Raw, consensus refinement of Msmeg Mce1 transporter (Map0e)
マップデータ
Raw map used as template to generate composite Map0. Map was generated by aligning consensus set of particles that were retracted with a larger boxsize (640 px). Mask was used to exclude LucB.
試料
複合体: Mce1 lipid transporter composed of Mce1 MCE proteins (Mce1ABCDEF) and an ABC transporter (YrbE1A-B, 2 copies of MceG)
タンパク質・ペプチド: Virulence factor Mce family protein Mce1A
タンパク質・ペプチド: Virulence factor Mce family protein Mce1B
タンパク質・ペプチド: Virulence factor Mce family protein Mce1C
タンパク質・ペプチド: Virulence factor Mce family protein Mce1D
タンパク質・ペプチド: Virulence factor Mce family protein Mce1E
タンパク質・ペプチド: Virulence factor Mce family protein Mce1F
タンパク質・ペプチド: ATP-binding protein MceG
タンパク質・ペプチド: ATP-binding protein MceG
タンパク質・ペプチド: ABC transporter permease protein YrbE1A
タンパク質・ペプチド: ABC transporter permease protein YrbE1B
キーワード
Membrane protein complex / ABC transporter / Virulence factor / Lipid transport / MEMBRANE PROTEIN
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
PEW-00033055
米国
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
U24GM129547
米国
引用
ジャーナル: Nature / 年: 2023 タイトル: Structure of an endogenous mycobacterial MCE lipid transporter. 著者: James Chen / Alice Fruhauf / Catherine Fan / Jackeline Ponce / Beatrix Ueberheide / Gira Bhabha / Damian C Ekiert / 要旨: To replicate inside macrophages and cause tuberculosis, Mycobacterium tuberculosis must scavenge a variety of nutrients from the host. The mammalian cell entry (MCE) proteins are important virulence ...To replicate inside macrophages and cause tuberculosis, Mycobacterium tuberculosis must scavenge a variety of nutrients from the host. The mammalian cell entry (MCE) proteins are important virulence factors in M. tuberculosis, where they are encoded by large gene clusters and have been implicated in the transport of fatty acids and cholesterol across the impermeable mycobacterial cell envelope. Very little is known about how cargos are transported across this barrier, and it remains unclear how the approximately ten proteins encoded by a mycobacterial mce gene cluster assemble to transport cargo across the cell envelope. Here we report the cryo-electron microscopy (cryo-EM) structure of the endogenous Mce1 lipid-import machine of Mycobacterium smegmatis-a non-pathogenic relative of M. tuberculosis. The structure reveals how the proteins of the Mce1 system assemble to form an elongated ABC transporter complex that is long enough to span the cell envelope. The Mce1 complex is dominated by a curved, needle-like domain that appears to be unrelated to previously described protein structures, and creates a protected hydrophobic pathway for lipid transport across the periplasm. Our structural data revealed the presence of a subunit of the Mce1 complex, which we identified using a combination of cryo-EM and AlphaFold2, and name LucB. Our data lead to a structural model for Mce1-mediated lipid import across the mycobacterial cell envelope.
ダウンロード / ファイル: emd_29232.map.gz / 形式: CCP4 / 大きさ: 1000 MB / タイプ: IMAGE STORED AS FLOATING POINT NUMBER (4 BYTES)
注釈
Raw map used as template to generate composite Map0. Map was generated by aligning consensus set of particles that were retracted with a larger boxsize (640 px). Mask was used to exclude LucB.
ボクセルのサイズ
X=Y=Z: 0.8255 Å
密度
表面レベル
登録者による: 0.15
最小 - 最大
-0.7296897 - 1.2698982
平均 (標準偏差)
0.000005381307 (±0.018287499)
対称性
空間群: 1
詳細
EMDB XML:
マップ形状
Axis order
X
Y
Z
Origin
0
0
0
サイズ
640
640
640
Spacing
640
640
640
セル
A=B=C: 528.32 Å α=β=γ: 90.0 °
-
添付データ
-
ハーフマップ: Half map A for raw map used as template to generate composite map.
名称: Mce1 lipid transporter composed of Mce1 MCE proteins (Mce1ABCDEF) and an ABC transporter (YrbE1A-B, 2 copies of MceG) タイプ: complex / ID: 1 / 親要素: 0 / 含まれる分子: all 詳細: Complex was isolated directly from Mycobacterium smegmatis by pulling down MceG-GFP using GFP-affinity purification and size exclusion chromatography.
由来(天然)
生物種: Mycolicibacterium smegmatis MC2 155 (バクテリア)
+
分子 #1: Virulence factor Mce family protein Mce1A
分子
名称: Virulence factor Mce family protein Mce1A / タイプ: protein_or_peptide / ID: 1 / 光学異性体: LEVO
タイプ: MAXIMUM LIKELIHOOD / ソフトウェア - 名称: cryoSPARC (ver. 3.3.1)
最終 角度割当
タイプ: MAXIMUM LIKELIHOOD / ソフトウェア - 名称: cryoSPARC (ver. 3.3.1)
FSC曲線 (解像度の算出)
-
原子モデル構築 1
詳細
Model was initial fitted into the map using Chimera follow-by rigid body refinement in PHENIX. Models were further refined using PHENIX real-space refinement and then manually inspected in Coot.
精密化
空間: REAL / プロトコル: FLEXIBLE FIT 当てはまり具合の基準: Cross-correlation coefficient