extracted, and OHHL (3-oxo-hexanoyl homoserine lactone) was identified quantitatively by liquid chromatography-mass spectrometry (UPLC-MS/MS). The pathogenicity of luxI to melon seedlings was recovered after adding the OHHL.

分类号：

  • 相关文献

[1]XocR, a LuxR solo required for virulence in Xanthomonas oryzae pv. oryzicola. Xu, Huiyong,Zhao, Yancun,Liu, Fengquan,Xu, Huiyong,Qian, Guoliang,Liu, Fengquan,Xu, Huiyong,Qian, Guoliang,Liu, Fengquan. 2015

[2]Effect of chitosan solution on the inhibition of Acidovorax citrulli causing bacterial fruit blotch of watermelon. Li, Bin,Shi, Yu,Shan, Changlin,Zhou, Qing,Ibrahim, Muhammad,Li, Hongye,Xie, Guanlin,Wang, Yanli,Sun, Guochang,Wu, Guoxing. 2013

[3]Genetic diversity analysis of Acidovorax citrulli in China. Yan, Shasha,Yang, Yuwen,Wang, Tielin,Zhao, Tingchang,Schaad, Norman W..

[4]Quorum-sensing contributes to virulence, twitching motility, seed attachment and biofilm formation in the wild type strain Aac-5 of Acidovorax citrulli. Guan, Wei,Yang, Yuwen,Yan, Wanrong,Sun, Baixin,Zhao, Tingchang,Wang, Tielin,Huang, Qi.

[5]Identification of Pathogenicity-Related Genes in Biofilm-Defective Acidovorax citrulli by Transposon Tn5 Mutagenesis. Luo, Jinyan,Chen, Lei,Qiu, Wen,Anjum, Syed Ishtiaq,Yu, Menghao,Shan, Changlin,Li, Bin,Anjum, Syed Ishtiaq,Shan, Changlin,Ilyas, Mehmoona,Wang, Yanli,Sun, Guochang. 2015

[6]Rapid Discrimination between Groups I and II of Acidovorax citrulli Using a Primer Pair Specific to a pilL Gene. Zhong, Jie,Lin, Zhen-Ya,Ma, Ya-Min,Gao, Bi-Da,Liu, Hui-Qin,Zhao, Ting-Chang,Schaad, Norman W..

作者其他论文 更多>>

微信小程序