The soluble pyocins S2 and S4 from Pseudomonas aeruginosa bind to the same FpvAI receptor.
The soluble pyocins S2 and S4 from Pseudomonas aeruginosa bind to the same FpvAI receptor.
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DOI：
10.1002/mbo3.27
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发表时间：
2012-09
期刊：
影响因子：
3.4
通讯作者：
Cornelis, Pierre
中科院分区：
文献类型：
--
作者：
Elfarash, Ameer;Wei, Qing;Cornelis, Pierre
可溶性(S型)绿脓菌素是铜绿假单胞菌细菌素，它通过特定的受体进入杀死非免疫性铜绿假单胞菌细胞，在绿脓菌素S2的情况下，该受体是铁载体吡喃佛定受体FpvA1，在绿脓菌素S3的情况下，是FpvAII。铜绿假单胞菌PAO_1基因组4327697-4327359位的核苷酸序列尚未注释，但根据对其基因组序列的分析，推测该序列编码的是位于PA3866侧翼的脓毒菌素S4基因的免疫基因。利用RT-PCR检测免疫基因的表达，证实存在与S4腐蛋白基因重叠的免疫基因。克隆了编码Pyocin S4的PA3866基因和编码免疫蛋白的下游基因，并在大肠杆菌中进行了表达，获得了His标记的S4 Pyocin。对43株铜绿假单胞菌进行了聚合酶链式反应(PCR)分型，以确定它们的铁吡啶受体基因(fpvAI-III)，并检测了它们对腐霉素S4的敏感性。所有对S4敏感的菌株均具有I型铁吡啶受体fpvA基因。检测到一些S4抗性的I型fpvA阳性菌株，但它们都具有S4免疫基因，并在免疫基因缺失后成为S4敏感株。在一株对S4敏感的菌株中，fpvAI受体基因被缺失，不出所料，突变株对S4产生了抗药性。利用FpvAI受体进入细胞，将其N-末端受体结合区(RBD)克隆到pET-15b载体中，并在大肠杆菌中表达。当纯化的RBD与Pyocin S4以不同的比例混合时，观察到抑制杀伤作用，表明S2RBD与Pyocin S4竞争与FpvAI受体的结合。S2RBD也被证明增强了PvdA pyoverdine基因的表达，这表明它和pyoverdine一样，是通过已知的铁载体介导的信号传递途径发挥作用的。
Soluble (S-type) pyocins are Pseudomonas aeruginosa bacteriocins that kill nonimmune P. aeruginosa cells by gaining entry via a specific receptor, which, in the case of pyocin S2, is the siderophore pyoverdine receptor FpvAI, and in the case of pyocin S3, FpvAII. The nucleic acid sequence at the positions 4327697–4327359 of P. aeruginosa PAO1 genome was not annotated, but it was predicted to encode the immunity gene of the flanking pyocin S4 gene (PA3866) based on our analysis of the genome sequence. Using RT-PCR, the expression of the immunity gene was detected, confirming the existence of an immunity gene overlapping the S4 pyocin gene. The PA3866 coding for pyocin S4 and the downstream gene coding for the immunity protein were cloned and expressed in Escherichia coli and the His-tagged S4 pyocin was obtained in pure form. Forty-three P. aeruginosa strains were typed via PCR to identify their ferripyoverdine receptor gene (fpvAI–III) and were tested for their sensitivity to pyocin S4. All S4-sensitive strains had the type I ferripyoverdine receptor fpvA gene. Some S4-resistant type I fpvA-positive strains were detected, but all of them had the S4 immunity gene, and, following the deletion of the immunity gene, became S4-sensitive. The fpvAI receptor gene was deleted in a S4-sensitive strain, and, as expected, the mutant became resistant to S4. The N-terminal receptor binding domain (RBD) of pyocin S2, which also uses the FpvAI receptor to enter the cell, was cloned in the pET-15b vector, and expressed in E. coli. When the purified RBD was mixed with pyocin S4 at different ratios, an inhibition of killing was observed, indicating that S2 RBD competes with the pyocin S4 for the binding to the FpvAI receptor. The S2 RBD was also shown to enhance the expression of the pvdA pyoverdine gene, suggesting that it, like pyoverdine, works via the known siderophore-mediated signalization pathway.
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影响因子：
3.9
作者：
Riley, MA;Wertz, JE
通讯作者：
Wertz, JE
影响因子：
3.2
作者：
Baysse, C;Meyer, JM;Cornelis, P
通讯作者：
Cornelis, P
DOI：
10.1073/pnas.76.4.1648
发表时间：
1979-01-01
影响因子：
11.1
作者：
FIGURSKI, DH;HELINSKI, DR
通讯作者：
HELINSKI, DR
影响因子：
3.2
作者：
Leoni, L;Ciervo, A;Visca, P
通讯作者：
Visca, P
影响因子：
2.8
作者：
Ghysels, B;Dieu, BTM;Cornelis, P
通讯作者：
Cornelis, P