细菌内依赖TonB的外膜铁转运体的研究进展

铁是细菌所必需的微量营养元素,但由于易被氧化溶解性低,生物体的利用率大大降低。细菌在进化过程中形成多种策略来吸收环境中低浓度的铁,不同类型铁的吸收通过外膜上依赖TonB的转运体(TonB-dependent transporters,TBDTs)完成,TBDTs结合不同形式的铁复合物,通过内膜上的TonB-ExbB-ExbD复合物提供能量完成转运,对其机制的研究一直是微生物基础生命活动研究中的热点问题。近年来新鉴定了一些TBDTs的结构,并对其功能和转运机制有了更深入的研究,对此进行了综述,不仅有助于进一步揭示细菌的铁转运机制,而且有助于寻找新的靶位点以开发新的治疗药物。

Progress of TonB-Dependent Transporters for Iron on Outer Membrane in Bacteria

Although iron is the necessary nutrient element for bacteria,its availability is greatly reduced by its low solubility.To acquire iron,bacteria have evolved a range of strategies mechanism.Iron absorbing is performed through the TonB-dependent transporters(TBDTs) on outer membrane of bacteria.TBDTs bind and transport ferric chelates coupled with energy providing by a complex of three inner membrane proteins,TonB-ExbB-ExbD.The mechanism has been the hot spot study on based life activities of microorganism.In recent years,structures of some new TBDTs have been identified,and researches has been done on these TBDTs’ function and transport mechanism.