5Y8A

Periplasmic heme-binding protein BhuT in complex with two hemes (holo-2 form)

「5GJ1」から置き換えられました

5Y8A の概要

• エントリーDOI: 10.2210/pdb5y8a/pdb
• 関連するPDBエントリー: 5GIZ 5GJ3
• 分子名称: Putative hemin transport system, substrate-binding protein, PROTOPORPHYRIN IX CONTAINING FE, CALCIUM ION, ... (4 entities in total)
• 機能のキーワード: metal transport, transport protein
• 由来する生物種: Burkholderia cenocepacia (strain ATCC BAA-245 / DSM 16553 / LMG 16656 / NCTC 13227 / J2315 / CF5610)
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 58538.08

構造登録者

Nakamura, N.,Naoe, Y.,Rahman, M.M.,Shiro, Y.,Sugimoto, H. (登録日: 2017-08-20, 公開日: 2017-10-11, 最終更新日: 2023-11-22)

主引用文献

Naoe, Y.,Nakamura, N.,Rahman, M.M.,Tosha, T.,Nagatoishi, S.,Tsumoto, K.,Shiro, Y.,Sugimoto, H.
Structural basis for binding and transfer of heme in bacterial heme-acquisition systems
Proteins, 85:2217-2230, 2017

PubMed Abstract: Periplasmic heme-binding proteins (PBPs) in Gram-negative bacteria are components of the heme acquisition system. These proteins shuttle heme across the periplasmic space from outer membrane receptors to ATP-binding cassette (ABC) heme importers located in the inner-membrane. In the present study, we characterized the structures of PBPs found in the pathogen Burkholderia cenocepacia (BhuT) and in the thermophile Roseiflexus sp. RS-1 (RhuT) in the heme-free and heme-bound forms. The conserved motif, in which a well-conserved Tyr interacts with the nearby Arg coordinates on heme iron, was observed in both PBPs. The heme was recognized by its surroundings in a variety of manners including hydrophobic interactions and hydrogen bonds, which was confirmed by isothermal titration calorimetry. Furthermore, this study of 3 forms of BhuT allowed the first structural comparison and showed that the heme-binding cleft of BhuT adopts an "open" state in the heme-free and 2-heme-bound forms, and a "closed" state in the one-heme-bound form with unique conformational changes. Such a conformational change might adjust the interaction of the heme(s) with the residues in PBP and facilitate the transfer of the heme into the translocation channel of the importer.

PubMed: 28913898
DOI: 10.1002/prot.25386

実験手法

X-RAY DIFFRACTION (2.001 Å)