ジャーナル: EMBO J / 年: 2013 タイトル: Structure of a bacterial type IV secretion core complex at subnanometre resolution. 著者: Angel Rivera-Calzada / Rémi Fronzes / Christos G Savva / Vidya Chandran / Pei W Lian / Toon Laeremans / Els Pardon / Jan Steyaert / Han Remaut / Gabriel Waksman / Elena V Orlova / 要旨: Type IV secretion (T4S) systems are able to transport DNAs and/or proteins through the membranes of bacteria. They form large multiprotein complexes consisting of 12 proteins termed VirB1-11 and ...Type IV secretion (T4S) systems are able to transport DNAs and/or proteins through the membranes of bacteria. They form large multiprotein complexes consisting of 12 proteins termed VirB1-11 and VirD4. VirB7, 9 and 10 assemble into a 1.07 MegaDalton membrane-spanning core complex (CC), around which all other components assemble. This complex is made of two parts, the O-layer inserted in the outer membrane and the I-layer inserted in the inner membrane. While the structure of the O-layer has been solved by X-ray crystallography, there is no detailed structural information on the I-layer. Using high-resolution cryo-electron microscopy and molecular modelling combined with biochemical approaches, we determined the I-layer structure and located its various components in the electron density. Our results provide new structural insights on the CC, from which the essential features of T4S system mechanisms can be derived.
ダウンロード / ファイル: emd_2233.map.gz / 形式: CCP4 / 大きさ: 15.3 MB / タイプ: IMAGE STORED AS FLOATING POINT NUMBER (4 BYTES)
注釈
Subnanometer reconstruction of the pKM101 type IV secretion system core complex digested with elastase
ボクセルのサイズ
X=Y=Z: 2.08 Å
密度
表面レベル
登録者による: 0.23 / ムービー #1: 0.23
最小 - 最大
-3.08228016 - 5.1629281
平均 (標準偏差)
0.01930921 (±0.22263518)
対称性
空間群: 1
詳細
EMDB XML:
マップ形状
Axis order
X
Y
Z
Origin
-79
-80
-80
サイズ
160
160
160
Spacing
160
160
160
セル
A=B=C: 332.8 Å α=β=γ: 90.0 °
CCP4マップ ヘッダ情報:
mode
Image stored as Reals
Å/pix. X/Y/Z
2.08
2.08
2.08
M x/y/z
160
160
160
origin x/y/z
0.000
0.000
0.000
length x/y/z
332.800
332.800
332.800
α/β/γ
90.000
90.000
90.000
start NX/NY/NZ
-36
-30
-80
NX/NY/NZ
73
61
161
MAP C/R/S
1
2
3
start NC/NR/NS
-80
-79
-80
NC/NR/NS
160
160
160
D min/max/mean
-3.082
5.163
0.019
-
添付データ
-
試料の構成要素
-
全体 : traN/traO/traF complex encoded by pKM101 digested with 0.02 mg ml...
全体
名称: traN/traO/traF complex encoded by pKM101 digested with 0.02 mg ml-1 of elastase for 40 min at room temperature
要素
試料: traN/traO/traF complex encoded by pKM101 digested with 0.02 mg ml-1 of elastase for 40 min at room temperature
タンパク質・ペプチド: traF
タンパク質・ペプチド: traO
タンパク質・ペプチド: traN
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超分子 #1000: traN/traO/traF complex encoded by pKM101 digested with 0.02 mg ml...
超分子
名称: traN/traO/traF complex encoded by pKM101 digested with 0.02 mg ml-1 of elastase for 40 min at room temperature タイプ: sample / ID: 1000 / 詳細: monodisperse / 集合状態: 14-mer / Number unique components: 3
空間: REAL / プロトコル: FLEXIBLE FIT / 当てはまり具合の基準: Correlation
得られたモデル
PDB-3zbi: Fitting result in the O-layer of the subnanometer structure of the bacterial pKM101 type IV secretion system core complex digested with elastase
PDB-3zbj: Fitting results in the I-layer of the subnanometer structure of the bacterial pKM101 type IV secretion system core complex digested with elastase