Siderophore-mediated iron acquisition from transferrin by Pseudomonas aeruginosa.
Siderophore-mediated iron acquisition from transferrin by Pseudomonas aeruginosa.
复制标题
铜绿假单胞菌从转铁蛋白中铁载体介导的铁获取。
DOI：
10.1128/iai.52.3.885-891.1986
复制
发表时间：
1986
影响因子：
3.1
通讯作者：
Cox,CD
中科院分区：
文献类型：
--
作者：
Sriyosachati,S;Cox,CD
铜绿假单胞菌与[55Fe]转铁蛋白跨过透析膜，引起铁从转铁蛋白侧移动到膜的细菌侧或透析液侧。尽管细菌能够从转铁蛋白中获取铁用于生长，但铜绿假单胞菌的铁载体未能将与转铁蛋白结合的铁转化为可透析的低分子量螯合物。细菌产生的关键因子是葡萄糖基本培养基产生的酸，而单独添加铁载体时不存在。当在 pH 值介于 5.0 和 6.0 之间的透析测定中使用时，铁载体从转铁蛋白中调动大量铁，该值是在测定中细菌孵育过程中常见的值。当单独测试铁载体时，在 pH 值 5.0 和 6.0 下，pyoverdin 在动员铁穿过透析膜方面比 pyochelin 更有效，但在 pH 7.4 下两者都没有明显的活性。从伴清蛋白动员的铁量与从转铁蛋白动员的铁量相当，但在三个pH值下乳铁蛋白的释放量可以忽略不计。当两种铁载体结合时，铁动员水平与单独的脓毒素所证明的水平相同。当去除透析膜并将细菌与铁载体和转铁蛋白混合时，脓毒蛋白在介导铁转运方面再次比脓毒素更活跃。尽管在 pH 7.4 时未检测到绿脓杆菌介导的铁动员，但存在转运。因此，细菌似乎有助于铁载体从转铁蛋白中动员铁。
Pseudomonas aeruginosa placed across a dialysis membrane from [55Fe]transferrin caused the mobilization of the iron from the transferrin side to the bacterial or dialysate side of the membrane. Although the bacteria were capable of obtaining iron from transferrin for growth, the siderophores of P. aeruginosa failed to convert iron bound to transferrin into dialyzable, low-molecular-weight chelates. The crucial factor produced by the bacteria which was not present when the siderophores were added alone was the acid produced from the glucose minimal medium. The siderophores mobilized considerable iron from transferrin when used in the dialysis assay at pH values between 5.0 and 6.0, values which were commonly found during incubation of bacteria in the assays. When the siderophores were tested individually, pyoverdin was more effective than pyochelin in mobilizing iron across dialysis membranes at pH values of 5.0 and 6.0, but neither had appreciable activity at pH 7.4. The amounts of iron mobilized from conalbumin were comparable to the amounts from transferrin, but there was negligible release from lactoferrin at the three pH values. When the two siderophores were combined, the level of iron mobilization was identical to that demonstrated by pyoverdin alone. When the dialysis membrane was removed and the bacteria were mixed with the siderophores and transferrin, pyoverdin was again more active than pyochelin in mediating iron transport. Although no pyochelin-mediated iron mobilization could be detected at pH 7.4, there was transport. Therefore, the bacteria appeared to be aiding the siderophores in iron mobilization from transferrin.