ジャーナル: Nat Plants / 年: 2019 タイトル: Biogenic regions of cyanobacterial thylakoids form contact sites with the plasma membrane. 著者: Anna Rast / Miroslava Schaffer / Sahradha Albert / William Wan / Stefan Pfeffer / Florian Beck / Jürgen M Plitzko / Jörg Nickelsen / Benjamin D Engel / 要旨: Little is known about how the photosynthetic machinery is arranged in time and space during the biogenesis of thylakoid membranes. Using in situ cryo-electron tomography to image the three- ...Little is known about how the photosynthetic machinery is arranged in time and space during the biogenesis of thylakoid membranes. Using in situ cryo-electron tomography to image the three-dimensional architecture of the cyanobacterium Synechocystis, we observed that the tips of multiple thylakoids merge to form a substructure called the 'convergence membrane'. This high-curvature membrane comes into close contact with the plasma membrane at discrete sites. We generated subtomogram averages of 70S ribosomes and array-forming phycobilisomes, then mapped these structures onto the native membrane architecture as markers for protein synthesis and photosynthesis, respectively. This molecular localization identified two distinct biogenic regions in the thylakoid network: thylakoids facing the cytosolic interior of the cell that were associated with both marker complexes, and convergence membranes that were decorated by ribosomes but not phycobilisomes. We propose that the convergence membranes perform a specialized biogenic function, coupling the synthesis of thylakoid proteins with the integration of cofactors from the plasma membrane and the periplasmic space.
ダウンロード / ファイル: emd_4603.map.gz / 形式: CCP4 / 大きさ: 762.2 MB / タイプ: IMAGE STORED AS SIGNED INTEGER (2 BYTES)
注釈
Volta phase plate in situ tomogram of a Synechocystis cell
ボクセルのサイズ
X=Y=Z: 13.68 Å
密度
最小 - 最大
-258 - 116
平均 (標準偏差)
2.1207142 (±10.92974)
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
928
928
464
Spacing
928
928
464
セル
A: 12695.04 Å / B: 12695.04 Å / C: 6347.52 Å α=β=γ: 90.0 °
CCP4マップ ヘッダ情報:
mode
Image stored as Integer*27
Å/pix. X/Y/Z
13.68
13.68
13.68
M x/y/z
928
928
464
origin x/y/z
0.000
0.000
0.000
length x/y/z
12695.040
12695.040
6347.520
α/β/γ
90.000
90.000
90.000
start NX/NY/NZ
212
211
153
NX/NY/NZ
80
102
186
MAP C/R/S
1
2
3
start NC/NR/NS
0
0
0
NC/NR/NS
928
928
464
D min/max/mean
-258.000
116.000
2.121
-
添付データ
-
試料の構成要素
-
全体 : Volta phase plate in situ tomogram of a Synechocystis cell
全体
名称: Volta phase plate in situ tomogram of a Synechocystis cell
要素
細胞: Volta phase plate in situ tomogram of a Synechocystis cell
-
超分子 #1: Volta phase plate in situ tomogram of a Synechocystis cell
超分子
名称: Volta phase plate in situ tomogram of a Synechocystis cell タイプ: cell / ID: 1 / 親要素: 0
由来(天然)
生物種: Synechocystis sp. PCC 6803 (バクテリア)
-
実験情報
-
構造解析
手法
クライオ電子顕微鏡法
解析
電子線トモグラフィー法
試料の集合状態
cell
-
試料調製
緩衝液
pH: 7
グリッド
モデル: Quantifoil R1.2/1.3 / 材質: COPPER / メッシュ: 200
凍結
凍結剤: ETHANE-PROPANE / チャンバー内湿度: 90 % / チャンバー内温度: 297 K / 装置: FEI VITROBOT MARK IV / 詳細: Blotting time: 10 sec Blot force: 10.
詳細
Vitrious Synechocystis cell milled with a Ga2+ focused ion beam.
切片作成
集束イオンビーム - 装置: OTHER / 集束イオンビーム - イオン: OTHER / 集束イオンビーム - 電圧: 30 kV / 集束イオンビーム - 電流: 0.03 nA / 集束イオンビーム - 時間: 3600 sec. / 集束イオンビーム - 温度: 93 K / 集束イオンビーム - Initial thickness: 2000 nm / 集束イオンビーム - 最終 厚さ: 150 nm 集束イオンビーム - 詳細: The value given for _emd_sectioning_focused_ion_beam.instrument is FEI Quanta FIB. This is not in a list of allowed values set(['DB235', 'OTHER']) so OTHER is written into the XML file.