我们感谢威廉·马戈林医生征求意见。我们感谢来自博士的SerialEM的支持。大卫Mastronarde和陈旭。 DM，BH和JL被授予R01AI087946从国家过敏和传染病研究所，资助R01GM110243和R01GM107629从普通医学科学研究所（NIGMS）和格兰特AU-1714从韦尔奇基金会的支持。直接电子探测器是由美国卫生奖S10OD016279国家机构。

1.小细准备<ol><li>为了使S.菌微细胞，变换1微升质粒pBS58，其组成型表达的大肠杆菌细胞分裂的基因ftsQ，ftsA，和ftsZ超从低拷贝壮观霉素抗性质粒入5微升电感受链霉素抗性5a血清型（M90T钐）细胞通过电穿孔的在2.5千伏为5毫秒，以1毫米试管。 </li><li>商店微细胞的样品在-80℃下在15％甘油在1.5ml微管中的低温。当准备使用时，刮大约5微升用枪头从unthawed微管细胞和悬浮细胞在4毫升的胰蛋白酶大豆肉汤与壮观霉素加入到100微克/毫升的浓度。成长O / N在37℃。 </li><li>吸管2毫升培养从1.2入200ml胰蛋白酶大豆肉汤与壮观霉素再次加入到100微克/毫升的浓度。在37℃下生长至晚对数期。 </li><li>为了丰富小细胞，离心200毫升从1.3的培养物在1000×g离心5分钟。小心倾上清液部分到一个新的离心管中并离心以20,000×g离心10分钟。仔细倒出并丢弃上清液部分，并轻轻混合颗粒使用一个枪头剩余的液体和到1.5ml微量离心管中传输大约100微升沉淀混合物。 </li></ol> 2. EM网格准备<ol><li>放置一个R 2/2多孔碳膜200目铜网上碳朝上载玻片上。 注:R 2/2 200目网格被选择以最大化的倾斜系列可被设置以获得在一个单一的网格，同时仍然支持试样和放置碳膜的边缘，在摄像机的视场的数目在所需的倍率。精细的网格的网格和更小的多孔碳薄膜如R1.2 / 1.3 400目，可用于成像在更高的放大倍率样本;较大的多孔碳薄膜，如R3.5 / 1 200目可使用d表示样品成像在较低的放大率，或如果显微照片不应该包含具有较大的间距，例如R 1的碳边缘和多孔碳薄膜/ 4 200目可以用来帮助进行对准阶段到感兴趣的区域和保护区域从过度曝光在聚焦和跟踪​​例程。 </li><li>放置在辉光放电装置在平台上的幻灯片。 注意:我们使用一个内部装置，其中在阳极和平台已加工到真空干燥器中，由一个高频发生器供电。形成真空后，附加高频发生器探针探针上的阳极和电源1分钟到辉光放电的网格。必要的时间，以辉光放电网格的范围可以从几秒钟到一分钟。改变辉光放电时间可用于诊断问题随试样浓度和出现干燥无玻璃体冰网格。 </li><li>与一组镊子除去网格，并锁定镊子关闭用弹性b和。 </li><li>加入100微升10纳米的胶体金溶液的微量离心管中，在1.4中制备的微细胞，并通过轻弹管用手指混合。随着新的吸管发生4微升在2.2编写电网的混合物。 注:胶体金是有各种尺寸和护理提供应采取的金的尺寸大于5个像素定在所获取的放大要处理的显微照片的像素大小，而不是过大，晦涩特征出于兴趣。 </li><li>准备切入冻结装置;充满液氮的外冷冻容器，然后装满液体乙烷内腔。附加镊子与电网向柱塞杆和柱塞杆锁定到升高位置。 注:用于描述使用商业暴跌冻结设备的协议，见扬库等 [20]。 </li><li>通过仔细触摸一片滤纸到t吸干电网他滴样品直到网格和滤纸分离并在滤纸上的芯吸停止之间的弯液面，然后立即释放柱塞杆，冻结的网格。小心地从柱塞杆除去钳子，并放置在网格到网格支架。 </li><li>用液态氮填充装载区和吸收泵容器准备冷冻电镜中转站。一旦装载区域是在液氮温度下发生的网格支架，并在装载区在显微镜标本盒。 </li><li>小心地取出锁环，这是早期的波拉显微镜或以后的型号C风格的夹环或者是小螺纹锁环;使用镊子将EM电网进入墨盒，然后轻轻地重新安装锁环放回盒固定网格。 </li><li>从显微镜中取出多个样品支架，并将其安装到中转站。将试样墨盒插入墨盒使用的镊子持有人Ð缩回从装载区域中的保持器和多个试样保持器传回的显微镜。 注:参见陈等人 21为可视的协议细节2.1-2.9。 </li></ol> 3.高通量自动化倾斜系列集合<ol><li>集低倍率地图的<ol><li>通过点击"打开"的SerialEM 10的"导航"菜单中打开一个新的浏览器窗口（http://bio3d.colorado.edu/SerialEM） </li><li>查找包含可接受的成像条件方格（ 即薄冰，没有污染，感兴趣的主题）使用荧光屏幕在低倍率（〜2,300X为小细胞标本）。 注:[可选:该步骤可以与SerialEM通过剪接整个电网自动化，但它能够更快简单地手动选择少数地区] </li><li>调整阶段eucentric高度倾斜样品架至50°再调整的z高度，直到该级的XY平移是最小的倾斜和非倾斜视图之间。 </li><li>移动到方格的中心，点击Navigator窗口中的"添加阶段名次"按钮来保存当前舞台上的地位。 </li><li>继续步骤3.1.1-4以上，直到所有接受方格级职位已被保存。 </li><li>通过单击"文件"菜单中的"新建蒙太奇"打开一个新的蒙太奇MRC文件。在蒙太奇设置对话框打开后，选择一个数字X和Y枚将收购整个方格（ 例如，10×10的标准的200网格）的。使用高分级，如8，选择"移动相反的图像转移阶段"和"跳过用于对齐件相关"单选按钮。 </li><li>在浏览器窗口中单击第一个舞台上的地位，并把它设置为通过检查"采集"复选框被收购。在浏览器窗口中的每个阶段的位置重复此。 </li><li>打开浏览器获取对话框通过在"导航"菜单中单击"获取的积分"。选中"采集地图图像"和"粗eucentricity"复选框，并确保所有其他复选框都未选中。点击"继续"，收集了蒙太奇在每个阶段的位置。 </li></ol></li><li>倾斜系列采集<ol><li>在浏览器窗口中选择被收购的地图之一，并点击"载入地图"按钮。 </li><li>在浏览器窗口中，单击"添加点"按钮，然后选择点在其中获得倾斜系列地图。然后点击"停止添加点"按钮。重复每个收集的地图。 </li><li>在相机菜单中选择"参数"，并为重点，审判和记录模式定义的参数。 [可选:剂量分级的数据可以为拍摄模式下的参数指定] </li><li>选择Navigator窗口中的一个点，并检查"倾斜系列9;复选框。在打开选择参数倾翻式系列设置对话窗口所需的倾斜系列采集。重复在导航窗口中选定点的休息，但不要选择地图。 </li><li>在导航菜单中再次选择"获取的积分"。在导航器获取对话框中选择"重新调整项"，自动对焦"和"粗eucentricity"的初步任务，并选择"获取倾斜系列"作为首要任务，并选择"关闭柱阀，在结束"当所有关闭列点的已收集。一旦继续倾斜系列将在每个地图每个点采集。 </li></ol></li></ol> 4.高通量自动化倾斜系列加工和重建使用Tomoauto <ol><li>梁诱发运动的剂量分次数据修正[可选] 注:Tomoauto使用MOTIONCORR 22（http://cryoem.ucsf.edu/software/driftcorr.ht毫升），从剂量分次取出显微光束引起的运动。 NOTIONCORR 16必须安装在系统上。 <ol><li>与原来的倾斜系列，从SerialEM 10在当前工作目录输出日志和个人剂量分级的所有图像，在终端执行以下命令: dose_fractioned_to_stack &lt;filename.st&gt; &lt;filename.st&gt;是倾斜系列以处理的名称。 </li></ol></li><li>对齐的倾斜系列和重建 注:Tomoauto默认使用IMOD 13（http://bio3d.colorado.edu/imod/）来处理倾斜系列自动基准模型生成，比对，确定对比度传递函数（CTF），CTF校正23，和重建。另外用户在tomoauto选择使用RAPTOR 24（包含在IMOD）的自动化基准模型生成，周大福FIND4 25（http://grigoriefflab.janelia.org/ctf）来确定CTF，和tomo3d 26（https://sites.google.com/site/3demimageprocessing/tomo3d），用于重建或以软件产品的任何组合组态。此每个包中可用的配置以及参数是由可以被编辑以适合在实验室中最常用的值，同时本地配置文件还可以创建用于特定样本细节的参数，收集一个全局配置文件处理设置或个人倾斜系列。那些希望使用所有包装必须安装在系统上。 <ol><li>随着倾斜系列在当前的工作目录，在终端执行命令 tomoauto --CTF --mode =对齐&lt;filename.st&gt; &lt;fid_diam&gt; &lt;filename.st&gt;是倾斜系列进行处理并&lt;fid_diam&gt;是diame之三的以纳米为单位的基准标记。此命令将调整和自动估计倾斜系列的CTF。有可能跳过CTF处理通过从命令中--CTF选项。 </li><li>检查对准倾斜一系列可视在对准处理任何明显的误差和通过执行的命令检查所估计的CTF: 3dmod &lt;文件名​​&gt; .ali submfg &lt;文件名​​&gt; _ctfplotter.com 分别为， 其中 &lt;文件名​​&gt;是倾斜系列无后缀的名称。同时检查tomoauto命令的输出看到的一致性，这是调整的质量进行定量统计生成的平均剩余误差。 </li><li>给定一个可接受的定位通过执行命令进行处理: tomoau以--CTF --mode =重构&lt;filename.st&gt; &lt;fid_diam&gt; 使用相同的用户替换为4.2.1。此命令将纠正周大福，从倾斜系列擦除基准标记和计算的重建。再次CTF处理可以跳过在4.2.1。 </li><li> [可选]要跳过目视检查步骤，并全面实现自动化处理与重建执行命令 tomoauto --CTF &lt;filename.st&gt; &lt;fid_diam&gt; </li><li> [可选]要使用特定的本地配置，请参阅如何生成一个本地配置文件tomoauto文件，然后执行命令 tomoauto [选项] -L &lt;local_config&gt; &lt;filename.st&gt; &lt;fid_diam&gt; 其中&lt;local_config&gt;是本地的conf名iguration文件。 </li></ol></li></ol> 5.子断层扫描平均注:我们使用的i3包15（http://www.electrontomography.org/）来处理子断层扫描平均的实验，但协议中所述，一般适用于大多数可用的子断层扫描平均软件packages16to处理子断层扫描平均的实验，但协议中所述，一般适用于大多数可用的子断层扫描平均软件包16-18。 <ol><li>随着当前工作目录重建的断层图像开拓断层扫描粒子采摘通过执行以下命令: tomopick &lt;文件名&gt; .REC 其中&lt;文件名&gt;是在4.2.2。在打开使用鼠标左键点击第一个基础体温，然后针尖选择一个injectisome并使用向上和向下箭头键来即兴通过tomogra的切片窗口米选择这种方式的所有可见injectisomes。这存储在文本文件中定义的结构的长轴以及推定的两个3欧拉角描述结构的取向的坐标。 </li><li>计算提取从通过执行命令集中在定义的长轴的中点的断层图像400 3体素立方体: 夹大小调整-cx &lt;X&gt; -cy &lt;Y&gt; -cz &lt;Z&gt; -ix 400 -Iy 400 -Iz 400 &lt;文件名&gt; .REC &lt;文件名&gt; _001.mrc 其中&lt;x&gt;，&lt;y&gt;和&lt;Z&gt;是结构的中点坐标和&lt;文件名&gt;是在4.2.2。所提取的立方体的尺寸应该由结构和所用的放大倍数而变化，并且应该足够大，以适当地包围感兴趣的结构，这对于该样品是400 3体素。 </li><li>下采样（斌）子断层扫描由四个因素通过执行以下命令，以减少计算时间初始校准: binvol -b 4 &lt;文件名&gt; _001.mrc &lt;文件​​名&gt; _001.bin4.mrc 其中&lt;文件名&gt;是在5.2。 </li><li>应用决定欧拉角子断层和计算的全球平均通过执行以下命令来产生初始模板。 I3totsum.sh </li><li>对准并使用胞质区域的二元分类掩模分类向下抽样子断层图像。在傅立叶空间中进行的子断层图像平均化，以尽量减少缺失槽楔工件断层扫描的特性。对于分档4的数据，请使用SAMPFACT ="4 4 4"。 i3mramsacls.sh </li><li>重复步骤5.5采用子断层图像下采样由两个（SAMPFACT =＆一个因子＃34; 2 2 2"），并再次与原始数据（SAMPFACT ="1 1 1"）。 i3mramsacls.sh </li></ol>

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作者宣称，他们有没有竞争的财务权益。

此处所描述的高通量方法，使我们能够处理1917低温倾斜系列和产生超过4500分断层图像的完好S的菌 injectisome 19。所收集的数据导致原位 injectisome的详细的表征，包括胞质排序复杂。该方法也被用来可视化几个突变的细胞与特异性缺失推定的蛋白质组分，这有助于阐明injectisome的排序平台的组成。我们的方法提供了新的途径，调查injectisome的结构与功能的关系。其结果是?...

III型分泌系统（T3SS）是必不可少的毒力决定于许多革兰氏阴性病原体。的injectisome，也被称为针复杂，是所需的效应蛋白直接易位从细菌到真核宿主细胞1,2中央T3SS机。所述injectisome包括细胞外针，一个基体，和胞质复杂也是已知作为拣杂3。先前的研究已阐明了从沙门氏菌和 志贺氏菌纯化的injectisomes的3-D结构，随着主要基体蛋白4,5的原子结构。最近在从沙门氏菌， 志贺氏菌和耶尔森氏菌 injectisomes 原位结构进行了揭示的低温的ET 6 7，然而，胞质复杂，效应子选择和针组件必需的，还没有被可视化这些结构。 低温-ET是MOSŤ合适技术其天然细胞环境（原位）内成像分子机器在纳米级分辨率。尽管如此，通过Cryo-ET可达到的分辨率由样品厚度的限制。为了克服缺点，我们在毒痢疾杆菌菌株进行基因改造，以产生小细胞的冷冻ET足够薄成像完好injectisomes。冷冻的ET的另一个限制是样品诱导的电子束，它非常快速地破坏在样品中的高分辨率信息的辐射的敏感性。其结果是，非常低剂量用于个体倾斜图像，使合适的剂量可以分布在全倾斜系列。这大大降低了在最终的重建的信噪比（SNR），这使得难以区分的大量的断层图像噪声的被检体的结构特征和限制了可以由永冻达到的分辨率ET。 Conventi可用于Onal地区的图像处理，如傅立叶和现实空间滤波器以及向下采样，以增加对比度，但在过滤掉大部分的高分辨率信息的费用。近来，子断层图像平均化使得有可能大大提高了信噪比并随后在某些情况下，以亚纳米水平8,9的尾声。配合物的更详细的分析成为可能通过计算提取数千含子断层图像从原来的断层图像，然后对准并平均所述子断层图像感兴趣的区域，以确定在具有较高SNR和更高分辨率的原位复杂的结构。这些方法可以用遗传学方法，以提供更大的见解大分子组装，并在天然细胞环境的动态构象进行集成。 在一般情况下，几十甚至几十万子断层需要，以确定高被平均-分辨率结构原位 。采集的倾斜系列足够数量需要产生这种大数目的子断层图像很快成为一个瓶颈。所得倾斜系列往往受光束诱发移位，阶段齿隙，以及倍率，旋转和歪斜缺陷，这必须得到解决，以使倾斜系列对准前重建。倾斜系列典型地通过跟踪金基准标记，这是传统选过倾斜系列的检查手动，引起另一个瓶颈对齐。许多软件包已通过计算机控制的电子显微镜10，11，12，倾斜系列对准和重建13，14和子断层图像平均15-18开发用于自动倾斜系列采集。由于这些产品的处理在低温的ET的工作流分立操作，就变成希望建立一个更高的抽象水平进入过程的Systema角度讲简化整个计划到一个单一的管道。因此，我们开发了软件包装库"tomoauto"旨在组织一些这些包成一个单一的半自动化单元，允许简单的用户操作，同时保持以集中的方式各成分的完整配置。该库是开源的，有据可查的，不断发展和可以自由使用，定制开发或进一步集成通过网上远程源代码库（http://github.com/DustinMorado/tomoauto）的手段。 这种高通量冷冻ET管道已被用来可视化完好injectisomes S中菌的微细胞。使用该方法生成总共1917断层图像，揭示一个高分辨率在完整的机器的原位结构，包括由子断层图像均 19确定的细胞质分拣平台。连同野生型和米的分子模拟utant机，我们的高通量管道提供了一种新的途径，以了解在天然细胞环境的完整injectisome的结构和功能。

<table border="0" cellpadding="0" cellspacing="0" width="651">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:160px;">Glycerol</td>
			<td style="width:211px;">Sigma-Aldrich</td>
			<td style="width:116px;">G9012</td>
			<td style="width:164px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:160px;">Tyrptic Soy Broth</td>
			<td style="width:211px;">Sigma-Aldrich</td>
			<td style="width:116px;">22092</td>
			<td style="width:164px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:160px;">Spectinomycin</td>
			<td style="width:211px;">Sigma-Aldrich</td>
			<td style="width:116px;">S0692</td>
			<td style="width:164px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:160px;">Electroporation Apparatus</td>
			<td style="width:211px;">Bio-rad</td>
			<td>165-2100</td>
			<td style="width:164px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:160px;">1 mm Cuvette</td>
			<td style="width:211px;">BTX</td>
			<td>45-0124</td>
			<td style="width:164px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:160px;">1.5 mL Cryogenic Tube</td>
			<td style="width:211px;">Thermoscientific</td>
			<td>5000-1020</td>
			<td style="width:164px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:160px;">1.5 mL Microcentrifuge Tube</td>
			<td style="width:211px;">Sigma-Aldrich</td>
			<td>Z336769</td>
			<td style="width:164px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:160px;">Holey Carbon Grids</td>
			<td style="width:211px;">Quantifoil 
			(Electron Microscopy Sciences)</td>
			<td style="width:116px;">Q2100CR2</td>
			<td style="width:164px;">R2/2 200 Cu</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:160px;">Glow Discharge Device</td>
			<td style="width:211px;">In-House</td>
			<td style="width:116px;"></td>
			<td style="width:164px;">Commercial Alternative Available</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:160px;">Vacuum Desiccator</td>
			<td style="width:211px;">Sigma-Aldrich</td>
			<td style="width:116px;">Z119016&#160;</td>
			<td style="width:164px;">Used in In-House Glow Discharge Device</td>
		</tr>
		<tr height="105">
			<td height="105" style="height:105px;width:160px;">High-Frequency Generator</td>
			<td style="width:211px;">Electro-Technic Products</td>
			<td style="width:116px;">BD-10A</td>
			<td style="width:164px;">Used in In-House Glow Discharge Device.&#160; CAUTION: This device generates high voltages.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:160px;">Centrifuge</td>
			<td style="width:211px;"></td>
			<td style="width:116px;"></td>
			<td style="width:164px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:160px;">Forceps</td>
			<td style="width:211px;">Dumont 
			(Electron Microscopy Sciences)</td>
			<td style="width:116px;">72705-D</td>
			<td style="width:164px;">Style 5 Anti-magnetic</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:160px;">Colliodal Gold</td>
			<td style="width:211px;">Aurion</td>
			<td style="width:116px;"></td>
			<td style="width:164px;">BSA 10nm</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:160px;">Filter Paper</td>
			<td style="width:211px;">Whatman</td>
			<td style="width:116px;"></td>
			<td style="width:164px;">#2</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:160px;">Ethane&#160;</td>
			<td style="width:211px;">Matheson Tri-Gas</td>
			<td style="width:116px;">UN1035</td>
			<td style="width:164px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:160px;">Nitrogen</td>
			<td style="width:211px;">Matheson Tri-Gas</td>
			<td style="width:116px;">UN1977</td>
			<td style="width:164px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:160px;">Plunger Device</td>
			<td style="width:211px;">In-House</td>
			<td style="width:116px;"></td>
			<td style="width:164px;">Commercial Alternative Available</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:160px;">Cryogenic Grid Storage Box</td>
			<td style="width:211px;">Electron Microscopy Sciences</td>
			<td style="width:116px;">71166-30</td>
			<td style="width:164px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:160px;">Transmission Electron Microscope</td>
			<td style="width:211px;">FEI</td>
			<td style="width:116px;"></td>
			<td style="width:164px;">Tecnai Polara F30 
			(300 KeV)</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:160px;">Direct Detection Device Camera</td>
			<td style="width:211px;">Gatan</td>
			<td style="width:116px;"></td>
			<td style="width:164px;">K2 Summit</td>
		</tr>
		<tr height="105">
			<td height="105" style="height:105px;width:160px;">Tomogram Acquisiton Software</td>
			<td style="width:211px;">SerialEM</td>
			<td style="width:116px;"></td>
			<td style="width:164px;">http://bio3d.colorado.eud/SerialEM Alternatives: UCSF Tomography, Leginon, FEI Batch Tomography</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:160px;">Beam-induced Motion Correction Software</td>
			<td style="width:211px;">MOTIONCORR</td>
			<td style="width:116px;"></td>
			<td style="width:164px;">http://cryoem.ucsf.edu/software/driftcorr.html Requires &#62;2GB Nvidia GPU</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:160px;">Tilt-Series Alignment Software</td>
			<td style="width:211px;">IMOD</td>
			<td style="width:116px;"></td>
			<td style="width:164px;">http://bio3d.colorado.edu/IMOD Alternatives: XMIPP, Protomo</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:160px;">Automatic Fiducial Marker Modelling Software</td>
			<td style="width:211px;">IMOD</td>
			<td style="width:116px;"></td>
			<td style="width:164px;">Alternatives: RAPTOR (Included in IMOD0 
			(Usable in tomoauto)</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:160px;">CTF Determination Software</td>
			<td style="width:211px;">IMOD</td>
			<td style="width:116px;"></td>
			<td style="width:164px;">Alternatives: CTFFIND http://grigoriefflab.janelia.org/ctf 
			(Usable in tomoauto)</td>
		</tr>
		<tr height="147">
			<td height="147" style="height:147px;width:160px;">Tilt-Series Reconstruction Software</td>
			<td style="width:211px;">tomo3d</td>
			<td style="width:116px;"></td>
			<td style="width:164px;">https://sites.google.com/site/3demimageprocessing/tomo3d Alternatives: IMOD, XMIPP http://xmipp.cnb.csic.es , Protomo</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:160px;">Tilt-Series Automated Processing Software</td>
			<td style="width:211px;">tomoauto</td>
			<td style="width:116px;"></td>
			<td style="width:164px;">https://github.com/DustinMorado/tomoauto</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:160px;">Particle Picking Software</td>
			<td style="width:211px;">i3</td>
			<td style="width:116px;"></td>
			<td style="width:164px;">http://www.electrontomography.org Alternatives: IMOD</td>
		</tr>
		<tr height="126">
			<td height="126" style="height:126px;width:160px;">Subvolume Averaging Software</td>
			<td style="width:211px;">i3</td>
			<td style="width:116px;"></td>
			<td style="width:164px;">Alternatives: PEET http://bio3d.colorado.edu/PEET, Dynamo https://dynamo.bioz.unibas.ch , PyTom http://pytom.org</td>
		</tr>
	</tbody>
</table>

using tomoauto: a protocol for high-throughput automated cryo-electron tomography

Cryo-electron tomography (Cryo-ET) is a powerful three-dimensional (3-D) imaging technique for visualizing macromolecular complexes in their native context at a molecular level. The technique involves initially preserving the sample in its native state by rapidly freezing the specimen in vitreous ice, then collecting a series of micrographs from different angles at high magnification, and finally computationally reconstructing a 3-D density map. The frozen-hydrated specimen is extremely sensitive to the electron beam and so micrographs are collected at very low electron doses to limit the radiation damage. As a result, the raw cryo-tomogram has a very low signal to noise ratio characterized by an intrinsically noisy image. To better visualize subjects of interest, conventional imaging analysis and sub-tomogram averaging in which sub-tomograms of the subject are extracted from the initial tomogram and aligned and averaged are utilized to improve both contrast and resolution. Large datasets of tilt-series are essential to understanding and resolving the complexes at different states, conditions, or mutations as well as obtaining a large enough collection of sub-tomograms for averaging and classification. Collecting and processing this data can be a major obstacle preventing further analysis. Here we describe a high-throughput cryo-ET protocol based on a computer-controlled 300kV cryo-electron microscope, a direct detection device (DDD) camera and a highly effective, semi-automated image-processing pipeline software wrapper library tomoauto developed in-house. This protocol has been effectively utilized to visualize the intact type III secretion system (T3SS) in Shigella flexneri minicells. It can be applicable to any project suitable for cryo-ET.

小细胞S.样品菌 ，收集并处理的结果显示在原理图1采用tomoauto在图2中详述的管道下面。 使用SerialEM 10，其允许高通量倾斜系列采集在上低倍率蒙太奇地图由用户指定的点（ 图3）倾斜系列收集。使用剂量分馏模式直接检测器件照相机上，以减少束诱发运动22（图4），收集显微镜?...

Watch this Scientific Journal Video about Using Tomoauto: A Protocol for High-throughput Automated Cryo-electron Tomography at JoVE.com

Using Tomoauto: A Protocol for High-throughput Automated Cryo-electron Tomography

我们提出如何利用高通量低温电子断层扫描，以确定高分辨率的分子机器的结构原位的协议。该协议允许大量数据要处理，避免了常见的瓶颈，并减少停机时间资源，从而允许用户集中在重要的生物的问题。

使用Tomoauto:一个协议，用于高通量自动化低温电子断层扫描

Cryo-electron tomography (Cryo-ET) is a powerful three-dimensional (3-D) imaging technique for visualizing macromolecular complexes in their native ...

using-tomoauto-protocol-for-high-throughput-automated-cryo-electron

Research

JoVE Journal

Bioengineering

10.8K 次观看.  University of Texas Health Science Center at Houston. 我们提出如何利用高通量低温电子断层扫描，以确定高分辨率的分子机器的结构原位的协议。该协议允许大量数据要处理，避免了常见的瓶颈，并减少停机时间资源，从而允许用户集中在重要的生物的问题。 

视频: Using Tomoauto: A Protocol for High-throughput Automated Cryo-electron Tomography

Polymer Microarrays for High Throughput Discovery of Biomaterials

The discovery of novel biomaterials that are optimized for a specific biological application is readily achieved using polymer microarrays, which allows a combinatorial library of materials to be screened in a parallel, high throughput format1. Herein is described the formation and characterization of a polymer microarray using an on-chip photopolymerization technique 2. This involves mixing monomers at varied ratios to produce a library of monomer solutions, transferring the solution to a glass slide format using a robotic printing device and curing with UV irradiation. This format is readily amenable to many biological assays, including stem cell attachment and proliferation, cell sorting and low bacterial adhesion, allowing the ready identification of 'hit' materials that fulfill a specific biological criterion3-5. Furthermore, the use of high throughput surface characterization (HTSC) allows the biological performance to be correlated with physio-chemical properties, hence elucidating the biological-material interaction6. HTSC makes use of water contact angle (WCA) measurements, atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). In particular, ToF-SIMS provides a chemically rich analysis of the sample that can be used to correlate the cell response with a molecular moiety. In some cases, the biological performance can be predicted from the ToF-SIMS spectra, demonstrating the chemical dependence of a biological-material interaction, and informing the development of hit materials5,3.

A description of the formation of a polymer microarray using an on-chip photopolymerization technique. The high throughput surface characterization using atomic force microscopy, water contact angle measurements, X-ray photoelectron spectroscopy and time of flight secondary ion mass spectrometry and a cell attachment assay is also described.

聚合物芯片高通量发现的生物材料

The discovery of novel biomaterials that are optimized for a specific biological application is readily achieved using polymer microarrays, which allows a ...

科研

生物工程

High-throughput Protein Expression Generator Using a Microfluidic Platform

Rapidly increasing fields, such as systems biology, require the development and implementation of new technologies, enabling high-throughput and high-fidelity measurements of large systems. Microfluidics promises to fulfill many of these requirements, such as performing high-throughput screening experiments on-chip, encompassing biochemical, biophysical, and cell-based assays1. Since the early days of microfluidics devices, this field has drastically evolved, leading to the development of microfluidic large-scale integration2,3. This technology allows for the integration of thousands of micromechanical valves on a single device with a postage-sized footprint (Figure 1). We have developed a high-throughput microfluidic platform for generating in vitro expression of protein arrays (Figure 2) named PING (Protein Interaction Network Generator). These arrays can serve as a template for many experiments such as protein-protein 4, protein-RNA5 or protein-DNA6 interactions.
The device consist of thousands of reaction chambers, which are individually programmed using a microarrayer. Aligning of these printed microarrays to microfluidics devices programs each chamber with a single spot eliminating potential contamination or cross-reactivity Moreover, generating microarrays using standard microarray spotting techniques is also very modular, allowing for the arraying of proteins7, DNA8, small molecules, and even colloidal suspensions. The potential impact of microfluidics on biological sciences is significant. A number of microfluidics based assays have already provided novel insights into the structure and function of biological systems, and the field of microfluidics will continue to impact biology.

We present a microfluidic approach for the expression of protein arrays. The device consists of thousands of reaction chambers controlled by micro-mechanical valves. The microfluidic device is mated to a microarray-printed gene library. These genes are then transcribed and translated on-chip, resulting in a protein array ready for experimental use.

利用微流控平台的高通量蛋白质表达发生器

Rapidly increasing fields, such as systems biology, require the development and implementation of new technologies, enabling high-throughput and ...

High-throughput, Automated Extraction of DNA and RNA from Clinical Samples using TruTip Technology on Common Liquid Handling Robots

TruTip is a simple nucleic acid extraction technology whereby a porous, monolithic binding matrix is inserted into a pipette tip. The geometry of the monolith can be adapted for specific pipette tips ranging in volume from 1.0 to 5.0 ml. The large porosity of the monolith enables viscous or complex samples to readily pass through it with minimal fluidic backpressure. Bi-directional flow maximizes residence time between the monolith and sample, and enables large sample volumes to be processed within a single TruTip. The fundamental steps, irrespective of sample volume or TruTip geometry, include cell lysis, nucleic acid binding to the inner pores of the TruTip monolith, washing away unbound sample components and lysis buffers, and eluting purified and concentrated nucleic acids into an appropriate buffer. The attributes and adaptability of TruTip are demonstrated in three automated clinical sample processing protocols using an Eppendorf epMotion 5070, Hamilton STAR and STARplus liquid handling robots, including RNA isolation from nasopharyngeal aspirate, genomic DNA isolation from whole blood, and fetal DNA extraction and enrichment from large volumes of maternal plasma (respectively).

TruTip is a simple nucleic acid extraction technology whereby a porous, monolithic binding matrix is inserted into a pipette tip. Consequently, the sample preparation format is compatible with most liquid handling instruments, and can be used for many medium to high-throughput clinical applications and sample types.

高通量，自动化的DNA和RNA的提取从临床样品使用TruTip技术常见的液体处理机器人

TruTip is a simple nucleic acid extraction  technology whereby a porous, monolithic binding matrix is inserted into a  pipette tip. The geometry of the ...

CometChip: A High-throughput 96-Well Platform for Measuring DNA Damage in Microarrayed Human Cells

DNA damaging agents can promote aging, disease and cancer and they are ubiquitous in the environment and produced within human cells as normal cellular metabolites. Ironically, at high doses DNA damaging agents are also used to treat cancer. The ability to quantify DNA damage responses is thus critical in the public health, pharmaceutical and clinical domains. Here, we describe a novel platform that exploits microfabrication techniques to pattern cells in a fixed microarray. The &#8216;CometChip&#8217; is based upon the well-established single cell gel electrophoresis assay (a.k.a. the comet assay), which estimates the level of DNA damage by evaluating the extent of DNA migration through a matrix in an electrical field. The type of damage measured by this assay includes abasic sites, crosslinks, and strand breaks. Instead of being randomly dispersed in agarose in the traditional assay, cells are captured into an agarose microwell array by gravity. The platform also expands from the size of a standard microscope slide to a 96-well format, enabling parallel processing. Here we describe the protocols of using the chip to evaluate DNA damage caused by known genotoxic agents and the cellular repair response followed after exposure. Through the integration of biological and engineering principles, this method potentiates robust and sensitive measurements of DNA damage in human cells and provides the necessary throughput for genotoxicity testing, drug development, epidemiological studies and clinical assays.

We describe here a platform that allows comet assay detection of DNA damage with unprecedented throughput. The device patterns mammalian cells into a microarray and enables parallel processing of 96 samples. The approach facilitates analysis of base level DNA damage, exposure-induced DNA damage and DNA repair kinetics.

CometChip:一种高通量的96孔平台的微阵列人类细胞测量DNA损伤

DNA damaging agents can promote aging, disease and cancer and they are ubiquitous in the environment and produced within human cells as normal cellular ...

A Microfluidic Platform for High-throughput Single-cell Isolation and Culture

Studying the heterogeneity of single cells is crucial for many biological questions, but is technically difficult. Thus, there is a need for a simple, yet high-throughput, method to perform single-cell culture experiments. Here, we report a microfluidic chip-based strategy for high-efficiency single-cell isolation (~77%) and demonstrate its capability of performing long-term single-cell culture (up to 7 d) and cellular heterogeneity analysis using clonogenic assay. These applications were demonstrated with KT98 mouse neural stem cells, and A549 and MDA-MB-435 human cancer cells. High single-cell isolation efficiency and long-term culture capability are achieved by using different sizes of microwells on the top and bottom of the microfluidic channel. The small microwell array is designed for precisely isolating single-cells, and the large microwell array is used for single-cell clonal culture in the microfluidic chip. This microfluidic platform constitutes an attractive approach for single-cell culture applications, due to its flexibility of adjustable cell culture spaces for different culture strategies, without decreasing isolation efficiency.

Here, we present a protocol for isolating and culturing single cells with a microfluidic platform, which utilizes a new microwell design concept to allow for high-efficiency single cell isolation and long-term clonal culture.

高通量单细胞的分离和文化的微流体平台

Studying the heterogeneity of single cells is crucial for many biological questions, but is technically difficult. Thus, there is a need for a simple, yet ...

Automated Lipid Bilayer Membrane Formation Using a Polydimethylsiloxane Thin Film

An artificial lipid bilayer, or black lipid membrane (BLM), is a powerful tool for studying ion channels and protein interactions, as well as for biosensor applications. However, conventional BLM formation techniques have several drawbacks and they often require specific expertise and laborious processes. In particular, conventional BLMs suffer from low formation success rates and inconsistent membrane formation time. Here, we demonstrate a storable and transportable BLM formation system with controlled thinning-out time and enhanced BLM formation rate by replacing conventionally used films (polytetrafluoroethylene, polyoxymethylene, polystyrene) to polydimethylsiloxane (PDMS). In this experiment, a porous-structured polymer such as PDMS thin film is used. In addition, as opposed to conventionally used solvents with low viscosity, the use of squalene permitted a controlled thinning-out time via slow solvent absorption by PDMS, prolonging membrane lifetime. In addition, by using a mixture of squalene and hexadecane, the freezing point of the lipid solution was increased (~16 &#176;C), in addition, membrane precursors were produced that can be indefinitely stored and readily transported. These membrane precursors have reduced BLM formation time of &#60; 1 hr and achieved a BLM formation rate of ~80%. Moreover, ion channel experiments with gramicidin A demonstrated the feasibility of the membrane system.

We demonstrate a storable, transportable lipid bilayer formation system. A lipid bilayer membrane can be formed within 1 hr with over 80% success rate when a frozen membrane precursor is brought to ambient temperature. This system will reduce laborious processes and expertise associated with ion channels.

自动化脂双层膜的形成使用聚二甲基硅氧烷薄膜

An artificial lipid bilayer, or black lipid membrane (BLM), is a powerful tool for studying ion channels and protein interactions, as well as for ...

High-throughput Identification of Bacteria Repellent Polymers for Medical Devices

Medical devices are often associated with hospital-acquired infections, which place enormous strain on patients and the healthcare system as well as contributing to antimicrobial resistance. One possible avenue for the reduction of device-associated infections is the identification of bacteria-repellent polymer coatings for these devices, which would prevent bacterial binding at the initial attachment step. A method for the identification of such repellent polymers, based on the parallel screening of hundreds of polymers using a microarray, is described here. This high-throughput method resulted in the identification of a range of promising polymers that resisted binding of various clinically relevant bacterial species individually and also as multi-species communities. One polymer, PA13 (poly(methylmethacrylate-co-dimethylacrylamide)), demonstrated significant reduction in attachment of a number of hospital isolates when coated onto two commercially available central venous catheters. The method described could be applied to identify polymers for a wide range of applications in which modification of bacterial attachment is important.

A high-throughput microarray method for the identification of polymers which reduce bacterial surface binding on medical devices is described.

医疗器械细菌高通量鉴定驱蚊聚合物

Medical devices are often associated with hospital-acquired infections, which place enormous strain on patients and the healthcare system as well as ...

Generic Protocol for Optimization of Heterologous Protein Production Using Automated Microbioreactor Technology

A core business in industrial biotechnology using microbial production cell factories is the iterative process of strain engineering and optimization of bioprocess conditions. One important aspect is the improvement of cultivation medium to provide an optimal environment for microbial formation of the product of interest. It is well accepted that the media composition can dramatically influence overall bioprocess performance. Nutrition medium optimization is known to improve recombinant protein production with microbial systems and thus, this is a rewarding step in bioprocess development. However, very often standard media recipes are taken from literature, since tailor-made design of the cultivation medium is a tedious task that demands microbioreactor technology for sufficient cultivation throughput, fast product analytics, as well as support by lab robotics to enable reliability in liquid handling steps. Furthermore, advanced mathematical methods are required for rationally analyzing measurement data and efficiently designing parallel experiments such as to achieve optimal information content.
The generic nature of the presented protocol allows for easy adaption to different lab equipment, other expression hosts, and target proteins of interest, as well as further bioprocess parameters. Moreover, other optimization objectives like protein production rate, specific yield, or product quality can be chosen to fit the scope of other optimization studies. The applied Kriging Toolbox (KriKit) is a general tool for Design of Experiments (DOE) that contributes to improved holistic bioprocess optimization. It also supports multi-objective optimization which can be important in optimizing both upstream and downstream processes.

This manuscript describes a generic approach for tailor-made design of microbial cultivation media. This is enabled by an iterative workflow combining Kriging-based experimental design and microbioreactor technology for sufficient cultivation throughput, which is supported by lab robotics to increase reliability and speed in liquid handling media preparation.

利用自动 Microbioreactor 技术优化异种蛋白质生产的通用协议

A core business in industrial biotechnology using microbial production cell factories is the iterative process of strain engineering and optimization of ...

Use of High-Throughput Automated Microbioreactor System for Production of Model IgG1 in CHO Cells

Automated microscale bioreactors (15 mL) can be a useful tool for cell culture engineers. They facilitate the simultaneous execution of a wide variety of experimental conditions while minimizing potential process variability. Applications of this approach include: clone screening, temperature and pH shifts,&#160;media and supplement optimization. Furthermore, the small reactor volumes are conducive to large Design of Experiments that investigate a wide range of conditions. This allows upstream processes to be significantly optimized before scale-up where experimentation is more limited in scope due to time and economic constraints. Automated microscale bioreactor systems offer various advantages over traditional small scale cell culture units, such as shake flasks or spinner flasks. However, during pilot scale process development&#160;significant care must be taken to ensure that these advantages are realized. When run with care, the system can enable high level automation, can be programmed to run DOE&#39;s with a higher number of variables&#160;and can reduce sampling time when integrated with a nutrient analyzer or cell counter. Integration of the expert-derived heuristics presented here, with current automated microscale bioreactor experiments can minimize common pitfalls that hinder meaningful results. In the extreme, failure to adhere to the principles laid out here can lead to equipment damage that requires expensive repairs. Furthermore, the microbioreactor systems have small culture volumes&#160;making characterization of cell culture conditions difficult. The number and amount of samples taken in-process in batch mode culture is limited as operating volumes cannot fall below 10 mL. This method will discuss the benefits and drawbacks of microscale bioreactor systems.

A detailed protocol for the concurrent operation of 48 parallel cell cultures under varied conditions in a microbioreactor system is presented. Cell culture process, harvest and subsequent antibody titer analysis are described.

高通量自动 Microbioreactor 系统在 CHO 细胞模型 IgG1 生产中的应用

Automated microscale bioreactors (15 mL) can be a useful tool for cell culture engineers. They facilitate the simultaneous execution of a wide variety of ...

Process Optimization using High Throughput Automated Micro-Bioreactors in Chinese Hamster Ovary Cell Cultivation

Optimization of bioprocesses to increase the yield of desired products is of importance in the biopharmaceutical industry. This can be achieved by strain selection and by developing bioprocess parameters. Shake flasks have been used for this purpose. They, however, lack the capability to control the process parameters such as pH and dissolved oxygen (DO). This limitation can be overcome with the help of an automated micro-bioreactor. These bioreactors mimic cultivation at a larger scale. One of the major advantages of this system is the integration of the Design of Experiment (DOE) in the software. This integration enables establishing a design where multiple process parameters can be varied simultaneously. The critical process parameters and optimum bioprocess conditions can be analyzed within the software. The focus of the work presented here is to introduce the user to the steps involved in process design in the software and incorporation of the DOE within the cultivation run.

Here, we present a detailed procedure to run a Design of Experiment in an automated micro-bioreactor followed by cell harvest and protein quantification using a Protein A column.

中国仓鼠卵巢细胞培养中高通量自动化微生物反应器工艺优化

Optimization of bioprocesses to increase the yield of desired products is of importance in the biopharmaceutical industry. This can be achieved by strain ...