National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
米国
引用
ジャーナル: Sci Adv / 年: 2020 タイトル: Pathogenic siderophore ABC importer YbtPQ adopts a surprising fold of exporter. 著者: Zhiming Wang / Wenxin Hu / Hongjin Zheng / 要旨: To fight for essential metal ions, human pathogens secrete virulence-associated siderophores and retake the metal-chelated siderophores through a subfamily of adenosine triphosphate (ATP)-binding ...To fight for essential metal ions, human pathogens secrete virulence-associated siderophores and retake the metal-chelated siderophores through a subfamily of adenosine triphosphate (ATP)-binding cassette (ABC) importer, whose molecular mechanisms are completely unknown. We have determined multiple structures of the yersiniabactin importer YbtPQ from uropathogenic (UPEC) at inward-open conformation in both and substrate-bound states by cryo-electron microscopy. YbtPQ does not adopt any known fold of ABC importers but surprisingly adopts the fold of type IV ABC exporters. To our knowledge, it is the first time an exporter fold of ABC importer has been reported. We have also observed two unique features in YbtPQ: unwinding of a transmembrane helix in YbtP upon substrate release and tightly associated nucleotide-binding domains without bound nucleotides. Together, our study suggests that siderophore ABC importers have a distinct transport mechanism and should be classified as a separate subfamily of ABC importers.