Name: generation of in-frame gene deletion mutants in pseudomonas aeruginosa and testing for virulence attenuation in a simple mouse model of infection
Uploaded: 2020-01-08T14:00:00
Description: Watch this Scientific Journal Video about Generation of In-Frame Gene Deletion Mutants in Pseudomonas aeruginosa and Testing for Virulence Attenuation in a Simple Mouse Model of Infection at JoVE.com

这项工作得到了国家卫生研究院（NIH）授予R44GM113545和P20GM103434的支持。

在开始动物实验之前，要使用的协议必须获得机构动物护理和使用委员会 （IACUC） 的批准。通过马歇尔大学（美国加利福尼亚州亨廷顿）的IACUC获得了上述协议的批准。
1. 质粒设计
<ol><li>要使用pEX100T-NotI质粒生成遗传缺失，克隆DNA区域侧翼所需的删除序列，并插入质粒的NotI限制位点。质粒插入物应包含目标序列上游约500个核苷酸，直接与目标删除序列下游约500个核苷酸相?...

<ol>
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pEX100T-Not1 质粒是无标记和框架内连续基因组缺失的有效中介。当工程细菌菌株衰减毒性时，删除整个基因序列，而不是产生点突变，会减少回归到毒性表型的可能性。此外，每个致病基因缺失可进一步减轻病原体，增强衰减的稳定性。
此方法还可用于生成除了删除以外的基因组修饰，如点突变和插入，只需修改质粒插入的设计。例如，这些类型的修饰可能比整个基因删除对?...

假单核菌是一种机会性细菌病原体，可引起人类威胁生命的疾病，特别是在免疫功能低下。P. aeruginosa的致病性是由于许多毒性因素的表达，包括蛋白酶和脂多糖，以及它的能力，形成保护性生物膜1。由于其能够产生毒性因子和在人类中引起疾病，使用P.aeruginosa使商业产品存在安全问题。非致病性大肠杆菌菌株传统上用于生物工程医疗和商业产品供人类使用。然而，有些产品很难为大肠杆菌制造，而且许多产品被包装在内含物体中，使得提取费力。具有制造和分泌特定产品的工程细菌菌株是非常可取的，因为分泌可能会增加产量和简化纯化过程。因此，其他细菌种类的非致病菌株（例如，利用更多分泌途径的物种）可能为大肠杆菌提供有用的替代品。我们最近报道了P.aeruginosa，PGN5菌株的发展，其中生物体的致病性和毒性高度衰减2。重要的是，这种菌株仍然产生大量的多糖藻酸盐，这是P.aeruginosa生物膜中一种商业上有趣的成分。
PGN5菌株是使用pEX100T-NotI质粒的两步等位交换程序产生的，顺序删除五个已知有助于生物体的致病性的基因（毒体、plcH、phzM、wapR、aroA）。 pEX100T-NotI是在赫伯特·施韦泽的实验室3、4中开发的，通过将SmaI更改为TI限制酶识别位点，在质粒pEX100T的多个克隆位点内产生。与SmaI相比，限制性酶NotI的识别位点是一种罕见的DNA序列，在克隆序列中出现的可能性较小，因此更便于克隆。质粒携带允许选择的基因，包括bla基因，该基因编码β-乳糖酶，并产生对卡比西林的抗药性，B.subtilissacB基因，赋予蔗糖的敏感性（图1A）。质粒还带有与大肠杆菌相容的复制（ori）的来源，以及允许通过结合从大肠杆菌转移到伪多尼纳斯物种的转移（或或T）的来源。然而，质粒缺乏与伪多尼萨兼容的复制来源，因此无法在伪多尼纳斯物种中复制（即，它是一个伪多尼纳斯自杀载体）。这些特性使pEX100T-NotI成为定位从伪多尼纳斯染色体遗传缺失的理想选择。疟原虫克隆步骤使用大肠杆菌进行，由此产生的质粒通过转化或结合转移到伪多尼氏。然后，通过同源重组事件和选择性步骤，生成目标帧内删除，无标记。这种从P.aeruginosa染色体上按顺序删除基因组区域的方法可用于产生高度衰减的伪多尼纳斯菌株，如PGN5，或设计用于其他特定用途的菌株（例如，质粒繁殖的内分酶缺乏菌株或缺乏蛋白酶的菌株，用于生产感兴趣的蛋白质）。
细菌菌株的整体毒性受生长条件和阶段的影响，在此期间突变频繁发生。因此，测量基因工程菌株的安全性可能具有挑战性。为了评估细菌分离物的系统性毒性，我们采用了以前公布的C57BL/6小鼠腹内注射感染方案。我们修改了这个程序，使用冷冻细菌储存注射，这允许精确的给给和使用的菌株验证。在此模型中，经FDA批准生产生物制药的大肠杆菌菌株BL21被用作控制安全标准，用于确定该菌株6、7、8的相对发病机制。使用此方法的主要优点是，它是可重复的，并最大限度地减少变异源，因为感染菌株在感染之前和之后都验证细菌细胞数、表型和遗传标记。通过这些受控步骤，所需的动物数量会减少。在此模型中，导致C57BL/6小鼠死亡率等于或低于大肠杆菌BL21的P.aeruginosa菌株在注射腹内时可被视为衰减。这种简单的小鼠感染模型也可用于评估其他物种的遗传工程菌株的衰减致病性，以FDA批准的大肠杆菌菌株为参考。步骤1-7详细介绍了P.aeruginosa（图1）中连续基因组缺失的生成，步骤8-12详细介绍了使用小鼠模型来测试P.aeruginosa菌株的致病性。

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>0.2 mL tubes with flat caps</td>
			<td>ThermoScientific</td>
			<td>AB-0620</td>
			<td>via Fisher Scientific</td>
		</tr>
		<tr>
			<td>1 mL Syringe</td>
			<td>BD</td>
			<td>22-253-260</td>
			<td>via Fisher Scientific</td>
		</tr>
		<tr>
			<td>1.5 mL disposable polystyrene cuvette</td>
			<td>Fisher Scientific</td>
			<td>14955127</td>
			<td></td>
		</tr>
		<tr>
			<td>1.5 mL Microcentrifuge Tubes</td>
			<td>Fisher Scientific</td>
			<td>05-408-129</td>
			<td></td>
		</tr>
		<tr>
			<td>2.0 mL Cryogenic Vials</td>
			<td>Corning</td>
			<td>430659</td>
			<td>via Fisher Scientific</td>
		</tr>
		<tr>
			<td>27G needle</td>
			<td>BD</td>
			<td>14-821-13B</td>
			<td>via Fisher Scientific</td>
		</tr>
		<tr>
			<td>50 mL tubes</td>
			<td>Fisher Scientific</td>
			<td>05-539-13</td>
			<td>via Fisher Scientific</td>
		</tr>
		<tr>
			<td>Accu block Digital Dry Bath</td>
			<td>Labnet</td>
			<td>NC0205808</td>
			<td>via Fisher Scientific</td>
		</tr>
		<tr>
			<td>Benchtop Centrifuge 5804R</td>
			<td>Eppendorf</td>
			<td>04-987-372</td>
			<td>via Fisher Scientific</td>
		</tr>
		<tr>
			<td>Benchtop Microcentrifuge</td>
			<td>Sorvall</td>
			<td>75-003-287</td>
			<td>via Fisher Scientific</td>
		</tr>
		<tr>
			<td>Cabinet Incubator</td>
			<td>VWR</td>
			<td>1540</td>
			<td></td>
		</tr>
		<tr>
			<td>Carbenicillin disodium salt</td>
			<td>Fisher Scientific</td>
			<td>BP2648250</td>
			<td></td>
		</tr>
		<tr>
			<td>Culture Test Tube, Polystyrene</td>
			<td>Fisher Scientific</td>
			<td>14-956-6D</td>
			<td>via Fisher Scientific</td>
		</tr>
		<tr>
			<td>Diposable Inoculation Loops</td>
			<td>Fisher Scientific</td>
			<td>22-363-597</td>
			<td></td>
		</tr>
		<tr>
			<td>Dneasy UltraClean Microbial Kit (50)</td>
			<td>Qiagen</td>
			<td>12224-50</td>
			<td>or preferred method/vendor</td>
		</tr>
		<tr>
			<td>E.Z.N.A. Cycle Pure Kit (50)</td>
			<td>Omega bio-tek</td>
			<td>D6493-01</td>
			<td>or preferred method/vendor</td>
		</tr>
		<tr>
			<td>EcoRI-HF, restriction endonuclease</td>
			<td>New England BioLabs</td>
			<td>R3101L</td>
			<td></td>
		</tr>
		<tr>
			<td>Electroporation Cuvettes</td>
			<td>Bulldog Bio</td>
			<td>NC0492929</td>
			<td>via Fisher Scientific</td>
		</tr>
		<tr>
			<td>FastLink II DNA Ligation Kit</td>
			<td>Epicentre Technologies</td>
			<td>LK6201H</td>
			<td>via Fisher Scientific</td>
		</tr>
		<tr>
			<td>Gentamycin Sulfate</td>
			<td>Fisher Scientific</td>
			<td>BP918-1</td>
			<td></td>
		</tr>
		<tr>
			<td>Glycerol</td>
			<td>Fisher Scientific</td>
			<td>BP229-4</td>
			<td></td>
		</tr>
		<tr>
			<td>GoTaq G2 Colorless Master Mix</td>
			<td>Promega</td>
			<td>M7833</td>
			<td>via Fisher Scientific</td>
		</tr>
		<tr>
			<td>Isothesia Isoflurane</td>
			<td>Henry Schein Animal Health</td>
			<td>29405</td>
			<td></td>
		</tr>
		<tr>
			<td>IVIS Lumina XRMS Series III In Vivo Imaging System</td>
			<td>Perkins and Elmer</td>
			<td>CLS136340</td>
			<td></td>
		</tr>
		<tr>
			<td>Kanamycin monosulfate</td>
			<td>Fisher Scientific</td>
			<td>BP906-5</td>
			<td></td>
		</tr>
		<tr>
			<td>LE agarose</td>
			<td>Genemate</td>
			<td>3120-500</td>
			<td>via Fisher Scientific</td>
		</tr>
		<tr>
			<td>Luria Broth</td>
			<td>Difco</td>
			<td>240230</td>
			<td>via Fisher Scientific</td>
		</tr>
		<tr>
			<td>MicroPulser Electroporator</td>
			<td>BioRad</td>
			<td>1652100</td>
			<td></td>
		</tr>
		<tr>
			<td>Noble agar, ultrapure</td>
			<td>Affymetris/USB</td>
			<td>AAJ10907A1</td>
			<td>via Fisher Scientific</td>
		</tr>
		<tr>
			<td>NotI-HF, restriction endonuclease</td>
			<td>New England BioLabs</td>
			<td>R3189</td>
			<td></td>
		</tr>
		<tr>
			<td>One Shot TOP10 Electrocomp E. coli</td>
			<td>Invitrogen</td>
			<td>C404052</td>
			<td>via Fisher Scientific</td>
		</tr>
		<tr>
			<td>Phosphate buffered saline powder</td>
			<td>Sigma</td>
			<td>P3813-10PAK</td>
			<td>Sigma-Aldrich</td>
		</tr>
		<tr>
			<td>Prism 7</td>
			<td>GraphPad</td>
			<td></td>
			<td><a href="https://www.graphpad.com/scientific-software/prism/" target="_blank">https://www.graphpad.com/scientific-software/prism/</a></td>
		</tr>
		<tr>
			<td>Pseudomonas isolation agar</td>
			<td>Difco</td>
			<td>292710</td>
			<td>via Fisher Scientific</td>
		</tr>
		<tr>
			<td>Pseudomonas isolation broth</td>
			<td>Alpha Biosciences</td>
			<td>P16-115</td>
			<td>Custom made batch</td>
		</tr>
		<tr>
			<td>QIAprep Spin Miniprep Kit (250)</td>
			<td>Qiagen</td>
			<td>27106</td>
			<td>or preferred method/vendor</td>
		</tr>
		<tr>
			<td>Shaking Incubator</td>
			<td>New Brunswick Scientific</td>
			<td>Innova 4080</td>
			<td>shake at 200 rpm</td>
		</tr>
		<tr>
			<td>SimpliAmp Thermal Cycler</td>
			<td>Applied Biosystems</td>
			<td>A24811</td>
			<td></td>
		</tr>
		<tr>
			<td>Skim Milk</td>
			<td>Difco</td>
			<td>DF0032-17-3</td>
			<td>via Fisher Scientific</td>
		</tr>
		<tr>
			<td>Small Plates (100 O.D. x 10 mm)</td>
			<td>Fisher Scientific</td>
			<td>FB0875713</td>
			<td></td>
		</tr>
		<tr>
			<td>SmartSpec Plus Spectrophotometer</td>
			<td>Bio-Rad</td>
			<td>170-2525</td>
			<td>or preferred method/vendor</td>
		</tr>
		<tr>
			<td>Sucrose</td>
			<td>Fisher Scientific</td>
			<td>S5-500</td>
			<td></td>
		</tr>
		<tr>
			<td>Toothpicks, round</td>
			<td>Diamond</td>
			<td></td>
			<td>Any brand of toothpicks, autoclaved</td>
		</tr>
		<tr>
			<td>TOPO TA Cloning Kit, for seqeuncing</td>
			<td>Invitrogen</td>
			<td>45-0030</td>
			<td></td>
		</tr>
		<tr>
			<td>XAF-8 Anesthesia System Filters</td>
			<td>Perkins and Elmer</td>
			<td>118999</td>
			<td></td>
		</tr>
		<tr>
			<td>XGI 8 Gas Anesthesia System</td>
			<td>Caliper Life Sciences/Xenogen</td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

generation of in-frame gene deletion mutants in pseudomonas aeruginosa and testing for virulence attenuation in a simple mouse model of infection

微生物具有遗传多样性和多样性，已成为许多商业产品和生物制药的主要来源。虽然其中一些产品是有机体自然生产的，但其他产品需要生物体的遗传工程来提高产量。大肠杆菌的阿维性菌株历来是生产生物制药的首选细菌品种;然而，有些产品很难生产大肠杆菌。因此，其他细菌物种的阿维规则菌株可以为生产某些商业产品提供有用的替代品。假单抗是一种常见且经过深入研究的革兰氏阴性细菌，可提供大肠杆菌的合适替代品。然而，阿鲁吉诺萨是一种机会性人类病原体。在这里，我们详细介绍了一个程序，可用于通过使用pEX100T-NotI质粒通过顺序基因组删除来生成P.aeruginosa的非致病菌株。此方法的主要优点是产生无标记应变。该方法可用于生成用于生产商业产品的高衰减P. aeruginosa菌株，或为其他特定用途设计菌株。我们还描述了一个简单和可重复的小鼠模型细菌系统感染通过腹内注射经验证的测试菌株，以测试基因工程菌株的衰减相比，FDA批准的BL21菌株的大肠杆菌。

如图2所示，靶向基因组删除可以用具有特定引能的菌群PCR来确认，从而放大感兴趣的区域。与野生型菌落相比，携带基因组删除的菌落将产生较短的PCR波段大小。10-12个菌落的PCR屏幕通常足以检测至少一个带有目标删除的菌群。如果多次屏幕后未检测到删除操作，请从合并开始重复该过程。如果删除仍然失败，质粒插入可能需要通过测序确认，重新?...

Watch this Scientific Journal Video about Generation of In-Frame Gene Deletion Mutants in Pseudomonas aeruginosa and Testing for Virulence Attenuation in a Simple Mouse Model of Infection at JoVE.com

Generation of In-Frame Gene Deletion Mutants in Pseudomonas aeruginosa and Testing for Virulence Attenuation in a Simple Mouse Model of Infection

在这里，我们描述了一个简单和可重复的小鼠感染模型协议，以评估与美国食品和药物管理局（FDA）批准的大肠杆菌用于商业用途的假单抗病毒的遗传改性菌株的衰减。

在伪单体中生成帧内基因删除突变体，并在简单小鼠感染模型中测试病毒衰减

Microorganisms are genetically versatile and diverse and have become a major source of many commercial products and biopharmaceuticals. Though some of ...

该协议对于在伪多莫纳斯亚鲁吉诺萨的基因组中创建和确定心身所需的突变，以及测试突变对可重复小鼠模型中毒性降低的影响，具有十分重大意义。此技术的主要优点是铬验证和小鼠感染模型的可重复性。细菌在不断工作，不断变化。为了减慢此过程，我们使用冻结停止，袋他们，挂在多个运行修改，然后再测试他们在鼠标模型中。不熟悉这些方法的人很可能会与开发和选择可能的交叉重组测试斗争。此外，对于不熟悉动物工作的人来说，处理小鼠感染将是困难的。该方法可用于检测其他病原体及其突变体，以及小鼠的毒性感染。与目前的模型相比，具有可重复性的程序以及感染前和感染后克隆验证程序可使该领域的其他研究人员受益。此协议的可视化演示提供了对可能难以理解或仅通过阅读理解的广泛程序的见解。首先在伪单体隔离肉汤中生长单交叉、重组菌落或 PIB。将每种培养的 10 微升接种并条纹到预热的 PIA 板上，并辅以 10% 蔗糖。然后在37摄氏度下孵育板。第二天，从培养箱中取出盘子，检查它们的生长。耐蔗糖的菌落应该是双交叉重组剂。使用无菌牙签将至少 20 个菌落修补到 PIA 预热板上，PIA 辅以 10% 蔗糖，PIA 补充卡贝尼西林。孵育板过夜，并在第二天检查其生长。真正的双交叉重组剂对卡贝尼西林敏感，耐蔗糖。屏幕 10 到 20 个殖民地删除，使用殖民地 PCR。拿起一个疑似双交叉重组与无菌牙签的生长，并暂停它在50微升PBS。将悬浮液在100摄氏度下煮10分钟。在13，000次G下离心3分钟，然后放在冰上。然后，根据手稿指示执行 PCR。PCR 完成后，对产品执行阿加糖凝胶电泳。较小的放大产品表示已删除感兴趣区域的菌落。注射的早晨，在摄氏四度下解冻细菌细胞的低温，解冻三到四个小时。解冻后将小瓶放在冰上，并在两个小时内给老鼠注射。将每个冷冻的内热物转移到一个新的两毫升管中，并在4，500次G下离心10分钟。丢弃上一提液，将细胞颗粒重新悬浮在PBS的一毫升中。重复离心，将PBS中的细胞重新悬浮到每毫升形成单位的第九组，最终浓度为2.5倍10。从每种菌株的最终悬浮物中抽取三个样本，以验证浓度、基因型和表型。对于每种菌株，将1.5毫升的细胞悬浮液放入两毫升管中，并准备用于控制注射的PBS。将无菌动物手术室注射所需的小鼠和材料收集起来，并在开始前用消毒湿巾擦拭所有表面。戴上两副乳胶手套，以限制被刺的风险（如果被咬伤）以及实验室外套、安全眼镜和面罩。将鼠标从保持架上取下并称重，用永久标记标记尾部，用于注射后跟踪。用27针打开一个新的毫升注射器，并绘制200微升无菌PBS。用拇指和食指抓住耳朵后面的鼠标，捏捏，在颈部的尿布处形成皮肤褶皱。然后，用粉红色将尾巴固定到手掌中，使鼠标保持不动。以 30 度角将针头插入中线左侧或右侧的腹腔中。稍微抬起针头，确保针头不会插入器官。然后，慢慢注射PBS并取针。注射部位的螺栓是典型的。将针头放在指定的锐器处理容器中，然后将鼠标移到单独的保持架中。用下一只鼠标重复这个程序，注射一个笼子的所有小鼠后，将它们移回原来的笼子。注入对照组后，使用相同的过程注入测试组。完成所有注射后，将小鼠返回到住房室，然后用消毒湿巾清洁工作区。要对动物进行成像，请通过设置摄像机参数和加热舞台来准备成像系统。将氧气流量设置为每分钟 1.5 升，将异氟兰为 3.5%，然后将鼠标移到麻醉室，然后在麻醉后将鼠标移到温度稳定阶段。将鼠标放在其背部，伸出手臂，在成像过程中安装鼻锥，以管理 2.5%等值。关上门，拍摄小鼠的生物发光图像和X光。成像完成后，将鼠标返回到其保持架并监视它。它应该在三到五分钟内恢复知觉。目标基因组删除由殖民地PCR确认与特定的底因，放大了感兴趣的区域。与野生菌落相比，具有基因组缺失的菌落产生较短的PCR带。PGN 5的P aeruginosa的衰减菌株的内向注射导致0%的死亡率，相当于用大肠杆菌BL 21观察到的死亡率。然而，注射父应变对80%的小鼠是致命的。使用生物发光标记的父系和衰减菌株跟踪感染进展。衰减菌株在注射部位保持局部，直到生物发光褪色，这很可能与清除感染相吻合。该方法只检查了菌株产生的死亡率。更深入的免疫学和毒理学方面可用于确定感染的动态和感染的最终结果，不会导致死亡。过程中最重要的事情是进行广泛的验证，从初始鉴定到动物测试的各个步骤之间。缺少某些验证步骤可能会导致错误的结果，因为测试的菌株可能会发生突变和选择，或受到污染。随着这两种技术的发展，我们认为这将使我们的感染免疫学领域的研究人员更有效地研究强大的包相互作用如何导致极端的表型、败血症和死亡率。可以通过细菌的量分来比较不同营养素对变异的影响。

Research

JoVE Journal

Immunology and Infection

Generation of In-Frame Gene Deletion Mutants in Pseudomonas aeruginosa and Testing for Virulence Attenuation in a Simple Mouse Model of Infection

Pseudomonas aeruginosa and Saccharomyces cerevisiae Biofilm in Flow Cells

Pseudomonas aeruginosa and Saccharomyces cerevisiae Biofilm in Flow Cells

铜绿假单胞菌和酿酒酵母流细胞生物膜

Many microbial cells have the ability to form sessile microbial communities defined as biofilms that have altered physiological and pathological ...

科研

免疫与感染

Use of Artificial Sputum Medium to Test Antibiotic Efficacy Against Pseudomonas aeruginosa in Conditions More Relevant to the Cystic Fibrosis Lung

Use of Artificial Sputum Medium to Test Antibiotic Efficacy Against Pseudomonas aeruginosa in Conditions More Relevant to the Cystic Fibrosis Lung

使用人工痰介质测试抗生素药效试验<em&gt;绿脓杆菌</em&gt;更多相关的肺囊肿性纤维化的条件

There  is growing concern about the relevance of in vitro antimicrobial  susceptibility tests when applied to isolates of P. aeruginosa from  cystic ...

Long Term Chronic Pseudomonas aeruginosa Airway Infection in Mice

Long Term Chronic Pseudomonas aeruginosa Airway Infection in Mice

长期慢性<em&gt;铜绿假单胞菌</em&gt;在呼吸道感染小鼠

A mouse model of chronic airway infection is a key asset in cystic fibrosis (CF) research, although there are a number of concerns regarding the model ...

Pseudomonas aeruginosa Induced Lung Injury Model

Pseudomonas aeruginosa Induced Lung Injury Model

绿脓杆菌引起的肺损伤模型

In order to study human acute lung injury and pneumonia, it is important to develop animal models to mimic various pathological features of this disease. ...

Studying Microbial Communities In Vivo: A Model of Host-mediated Interaction Between Candida Albicans and Pseudomonas Aeruginosa in the Airways

Studying Microbial Communities In Vivo: A Model of Host-mediated Interaction Between Candida Albicans and Pseudomonas Aeruginosa in the Airways

研究微生物群落<em&gt;在体内</em&gt;：主机之间介互动的典范<em&gt;白色念珠菌</em&gt;和<em&gt;铜绿假单胞菌</em&gt;在航空

Studying host-pathogen interaction enables us to understand the underlying mechanisms of the pathogenicity during microbial infection. The prognosis of ...

A Simple and Efficient Approach to Construct Mutant Vaccinia Virus Vectors

一种简单有效的方法构建突变牛痘病毒载体

The CRISPR-associated endonuclease Cas9 can edit particular genomic loci directed by a single guide RNA (gRNA). The CRISPR/Cas9 system has been ...

Come to the Light Side: In Vivo Monitoring of Pseudomonas aeruginosa Biofilm Infections in Chronic Wounds in a Diabetic Hairless Murine Model

Come to the Light Side: In Vivo Monitoring of Pseudomonas aeruginosa Biofilm Infections in Chronic Wounds in a Diabetic Hairless Murine Model

来到光明的一面: 体内糖尿病无毛小鼠慢性伤口生物膜感染的监测

The presence of bacteria as structured biofilms in chronic wounds, especially in diabetic patients, is thought to prevent wound healing and resolution. ...

Replication of the Ordered, Nonredundant Library of Pseudomonas aeruginosa strain PA14 Transposon Insertion Mutants

Replication of the Ordered, Nonredundant Library of Pseudomonas aeruginosa strain PA14 Transposon Insertion Mutants

复制的有序, 非冗余图书馆的铜绿假单胞菌应变 PA14 座子插入突变体

Pseudomonas aeruginosa is a phenotypically and genotypically diverse and adaptable Gram-negative bacterium ubiquitous in human environments. P. aeruginosa ...

Evaluating Virulence and Pathogenesis of Aeromonas Infection in a Caenorhabditis elegans Model

Evaluating Virulence and Pathogenesis of Aeromonas Infection in a Caenorhabditis elegans Model

线虫模型中气单胞菌感染的毒力及发病机制评价

The human pathogen Aeromonas has been clinically shown to cause gastroenteritis, wound infections, septicemia, and urinary tract infections. Most human ...

A Delayed Inoculation Model of Chronic Pseudomonas aeruginosa Wound Infection

A Delayed Inoculation Model of Chronic Pseudomonas aeruginosa Wound Infection

慢性假单位病伤口感染的延迟接种模型

Pseudomonas aeruginosa (P. aeruginosa) is a major nosocomial pathogen of increasing relevance to human health and disease, particularly in the setting of ...