Disruption of tonB in Bordetella bronchiseptica and Bordetella pertussis prevents utilization of ferric siderophores, haemin and haemoglobin as iron sources.
Disruption of tonB in Bordetella bronchiseptica and Bordetella pertussis prevents utilization of ferric siderophores, haemin and haemoglobin as iron sources.
复制标题
支气管败血博德特氏菌和百日咳博德特氏菌中 tonB 的破坏会阻碍铁铁载体、血红素和血红蛋白作为铁源的利用。
DOI：
10.1099/00221287-145-9-2453
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发表时间：
1999
期刊：
影响因子：
1.5
通讯作者：
B. Beall
中科院分区：
文献类型：
--
作者：
M. Nicholson;B. Beall
通过检测与已知tonB蛋白的Pro-Glu和Pro-Lys重复序列对应的两个退化寡核苷酸杂交的染色体限制性内切片段，克隆了bronchiseptica tonB基因。tonB（Bb）基因位于exbB和exbD同源物的上游，位于fur调控启动子的下游。杂交结果表明，tonB操纵子及其侧翼区域在支气管结核杆菌、百日咳杆菌和副百日咳杆菌之间高度保守。bronchiseptica中tonB的破坏导致其无法在限铁培养基中生长，并且无法利用碱性蛋白、肠杆菌蛋白、铬铁、去铁胺B、血红蛋白和血红蛋白。虽然在临床百日咳分离物中不可能灭活tonB，但在实验室百日咳菌株中，tonB被破坏，该菌株先前被选择用于在Luria-Bertani培养基上生长。百日咳白喉杆菌突变体与支气管结核杆菌突变体具有相似的铁复合物利用缺陷表型。存在于质粒上的支气管结核杆菌tonB操纵子不能与大肠杆菌tonB突变体互补，但在一个fepA突变体中观察到肠杆菌蛋白利用的低效重构，该突变体含有百日咳结核菌fepA同源物和tonB（Bb）操纵子的质粒拷贝。
The Bordetella bronchiseptica tonB gene was cloned by detection of a chromosomal restriction fragment hybridizing with each of two degenerate oligonucleotides that corresponded to Pro-Glu and Pro-Lys repeats characteristic of known TonB proteins. The tonB(Bb) gene was situated upstream of exbB and exbD homologues and downstream of a putative Fur-regulated promoter. Hybridization results indicated that the tonB operon and flanking regions were highly conserved between B. bronchiseptica, Bordetella pertussis and Bordetella parapertussis. Disruption of tonB in B. bronchiseptica resulted in inability to grow in iron-limiting media, and inability to utilize alcaligin, enterobactin, ferrichrome, desferroxamine B, haemin and haemoglobin. Although it was not possible to inactivate tonB in a clinical B. pertussis isolate, tonB was disrupted in a laboratory B. pertussis strain previously selected for the ability to grow on Luria-Bertani medium. This B. pertussis tonB mutant shared a similar iron complex utilization deficient phenotype with the B. bronchiseptica tonB mutant. The B. bronchiseptica tonB operon present on a plasmid did not complement an Escherichia coli tonB mutant, but inefficient reconstitution of enterobactin utilization was observed in one fepA mutant harbouring plasmid copies of the B. pertussis fepA homologue and tonB(Bb) operon.