I would like to acknowledge Dr. Thomas Rademacher for providing the transgenic tobacco seeds and Ibrahim Al Amedi for cultivating the tobacco plants. I wish to thank Dr. Richard M Twyman for editorial assistance and Prof. Dr. Rainer Fischer for fruitful discussions. This work was funded in part by the European Research Council Advanced Grant ''Future-Pharma'', proposal number 269110, the Fraunhofer-Zukunftsstiftung (Fraunhofer Future Foundation) and the Fraunhofer-Gesellschaft Internal Programs under Grant No. Attract 125-600164.

<ol>
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Der Autor hat keinerlei Interessenkonflikte offen zu legen.

Der wichtigste Aspekt zu berücksichtigen , wenn eine DoE Einrichtung Partikel Flockung zu charakterisieren , ist , dass das Design grundsätzlich in der Lage sein müssen , um die zu erwartenden oder möglichen Auswirkungen 36,38, zB der Einfluss von pH - Wert, Polymertyp und Polymerkonzentration 16 erfassen und zu beschreiben. Daher ist es wichtig, den Anteil des Bauraums (FDS) vor Beginn der eigentlichen Experimente zu bewerten. Die FDS ist der Anteil des mehrdimensionalen Versuchsraum ...

Pflanzen sind weit verbreitet zu produzieren Nahrungsmittelrohstoffe wie Fruchtsäfte verwendet, aber sie können auch als Plattform für die Herstellung von höherwertigen biopharmazeutischen Produkten 1-3 entwickelt werden. In beiden Fällen wird der Weiterverarbeitung (DSP) beginnt häufig mit der Entnahme von Flüssigkeiten aus dem Gewebe wie Blätter oder Früchte, gefolgt von der Klärung der partikelbeladenen Extrakte 4,5. Für die Herstellung von Biopharmazeutika, können die Kosten für die DSP machen bis zu 80% der gesamten Produktionskosten 6,7 und dies spiegelt teilweise die hohe Partikelbelastung in Extrakten durch disruptive Methoden wie Blade-basierte Homogenisierung hergestellt 8,9 . Obwohl die rationale Auswahl der Filterschichten kann die Partikelgrößenverteilung in dem Extrakt auf Filterkapazität zu erhöhen und die Kosten 10,11 reduzieren, kann die Verbesserung nicht durch die Anzahl von Partikeln definiert , die Obergrenze der absolute Kapazität überschreiten , die pro aufbewahrt werden müssenEinheit Filterfläche Klärung zu erreichen. Die Decke kann aufgehoben werden , wenn weniger Partikel die Oberfläche der feinsten Filter in der Filterstrang gelangen, und dies kann , wenn dispergierte Teilchen vermischt sind mit Polymeren als Flockungsmittel bekannt , erreicht werden, die die Aggregation fördern 12 große Flocken zu bilden. Solche Flocken können weiter stromaufwärts durch gröbere und weniger teuer Beutelfilter zurückgehalten werden, um die Partikelbelastung Verringerung der feineren erreichen und teurer Tiefenfilter. Die Polymere müssen Sicherheitsprofile haben für ihre Anwendungen, zB für Biopharmazeutika sie mit der guten Herstellungspraxis (GMP) entsprechen müssen, und in der Regel müssen sie eine Molmasse&gt; 100 kDa haben und entweder neutral oder 13 aufgeladen werden kann. Während neutral Flockungsmittel deren Aggregation und die Bildung von Flocken mit einem Durchmesser handeln , im allgemeinen durch Vernetzung dispergierten Teilchen verursacht&gt; 1 mm 11, neutralisieren geladene Polymere die Ladung von dispersed Partikel, wodurch ihre Löslichkeit und damit verursachenden Niederschläge 14. Flockung kann durch Einstellen Parameter wie pH oder Leitfähigkeit und der Polymertyp oder der Konzentration verbessert werden, 15,16 , die Eigenschaften des Extrakts zu entsprechen. Tabakextrakte vorbehandelt mit 0,5-5,0 g L -1 Polyethylenimin (PEI), eine mehr als 2-fache Erhöhung der Tiefenfilterkapazität wurde in einer 100-L Pilotmaßstab Prozess berichtet. Die Kosten für dieses Polymers weniger als 10 € kg -1 , so dass ihre Einführung in den Prozess zu Kosteneinsparungen geführt von ca. 6.000 € für Filter und Verbrauchsmaterialien pro Charge 16 oder sogar noch mehr , wenn sie mit Cellulosebasis Filterhilfsmittel 17 kombiniert. Trotzdem sind Vorhersagemodelle erforderlich , um die a priori wirtschaftlichen Nutzen von Flockungsmitteln zu bewerten , da die Einbeziehung halten Schritten von 15-30 min 16,18 erfordern kann, was zu einer weiteren Investitionskosten für die LagerungPanzer. Es gibt jedoch noch keine mechanistische Modelle zur Verfügung, um das Ergebnis dieser Experimente aufgrund der komplexen Natur der Flockung vorhersagen kann. Daher ist ein geeignetes Design-of-Experiments (DoE) Ansatz 19 wurde wie in diesem Artikel beschrieben entwickelt. Ein Protokoll für die allgemeine DoE Verfahren wurde kürzlich 20 veröffentlicht. Kleines Geräte sind ab sofort verfügbar für das Hochdurchsatz - Screening von Flockungsbedingungen 21. Jedoch können diese Vorrichtungen nicht realistisch Bedingungen während der Ausflockung von Pflanzen simulieren extrahiert, da die Abmessungen des Reaktionsgefäßes (~ 7 mm für die Vertiefungen auf einer Platte mit 96 Vertiefungen) und die Partikel oder Flocken kann weniger als eine Größenordnung auseinander. Dies kann Mischmuster beeinflussen und damit die Vorhersagekraft des Modells. Darüber hinaus kann es schwierig sein, Prozesse zu verringern Präzipitation denen aufgrund nicht-linearen Änderungen des Mischungsverhalten und Präzipitat stabilität 22. Daher beschreibt dieser Artikel eine Bank-top-Skala - Screening - System mit einem Durchsatz von 50 bis 75 Proben pro Tag, Ergebnisse liefert , die von der anfänglichen 20 ml Reaktionsvolumen auf einer 100 l - Pilotmaßstab Prozess 16 skalierbar sind. Wenn es mit einem DoE Ansatz kombiniert, ermöglicht dies die Vorhersagemodelle für die Prozessoptimierung und Dokumentation im Rahmen eines Qualitäts-by-Design-Konzept verwendet werden. Das nachfolgend beschriebene Verfahren kann auch auf Biopharmazeutika angepasst werden produziert in der Zellkultur-basierten Verfahren, bei denen Flockungsmittel auch als kostensparende Werkzeug 23 in Betracht gezogen werden. Es kann auch die Ausfällung von Zielproteinen aus einem Rohextrakt zu modellieren als Teil eines Reinigungsstrategie verwendet werden, wie für die β-Glucuronidase in Raps, Mais und Soja 24,25 hergestellt demonstriert. Eine detaillierte Beschreibung der Flockungsmittel Eigenschaften können an anderer Stelle werden 16,26 und es ist wichtig , um sicherzustellen , dass das Polymer Konzentr gefundentionen sind entweder nicht-toxische oder unter schädlichen Mengen im Endprodukt 11.

<table border="0" cellpadding="0" cellspacing="0" width="946">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">2100P Portable Turbidimeter</td>
			<td style="width:195px;">Hach</td>
			<td style="width:119px;">4650000</td>
			<td style="width:272px;">Turbidimeter</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">2G12 antibody</td>
			<td style="width:195px;">Polymun</td>
			<td style="width:119px;">AB002</td>
			<td>Reference antibody</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">Biacore T200</td>
			<td style="width:195px;">GE Healthcare</td>
			<td style="width:119px;">28-9750-01</td>
			<td>SPR device</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">BP-410</td>
			<td style="width:195px;">Furh</td>
			<td style="width:119px;">2632410001</td>
			<td>Bag filter</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">Catiofast VSH</td>
			<td style="width:195px;">BASF</td>
			<td style="width:119px;">79002360</td>
			<td>Flocculating agent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">Centrifuge 5415D</td>
			<td style="width:195px;">Eppendorf</td>
			<td style="width:119px;">5424 000.410</td>
			<td>Centrifuge</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">Centrifuge tube 15 mL</td>
			<td style="width:195px;">Labomedic</td>
			<td style="width:119px;">2017106</td>
			<td>Reaction tube</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">Centrifuge tube 50 mL self-standing</td>
			<td style="width:195px;">Labomedic</td>
			<td style="width:119px;">1110504</td>
			<td>Reaction tube</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">Chitosan</td>
			<td style="width:195px;">Carl Roth GmbH</td>
			<td style="width:119px;">5375.1</td>
			<td>Flocculating agent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">Design-Expert(R) 8</td>
			<td style="width:195px;">Stat-Ease, Inc.</td>
			<td style="width:119px;">n.a.</td>
			<td>DoE software</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">Disodium phosphate</td>
			<td style="width:195px;">Carl Roth GmbH</td>
			<td style="width:119px;">&#160;4984.3&#160;</td>
			<td>Media component</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">Ferty 2 Mega</td>
			<td style="width:195px;">Kammlott</td>
			<td style="width:119px;">5.220072</td>
			<td>Fertilizer</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">Forma -86C ULT freezer</td>
			<td style="width:195px;">ThermoFisher</td>
			<td style="width:119px;">88400</td>
			<td>Freezer</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">Greenhouse</td>
			<td style="width:195px;">n.a.</td>
			<td style="width:119px;">n.a.</td>
			<td>For plant cultivation</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">Grodan Rockwool Cubes 10x10cm</td>
			<td style="width:195px;">Grodan</td>
			<td style="width:119px;">102446</td>
			<td>Rockwool block</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">HEPES</td>
			<td style="width:195px;">Carl Roth GmbH</td>
			<td style="width:119px;">9105.3</td>
			<td>Media component</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">K700P 60D</td>
			<td style="width:195px;">Pall</td>
			<td style="width:119px;">5302305</td>
			<td>Depth filter layer</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">KS50P 60D</td>
			<td style="width:195px;">Pall</td>
			<td style="width:119px;">B12486</td>
			<td>Depth filter layer</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">Miracloth</td>
			<td style="width:195px;">Labomedic</td>
			<td style="width:119px;">475855-1R</td>
			<td>Filter cloth</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">MultiLine Multi 3410 IDS</td>
			<td style="width:195px;">WTW</td>
			<td style="width:119px;">WTW_2020</td>
			<td>pH meter / conductivity meter</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">Osram cool white 36 W</td>
			<td style="width:195px;">Osram</td>
			<td style="width:119px;">4930440</td>
			<td>Light source</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">Phytotron</td>
			<td style="width:195px;">Ilka Zell</td>
			<td style="width:119px;">n.a.</td>
			<td>For plant cultivation</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">Polymin P</td>
			<td style="width:195px;">BASF</td>
			<td style="width:119px;">79002360</td>
			<td>Flocculating agent</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">POLYTRON PT 6100 D</td>
			<td style="width:195px;">Kinematica</td>
			<td style="width:119px;">11010110</td>
			<td>Homogenization device with custom blade tool</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">Protein A</td>
			<td style="width:195px;">Life technologies</td>
			<td style="width:119px;">10-1006</td>
			<td>Antibody binding protein</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">Sodium chloride</td>
			<td style="width:195px;">Carl Roth GmbH</td>
			<td style="width:119px;">P029.2</td>
			<td>Media component</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">Synergy HT</td>
			<td style="width:195px;">BioTek</td>
			<td style="width:119px;">SIAFRT</td>
			<td>Fluorescence plate reader</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">TRIS</td>
			<td style="width:195px;">Carl Roth GmbH</td>
			<td style="width:119px;">4855.3</td>
			<td>Media component</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">Tween-20</td>
			<td style="width:195px;">Carl Roth GmbH</td>
			<td style="width:119px;">9127.3</td>
			<td>Media component</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">VelaPad 60</td>
			<td style="width:195px;">Pall</td>
			<td style="width:119px;">VP60G03KNH4</td>
			<td>Filter housing</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:360px;">Zetasizer Nano ZS</td>
			<td style="width:195px;">Malvern</td>
			<td style="width:119px;">ZEN3600</td>
			<td>DLS particle size distribution measurement</td>
		</tr>
	</tbody>
</table>

procedure to evaluate the efficiency of flocculants for the removal of dispersed particles from plant extracts

Plants are important to humans not only because they provide commodities such as food, feed and raw materials, but increasingly because they can be used as manufacturing platforms for added-value products such as biopharmaceuticals. In both cases, liquid plant extracts may need to be clarified to remove particulates. Optimal clarification reduces the costs of filtration and centrifugation by increasing capacity and longevity. This can be achieved by introducing charged polymers known as flocculants, which cross-link dispersed particles to facilitate solid-liquid separation. There are no mechanistic flocculation models for complex mixtures such as plant extracts so empirical models are used instead. Here a design-of-experiments procedure is described that allows the rapid screening of different flocculants, optimizing the clarification of plant extracts and significantly reducing turbidity. The resulting predictive models allow the identification of robust process conditions and sets of polymers with complementary properties, e.g. effective flocculation in extracts with specific conductivities. The results presented for tobacco leaf extracts can easily be adapted to other plant species or tissues and will thus facilitate the development of more cost-effective downstream processes for commodities and plant-derived pharmaceuticals.

Flockung von Tabakextrakt mit verschiedenen Polymeren Das oben beschriebene Verfahren wurde erfolgreich ein Verfahren zu entwickeln für die Ausflockung von Tabakextrakte bei der Herstellung eines monoklonalen Antikörpers (der HIV-neutralisierenden Antikörper 2G12) und ein fluoreszierendes Protein (DsRed) (Abbildung 1) 16 verwendet und ist seit übertragen auf andere Proteine ​​einschließlich...

Watch this Scientific Journal Video about Procedure to Evaluate the Efficiency of Flocculants for the Removal of Dispersed Particles from Plant Extracts at JoVE.com

Procedure to Evaluate the Efficiency of Flocculants for the Removal of Dispersed Particles from Plant Extracts

The design-of-experiments procedure presented here allows the evaluation of different flocculants in terms of their ability to aggregate dispersed particles in plant extracts, thus reducing turbidity and the costs of downstream processing.

Vorgehensweise Um die Effizienz von Flockungsmittel für die Beseitigung von Dispersed Partikel aus Pflanzenextrakten zur Bewertung

Plants are important to humans not only because they provide commodities such as food, feed and raw materials, but increasingly because they can be used ...

procedure-to-evaluate-efficiency-flocculants-for-removal-dispersed

Research

JoVE Journal

Biology

8.8K Aufrufe.  Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e. V.. The design-of-experiments procedure presented here allows the evaluation of different flocculants in terms of their ability to aggregate dispersed particles in plant extracts, thus reducing turbidity and the costs of downstream processing.

Serie: Procedure to Evaluate the Efficiency of Flocculants for the Removal of Dispersed Particles from Plant Extracts

Choice and No-Choice Assays for Testing the Resistance of A. thaliana to Chewing Insects

Larvae of the small white cabbage butterfly are a pest in agricultural settings. This caterpillar species feeds from plants in the cabbage family, which include many crops such as cabbage, broccoli, Brussel sprouts etc. Rearing of the insects takes place on cabbage plants in the greenhouse. At least two cages are needed for the rearing of Pieris rapae. One for the larvae and the other to contain the adults, the butterflies. In order to investigate the role of plant hormones and toxic plant chemicals in resistance to this insect pest, we demonstrate two experiments. First, determination of the role of jasmonic acid (JA - a plant hormone often indicated in resistance to insects) in resistance to the chewing insect Pieris rapae. Caterpillar growth can be compared on wild-type and mutant plants impaired in production of JA. This experiment is considered "No Choice", because larvae are forced to subsist on a single plant which synthesizes or is deficient in JA. Second, we demonstrate an experiment that investigates the role of glucosinolates, which are used as oviposition (egg-laying) signals. Here, we use WT and mutant Arabidopsis impaired in glucosinolate production in a "Choice" experiment in which female butterflies are allowed to choose to lay their eggs on plants of either genotype. This video demonstrates the experimental setup for both assays as well as representative results.

Plant resistance to chewing insect herbivores can be tested in several ways. Here, we demonstrate how to set-up a choice and a no-choice experiment with the model plant Arabidopsis thaliana to identify resistance against the pest species Pieris rapae.

Auswahl und No-Choice Tests zur Prüfung der Beständigkeit von A. thaliana zu Fraßinsekten

Larvae of the small white cabbage butterfly are a pest in agricultural settings. This caterpillar species feeds from plants in the cabbage family, which ...

Forschung

Biologie

Testing the Physiological Barriers to Viral Transmission in Aphids Using Microinjection

Potato loafroll virus (PLRV), from the family Luteoviridae infects solanaceous plants. It is transmitted by aphids, primarily, the green peach aphid. When an uninfected aphid feeds on an infected plant it contracts the virus through the plant phloem. Once ingested, the virus must pass from the insect gut to the hemolymph (the insect  blood ) and then must pass through the salivary gland, in order to be transmitted back to a new plant. An aphid may take up different viruses when munching on a plant, however only a small fraction will pass through the gut and salivary gland, the two main barriers for transmission to infect more plants. In the lab, we use physalis plants to study PLRV transmission. In this host, symptoms are characterized by stunting and interveinal chlorosis (yellowing of the leaves between the veins with the veins remaining green). The video that we present demonstrates a method for performing aphid microinjection on insects that do not vector PLVR viruses and tests whether the gut is preventing viral transmission.
The video that we present demonstrates a method for performing Aphid microinjection on insects that do not vector PLVR viruses and tests whether the gut or salivary gland is preventing viral transmission.

Aphids are effective transmitters of plant viruses. Aphid microinjection of virus, the procedure we will show you today, is a technique allowing researchers to inject virus directly into the hemocoel of the aphid, bypassing the gut, one of the 2 major barriers for virus transmission in a circulative manner. The same technique is also used to inject dsRNA for RNAi.

Testen der physiologische Barrieren für die virale Transmission in Blattläuse mit Mikroinjektion

Potato loafroll virus (PLRV), from the family Luteoviridae infects solanaceous plants. It is transmitted by aphids, primarily, the green peach aphid. When ...

Murine Renal Transplantation Procedure

Renal orthotopic transplantation in mice is a technically challenging procedure. Although the first kidney transplants in mice were performed by Russell et al over 30 years ago (1) and refined by Zhang et al years later (2), few people in the world have mastered this procedure. In our laboratory we have successfully performed 1200 orthotopic kidney transplantations with &gt; 90% survival rate. The key points for success include stringent control of reperfusion injury, bleeding and thrombosis, both during the procedure and post-transplantation, and use of 10-0 instead of 11-0 suture for anastomoses.
Post-operative care and treatment of the recipient is extremely important to transplant success and evaluation. All renal graft recipients receive antibiotics in the form of an injection of penicillin immediately post-transplant and sulfatrim in the drinking water continually. Overall animal health is evaluated daily and whole blood creatinine analyses are performed routinely with a portable I-STAT machine to assess graft function.

Renal transplantation in mice is a technically challenging procedure that requires careful post-operative care and treatment for success.

Murine Renal Transplantation

Renal orthotopic transplantation in mice is a technically challenging procedure. Although the first kidney transplants in mice were performed by Russell ...

A PCR-based Genotyping Method to Distinguish Between Wild-type and Ornamental Varieties of Imperata cylindrica

Wild-type I. cylindrica (cogongrass) is one of the top ten worst invasive plants in the world, negatively impacting agricultural and natural resources in 73 different countries throughout Africa, Asia, Europe, New Zealand, Oceania and the Americas1-2. Cogongrass forms rapidly-spreading, monodominant stands that displace a large variety of native plant species and in turn threaten the native animals that depend on the displaced native plant species for forage and shelter. To add to the problem, an ornamental variety [I. cylindrica var. koenigii (Retzius)] is widely marketed under the names of Imperata cylindrica 'Rubra', Red Baron, and Japanese blood grass (JBG). This variety is putatively sterile and noninvasive and is considered a desirable ornamental for its red-colored leaves. However, under the correct conditions, JBG can produce viable seed (Carol Holko, 2009 personal communication) and can revert to a green invasive form that is often indistinguishable from cogongrass as it takes on the distinguishing characteristics of the wild-type invasive variety4 (Figure 1). This makes identification using morphology a difficult task even for well-trained plant taxonomists. Reversion of JBG to an aggressive green phenotype is also not a rare occurrence. Using sequence comparisons of coding and variable regions in both nuclear and chloroplast DNA, we have confirmed that JBG has reverted to the green invasive within the states of Maryland, South Carolina, and Missouri. JBG has been sold and planted in just about every state in the continental U.S. where there is not an active cogongrass infestation. The extent of the revert problem in not well understood because reverted plants are undocumented and often destroyed.
Application of this molecular protocol provides a method to identify JBG reverts and can help keep these varieties from co-occurring and possibly hybridizing. Cogongrass is an obligate outcrosser and, when crossed with a different genotype, can produce viable wind-dispersed seeds that spread cogongrass over wide distances5-7. JBG has a slightly different genotype than cogongrass and may be able to form viable hybrids with cogongrass. To add to the problem, JBG is more cold and shade tolerant than cogongrass8-10, and gene flow between these two varieties is likely to generate hybrids that are more aggressive, shade tolerant, and cold hardy than wild-type cogongrass. While wild-type cogongrass currently infests over 490 million hectares worldwide, in the Southeast U.S. it infests over 500,000 hectares and is capable of occupying most of the U.S. as it rapidly spreads northward due to its broad niche and geographic potential3,7,11. The potential of a genetic crossing is a serious concern for the USDA-APHIS Federal Noxious Week Program. Currently, the USDA-APHIS prohibits JBG in states where there are major cogongrass infestations (e.g., Florida, Alabama, Mississippi). However, preventing the two varieties from combining can prove more difficult as cogongrass and JBG expand their distributions. Furthermore, the distribution of the JBG revert is currently unknown and without the ability to identify these varieties through morphology, some cogongrass infestations may be the result of JBG reverts. Unfortunately, current molecular methods of identification typically rely on AFLP (Amplified Fragment Length Polymorphisms) and DNA sequencing, both of which are time consuming and costly. Here, we present the first cost-effective and reliable PCR-based molecular genotyping method to accurately distinguish between cogongrass and JBG revert.

A PCR-based Genotyping Method to Distinguish Between Wild-type and Ornamental Varieties of Imperata cylindrica

We provide a cost-effective and rapid molecular genotyping protocol that employs variety-specific PCR primers that target DNA sequence differences within the chloroplast trnL-F spacer region to differentiate between varieties of Imperata cylindrica (cogongrass) that cannot be distinguished by morphology alone. These varieties include the federally listed noxious weed, cogongrass and closely-related, wide-spread ornamental variety, I. cylindrica var. koenigii (Japanese blood grass).

Ein PCR-basierte Genotypisierung Methode, zwischen Wildtyp-und Ziersorten Unterscheiden von Imperata cylindrica</em

Wild-type I. cylindrica (cogongrass) is one of the top ten worst invasive plants in the world, negatively impacting agricultural and natural resources in ...

Isolation of Viable Multicellular Glands from Tissue of the Carnivorous Plant, Nepenthes

Many plants possess specialized structures that are involved in the production and secretion of specific low molecular weight compounds and proteins. These structures are almost always localized on plant surfaces. Among them are nectaries or glandular trichomes. The secreted compounds are often employed in interactions with the biotic environment, for example as attractants for pollinators or deterrents against herbivores.
Glands that are unique in several aspects can be found in carnivorous plants. In so-called pitcher plants of the genus Nepenthes, bifunctional glands inside the pitfall-trap on the one hand secrete the digestive fluid, including all enzymes necessary for prey digestion, and on the other hand take-up the released nutrients. Thus, these glands represent an ideal, specialized tissue predestinated to study the underlying molecular, biochemical, and physiological mechanisms of protein secretion and nutrient uptake in plants. Moreover, generally the biosynthesis of secondary compounds produced by many plants equipped with glandular structures could be investigated directly in glands.
In order to work on such specialized structures, they need to be isolated efficiently, fast, metabolically active, and without contamination with other tissues. Therefore, a mechanical micropreparation technique was developed and applied for studies on Nepenthes digestion fluid. Here, a protocol is presented that was used to successfully prepare single bifunctional glands from Nepenthes traps, based on a mechanized microsampling platform. The glands could be isolated and directly used further for gene expression analysis by PCR techniques after preparation of RNA.

Isolation of Viable Multicellular Glands from Tissue of the Carnivorous Plant, Nepenthes

Plants glands are specialized structures responsible for the biosynthesis and secretion of many compounds involved in interactions with the biotic environment. To enable studies on their molecular and biochemical features, a mechanical micropreparation technique was established in order to isolate single metabolically active glands, here from the carnivorous plant Nepenthes.

Many plants possess specialized structures that are involved in the production and secretion of specific low molecular weight compounds and proteins. ...

Identification of Post-translational Modifications of Plant Protein Complexes

Plants adapt quickly to changing environments due to elaborate perception and signaling systems. During pathogen attack, plants rapidly respond to infection via the recruitment and activation of immune complexes. Activation of immune complexes is associated with post-translational modifications (PTMs) of proteins, such as phosphorylation, glycosylation, or ubiquitination. Understanding how these PTMs are choreographed will lead to a better understanding of how resistance is achieved.
Here we describe a protein purification method for nucleotide-binding leucine-rich repeat (NB-LRR)-interacting proteins and the subsequent identification of their post-translational modifications (PTMs). With small modifications, the protocol can be applied for the purification of other plant protein complexes. The method is based on the expression of an epitope-tagged version of the protein of interest, which is subsequently partially purified by immunoprecipitation and subjected to mass spectrometry for identification of interacting proteins and PTMs.
This protocol demonstrates that: i). Dynamic changes in PTMs such as phosphorylation can be detected by mass spectrometry; ii). It is important to have sufficient quantities of the protein of interest, and this can compensate for the lack of purity of the immunoprecipitate; iii). In order to detect PTMs of a protein of interest, this protein has to be immunoprecipitated to get a sufficient quantity of protein.

We describe here a protocol for the purification and characterization of plant protein complexes. We demonstrate that by immunoprecipitating a single protein within a complex, so we can identify its post-translational modifications and its interacting partners.

Bezeichnung des Post-translationale Modifikationen von Pflanzenproteinkomplexe

Plants adapt quickly to changing environments due to elaborate perception and signaling systems. During pathogen attack, plants rapidly respond to ...

In Vitro Pancreas Organogenesis from Dispersed Mouse Embryonic Progenitors

The pancreas is an essential organ that regulates glucose homeostasis and secretes digestive enzymes. Research on pancreas embryogenesis has led to the development of protocols to produce pancreatic cells from stem cells 1. The whole embryonic organ can be cultured at multiple stages of development 2-4. These culture methods have been useful to test drugs and to image developmental processes. However the expansion of the organ is very limited and morphogenesis is not faithfully recapitulated since the organ flattens. 
We propose three-dimensional (3D) culture conditions that enable the efficient expansion of dissociated mouse embryonic pancreatic progenitors. By manipulating the composition of the culture medium it is possible to generate either hollow spheres, mainly composed of pancreatic progenitors expanding in their initial state, or, complex organoids which progress to more mature expanding progenitors and differentiate into endocrine, acinar and ductal cells and which spontaneously self-organize to resemble the embryonic pancreas. 
We show here that the in vitro process recapitulates many aspects of natural pancreas development. This culture system is suitable to investigate how cells cooperate to form an organ by reducing its initial complexity to few progenitors. It is a model that reproduces the 3D architecture of the pancreas and that is therefore useful to study morphogenesis, including polarization of epithelial structures and branching. It is also appropriate to assess the response to mechanical cues of the niche such as stiffness and the effects on cell&#180;s tensegrity.

In Vitro Pancreas Organogenesis from Dispersed Mouse Embryonic Progenitors

The three-dimensional culture method described in this protocol recapitulates pancreas development from dispersed embryonic mouse pancreas progenitors, including their substantial expansion, differentiation and morphogenesis into a branched organ. This method is amenable to imaging, functional interference and manipulation of the niche.

In-vitro-Pankreas Organogenese von Dispersed embryonalen Maus-Vorläufer

The pancreas is an essential organ that regulates glucose homeostasis and secretes digestive enzymes. Research on pancreas embryogenesis has led to the ...

Imaging Spatial Reorganization of a MAPK Signaling Pathway Using the Tobacco Transient Expression System

Visualization of dynamic signaling events in live cells has been a challenge. We expanded an established transient expression system, the biomolecular fluorescent complementation (BiFC) assay in tobacco epidermal cells, from testing protein-protein interaction to monitoring spatial distribution of signal transduction in plant cells. In this protocol, we used the BiFC assay to show that the interaction and the signaling between the Arabidopsis MAPKKK YODA and MAPK6 occur at the plasma membrane. When the scaffold protein BASL was co-expressed, the YODA-MAPK interaction redistributed and spatially co-polarized with CFP-BASL. This modified tobacco expression system allows for quick examination of signaling localization and dynamic changes (less than 4 days) and can accommodate multiple of fluorescent protein colors (at least three). We also presented detailed methods to quantify protein distribution (asymmetric spatial localization, or &#34;polarization&#34;) in tobacco cells. This advanced tobacco expression system has a potential to be used widely for quick testing of dynamic signaling events in live plant cells.

At the subcellular level, signaling events are dynamically modulated by developmental and environmental cues. Here we describe a protocol that employs the tobacco transient expression system to monitor dynamic protein-protein interaction and to disclose spatial organization of signal transduction in plant cells.

Imaging Räumliche Reorganisation eines MAPK Signalweg Verwendung des Tabak Transient Expression System

Visualization of dynamic signaling events in live cells has been a challenge. We expanded an established transient expression system, the biomolecular ...

Removal of Exogenous Materials from the Outer Portion of Frozen Cores to Investigate the Ancient Biological Communities Harbored Inside

The cryosphere offers access to preserved organisms that persisted under past environmental conditions. In fact, these frozen materials could reflect conditions over vast time periods and investigation of biological materials harbored inside could provide insight of ancient environments. To appropriately analyze these ecosystems and extract meaningful biological information from frozen soils and ice, proper collection and processing of the frozen samples is necessary. This is especially critical for microbial and DNA analyses since the communities present may be so uniquely different from modern ones. Here, a protocol is presented to successfully collect and decontaminate frozen cores. Both the absence of the colonies used to dope the outer surface and exogenous DNA suggest that we successfully decontaminated the frozen cores and that the microorganisms detected were from the material, rather than contamination from drilling or processing the cores.

The cryosphere offers access to preserved organisms that persisted under past environmental conditions. A protocol is presented to collect and decontaminate permafrost cores of soils and ice. The absence of exogenous colonies and DNA suggest that microorganisms detected represent the material, rather than contamination from drilling or processing.

Entfernen von exogenen Materialien aus dem äußeren Teil der gefrorenen Kerne der Antike biologische Gemeinschaften beherbergte Innen zur Untersuchung

The cryosphere offers access to preserved organisms that persisted under past environmental conditions. In fact, these frozen materials could reflect ...

Comparison of Tobacco Host Cell Protein Removal Methods by Blanching Intact Plants or by Heat Treatment of Extracts

Plants not only provide food, feed and raw materials for humans, but have also been developed as an economical production system for biopharmaceutical proteins, such as antibodies, vaccine candidates and enzymes. These must be purified from the plant biomass but chromatography steps are hindered by the high concentrations of host cell proteins (HCPs) in plant extracts. However, most HCPs irreversibly aggregate at temperatures above 60 &#176;C facilitating subsequent purification of the target protein. Here, three methods are presented to achieve the heat precipitation of tobacco HCPs in either intact leaves or extracts. The blanching of intact leaves can easily be incorporated into existing processes but may have a negative impact on subsequent filtration steps. The opposite is true for heat precipitation of leaf extracts in a stirred vessel, which can improve the performance of downstream operations albeit with major changes in process equipment design, such as homogenizer geometry. Finally, a heat exchanger setup is well characterized in terms of heat transfer conditions and easy to scale, but cleaning can be difficult and there may be a negative impact on filter capacity. The design-of-experiments approach can be used to identify the most relevant process parameters affecting HCP removal and product recovery. This facilitates the application of each method in other expression platforms and the identification of the most suitable method for a given purification strategy.

Three heat precipitation methods are presented that effectively remove more than 90% of host cell proteins (HCPs) from tobacco extracts prior to any other purification step. The plant HCPs irreversibly aggregate at temperatures above 60 &#176;C.

Vergleich von Tabakwirtszellprotein Abbaumethoden von Intact Pflanzen oder Blanchieren durch Wärmebehandlung von Extrakten

Plants not only provide food, feed and raw materials for humans, but have also been developed as an economical production system for biopharmaceutical ...