首页> 外文期刊>Infection and immunity >Characterization of the cciIR Quorum-Sensing System in Burkholderia cenocepacia
【24h】

Characterization of the cciIR Quorum-Sensing System in Burkholderia cenocepacia

机译:洋葱伯克霍尔德菌中cciIR群体感应系统的表征

获取原文
           

摘要

Several transmissible Burkholderia cenocepacia strains that infect multiple cystic fibrosis patients contain a genomic island designated as the cenocepacia island (cci). The cci contains a predicted N-acylhomoserine lactone (AHL) synthase gene, cciI, and a predicted response regulator gene, cciR. AHL production profiles indicated that CciI catalyzes the synthesis of N-hexanoyl-l-homoserine lactone and minor amounts of N-octanoyl-l-homoserine lactone. The cciI and cciR genes were found to be cotranscribed by reverse transcription-PCR analysis, and the expression of a cciIR::luxCDABE fusion in a cciR mutant suggested that the cciIR system negatively regulates its own expression. B. cenocepacia strains also have a cepIR quorum-sensing system. Expression of cepI::luxCDABE or cepR::luxCDABE fusions in a cciR mutant showed that CciR negatively regulates cepI but does not regulate cepR. Expression of the cciIR::luxCDABE fusion in a cepR mutant indicated that functional CepR is required for cciIR expression. Phylogenetic analysis suggested that the cciIR system was acquired by horizontal gene transfer from a distantly related organism and subsequently incorporated into the ancestral cepIR regulatory network. Mutations in cciI, cciR, cepI cciI, and cepR cciR were constructed in B. cenocepacia K56-2. The cciI mutant had greater protease activity and less swarming motility than the parent strain. The cciR mutant had less protease activity than the parent strain. The phenotypes of the cepI cciI and cepR cciR mutants were similar to cepI or cepR mutants, with less protease activity and swarming motility than the parent strain.
机译:感染多发性囊性纤维化患者的几种可传播的伯克霍尔德菌新菌菌株含有一个称为 c eno c epacia i sland(cci)。该cci包含一个预测的 N-酰基高丝氨酸内酯(AHL)合酶基因 cciI 和一个预测的响应调节基因 cciR。 AHL的生产概况指出CciI催化 N -己酰基-1-高丝氨酸内酯和少量的 N-辛酰基-1-高丝氨酸内酯的合成。通过逆转录-PCR分析发现 cciI cciR 基因是共转录的, cciIR :: luxCDABE的表达 cciR 突变体中的融合表明 cciIR 系统会对自身的表达产生负调控。 B。 cenocepacia 菌株也具有 cepIR 群体感应系统。 cepI :: luxCDABE cepR :: luxCDABE 融合蛋白在 cciR 中的表达突变体表明CciR负调控 cepI ,但不调控 cepR。 cciIR :: luxCDABE 融合蛋白的表达一个 cepR 突变体表明 cciIR 表达需要功能性的CepR。系统发育分析表明, cciIR 系统是通过水平基因转移从一个远缘的生物中获得的,随后被整合到祖先的 cepIR 调控网络中。在 B中构建了 cciI cciR cepI cciI cepR cciR 中的突变。 cenocepacia K56-2。与亲本菌株相比, cciI 突变体具有更高的蛋白酶活性和更小的群体运动能力。 cciR 突变体的蛋白酶活性低于亲本菌株。 cepI cciI cepR cciR 突变体的表型与 cepI cepR 突变体相似,但蛋白酶活性较低和成群的运动能力比亲本菌株高。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号