Name: customization of aspergillus niger morphology through addition of talc micro particles
Uploaded: 2012-03-15T13:00:00
Duration: 10 min 51 s
Description: Watch this Scientific Journal Video about Customization of Aspergillus niger Morphology Through Addition of Talc Micro Particles at JoVE.com

लेखकों कृतज्ञता सहयोगात्मक अनुसंधान केंद्र 578 SFB Technische Universität ब्राउनश्विक, जर्मनी में जीन से उत्पाद &quot;के माध्यम से जर्मन रिसर्च फाउंडेशन (DFG) द्वारा वित्तीय सहायता प्रदान स्वीकार करते हैं.

<ol>
	<li>Wucherpfennig, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Advances in Applied Microbiology. 72, 89-136 (2010).</li><li>Driouch, H., H&#228;nsch, R., Wucherpfennig, T., Krull, R., Wittmann, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Improved+enzyme+production+by+bio-pellets+of+Aspergillus+niger:+Targeted+morphology+engineering+using+titanate+microparticles.">Improved enzyme production by bio-pellets of Aspergillus niger: Targeted morphology engineering using titanate microparticles.</a> Biotechnology and Bioengineering. 109, 462-471 (2012).</li><li>Driouch, H., Roth, A., Dersch, P., Wittmann, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optimized+bioprocess+for+production+of+fructofuranosidase+by+recombinant+Aspergillus+niger.">Optimized bioprocess for production of fructofuranosidase by recombinant Aspergillus niger.</a> Applied Microbiology and Biotechnology. 87, 2011-2024 (2010).</li><li>Driouch, H., Roth, A., Dersch, P., Wittmann, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Filamentous+fungi+in+good+shape:+Microparticles+for+tailor-made+fungal+morphology+and+enhanced+enzyme+production.">Filamentous fungi in good shape: Microparticles for tailor-made fungal morphology and enhanced enzyme production.</a> Bioengineered Bugs. 2, 100-104 (2011).</li><li>Driouch, H., Sommer, B., Wittmann, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Morphology+engineering+of+Aspergillus+niger+for+improved+enzyme+production.">Morphology engineering of Aspergillus niger for improved enzyme production.</a> Biotechnology and Bioengineering. 105, 1058-1068 (2010).</li><li>Kaup, B. -. A., Ehrich, K., Pescheck, M., Schrader, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microparticle-enhanced+cultivation+of+filamentous+microorganisms:+Increased+chloroperoxidase+formation+by+Caldariomyces+fumago+as+an+example.">Microparticle-enhanced cultivation of filamentous microorganisms: Increased chloroperoxidase formation by Caldariomyces fumago as an example.</a> Biotechnology and Bioengineering. 99, 491-498 (2008).</li><li>Hirayama, M., Sumi, N., Hidaka, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Purification+and+characterization+of+a+fructooligosaccharide-producing+beta-fructofuranosidase+from+Aspergillus+niger+ATCC+20611.">Purification and characterization of a fructooligosaccharide-producing beta-fructofuranosidase from Aspergillus niger ATCC 20611.</a> Agricultural and Biological Chemistry. 53, 667-673 (2006).</li><li>Rajoka, M. I., Yasmeen, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Improved+productivity+of+beta-fructofuranosidase+by+a+derepressed+mutant+of+Aspergillus+niger+form+conventional+and+non-conventional+substrates.">Improved productivity of beta-fructofuranosidase by a derepressed mutant of Aspergillus niger form conventional and non-conventional substrates.</a> World Journal of Microbiology and Biotechnology. 21, 471-478 (2005).</li><li>Zuccaro, A., G&#195;&#182;tze, S., Kneip, S., Dersch, P., Seibel, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tailor-made+fructooligosaccharides+by+a+combination+of+substrate+and+genetic+engineering.">Tailor-made fructooligosaccharides by a combination of substrate and genetic engineering.</a> ChemBioChem. 9, 143-149 (2008).</li><li>Huggett, A. S. G., Nixon, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+glucose+oxidase,+peroxidase,+and+o-dianisidin+in+determination+of+blood+and+urinary+glucose.">Use of glucose oxidase, peroxidase, and o-dianisidin in determination of blood and urinary glucose.</a> The Lancet. , 270-368 (1957).</li><li>Wucherpfenning, T., Hestler, T., Krull, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Morphology+engineering+-+Osmolality+and+its+effect+on+Aspergillus+niger+morphology+and+productivity.">Morphology engineering - Osmolality and its effect on Aspergillus niger morphology and productivity.</a> Microb. Cell Fact. 10, (2011).</li><li>Rasband, W. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> ImageJ. , (1997).</li><li>Papagianni, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantification+of+the+fractal+nature+of+mycelial+aggregation+in+Aspergillus+niger+submerged+cultures.">Quantification of the fractal nature of mycelial aggregation in Aspergillus niger submerged cultures.</a> Microbial Cell Factories. 5, 5 (2006).</li></ol>

मैं खुलासा नहीं है.

कवक आकारिकी की संशोधन जैव प्रौद्योगिकी में रुचि के कई दशकों के बाद से किया गया है. विभिन्न अध्ययनों के पीएच मान, शक्ति इनपुट, तापमान, मध्यम पोषक तत्वों या inoculum 1 एकाग्रता के रूप में चयनित प्रक्रिया पैरामीटर भिन्न करने की कोशिश की है, लेकिन आकारिकी की बल्कि imprecise और अधूरा नियंत्रण, उच्च ऊर्जा लागत, निषेध प्रभाव या उत्पाद अस्थिरता इसके विपरीत, से ग्रस्त हैं, सूक्ष्म कणों की पूरकता tuned ठीक कण आकार और एकाग्रता की भिन्नता के माध्यम से कवक आकारिकी की एक सटीक इंजीनियरिंग की अनुमति देता है. यह नई संभावनाओं के अनुकूलन के लिए और उच्च उत्पादन आकारिकी की दर्जी डिजाइन के लिए ए के साथ जैव प्रौद्योगिकी उत्पादन में सूक्ष्म कणों का उपयोग करने के लिए खोलता है नाइजर और अन्य filamentous सूक्ष्मजीवों. डिजिटल छवि विश्लेषण के लिए एक आसान प्रतिलिपि प्रस्तुत करने योग्य के कवक मैक्रो morphology विशेषताएँ विधि है. हालांकि, आकार, आकार और सतह के चरित्र के लिए मानकों की विविधताआतंकवाद रूपात्मक संरचनाओं के साहित्य में वर्णित कवक जटिल आकृति विज्ञान के त्वरित आकलन करता है. प्रासंगिक मानकों के संयोजन के रूप में प्रस्तुत आकृति विज्ञान संख्या, इस कमी से बचा जाता है और रूपात्मक संरचनाओं के व्यापक लक्षण वर्णन के लिए ही नहीं बल्कि उत्पादकता के साथ सीधे गणितीय संबंध के लिए इस्तेमाल किया जा सकता है. यह फिर से दिया आकारिकी और आकारिकी की प्रक्रिया के लिए इसलिए एक अनुकूलन द्वारा उत्पादकता के एक अनुमान प्रदान संभव की जरूरत है. आकृति विज्ञान नंबर का उपयोग करना, यह संभव है विभिन्न गोली और पेड़ों का झुरमुट 4,5 morphologies के बीच अंतर है. आकृति विज्ञान संख्या के आगे विकास के लिए भग्न आयाम पर विचार करने के लिए वादा किया जा रहा है. एक भग्न आयाम जटिलता और बड़े पैमाने पर एक 13 वस्तु के गुण भरने की एक माप देता है और इसलिए फुई वाला आकारिकी की समग्र लक्षण वर्णन के लिए predestinated है. करोड़एक उच्च उत्पादन फुई वाला morphology eation, तथापि, विशेष रूप से बड़े पैमाने पर खेती में प्रक्रिया प्रदर्शन के साथ समस्याओं का नेतृत्व, क्योंकि फुई वाला विकास के फार्म पहले किया गया है बहुत अधिक से अधिक संस्कृति शोरबा विस्कोसिटी 2 एक्ज़िबिट दिखाया हो सकता है. यह गर्मी और बड़े पैमाने पर स्थानांतरण और स्थिर गैर मिश्रित क्षेत्र है, जो एक उच्च शक्ति इनपुट और खेती और अधिक महंगा करने के लिए 1 संचालित की आवश्यकता के गठन के साथ समस्याओं की ओर जाता है. इसलिए कवक आकारिकी और संस्कृति शोरबा दलदलापन के बीच संबंधों को जब आकारिकी बदल रहा है और आगे के मॉडल में शामिल माना जाना चाहिए.

Table of Equipment:
<table border="1">
	<tbody>
		<tr>
			<td>
			Equipment</td>
			<td>
			Company</td>
			<td>
			Catalogue Number/model</td>
		</tr>
		<tr>
			<td>
			autoclave</td>
			<td>
			Systec</td>
			<td>
			V150</td>
		</tr>
		<tr>
			<td>
			B&uuml;chner funnel (plastic)</td>
			<td>
			VWR</td>
			<td>
			-</td>
		</tr>
		<tr>
			<td>
			cellulose filter (for biomass dry weight)</td>
			<td>
			Sartorius Stedim Biotech</td>
			<td>
			Filter Discs Grade 389</td>
		</tr>
		<tr>
			<td>
			cellulose acetate filter (for air filtration at reactor)</td>
			<td>
			Sartorius stedim biotech</td>
			<td>
			Midisart 200 PTFE</td>
		</tr>
		<tr>
			<td>
			cellulose acetate filter (for enzyme activity)</td>
			<td>
			Sartorius Stedim Biotech</td>
			<td>
			Midisart NML</td>
		</tr>
		<tr>
			<td>
			centrifuge</td>
			<td>
			Eppendorf</td>
			<td>
			Centrifuge 5415R</td>
		</tr>
		<tr>
			<td>
			centrifuge</td>
			<td>
			Heraeus</td>
			<td>
			Biofuge fresco</td>
		</tr>
		<tr>
			<td>
			centrifuge</td>
			<td>
			Heraeus sepatech</td>
			<td>
			Varifuge 3.0R</td>
		</tr>
		<tr>
			<td>
			compartment dryer (105 &deg;C)</td>
			<td>
			Heraeus</td>
			<td>
			Kelvitran t</td>
		</tr>
		<tr>
			<td>
			control unit (temperature)</td>
			<td>
			Jumo</td>
			<td>
			Jumo iTron 08</td>
		</tr>
		<tr>
			<td>
			control unit (pH-value)</td>
			<td>
			meredos</td>
			<td>
			pH Control 2</td>
		</tr>
		<tr>
			<td>
			desiccator</td>
			<td>
			Duran</td>
			<td>
			Vacuum stable</td>
		</tr>
		<tr>
			<td>
			Falcon tubes</td>
			<td>
			Omnilab</td>
			<td>
			FALC352070</td>
		</tr>
		<tr>
			<td>
			heating block 40 &deg;C</td>
			<td>
			Biometra</td>
			<td>
			TB1 Thermoblock</td>
		</tr>
		<tr>
			<td>
			heating block 95 &deg;C</td>
			<td>
			HLC</td>
			<td>
			HBT 130</td>
		</tr>
		<tr>
			<td>
			micro plate reader</td>
			<td>
			Tecan</td>
			<td>
			Sunrise-Microplate-Reader</td>
		</tr>
		<tr>
			<td>
			micro scales</td>
			<td>
			Sartorius</td>
			<td>
			CP 225</td>
		</tr>
		<tr>
			<td>
			microscope (digital inverted)</td>
			<td>
			AMG</td>
			<td>
			EVOS xl</td>
		</tr>
		<tr>
			<td>
			micro pipettes and tips (different sizes)</td>
			<td>
			Omnilab</td>
			<td>
			5283303
			5283298 
			5283299 
			5283300</td>
		</tr>
		<tr>
			<td>
			micro titer plate</td>
			<td>
			Nunc</td>
			<td>
			MaxiSorp</td>
		</tr>
		<tr>
			<td>
			multi pipette and tips</td>
			<td>
			Eppendorf/ Omnilab</td>
			<td>
			5283611/ 5283611</td>
		</tr>
		<tr>
			<td>
			pH-electrode</td>
			<td>
			Schott</td>
			<td>
			pH-Meter CG840</td>
		</tr>
		<tr>
			<td>
			reaction tubes</td>
			<td>
			Roth</td>
			<td>
			E518.1</td>
		</tr>
		<tr>
			<td>
			scale</td>
			<td>
			Sartorius</td>
			<td>
			CP 3202 S</td>
		</tr>
		<tr>
			<td>
			stirred tank bioreactor with equipment</td>
			<td>
			Applikon Biotechnology</td>
			<td>
			2L Bioreactor set</td>
		</tr>
		<tr>
			<td>
			syringe</td>
			<td>
			Eppendorf</td>
			<td>
			Combitips Plus 5 mL</td>
		</tr>
	</tbody>
</table>
Table of Reagents:
<table border="1">
	<tbody>
		<tr>
			<td>
			Name of the reagent</td>
			<td>
			Company </td>
		</tr>
		<tr>
			<td>
			Acetic acid</td>
			<td>
			Roth</td>
		</tr>
		<tr>
			<td>
			Disodium hydrogen phosphate</td>
			<td>
			Merck</td>
		</tr>
		<tr>
			<td>
			Ethanol (95%)</td>
			<td>
			Roth</td>
		</tr>
		<tr>
			<td>
			Glucose monohydrate, (&alpha;-D-)</td>
			<td>
			Roth</td>
		</tr>
		<tr>
			<td>
			Glucose oxidase (Typ II from Aspergillus niger)</td>
			<td>
			Sigma</td>
		</tr>
		<tr>
			<td>
			Hydrochloride acid (37 % w/v)</td>
			<td>
			Fiedel-de Ha&euml;n</td>
		</tr>
		<tr>
			<td>
			Hydrous magnesium silicate</td>
			<td>
			Roth</td>
		</tr>
		<tr>
			<td>
			Monopotassium phosphate</td>
			<td>
			Merck</td>
		</tr>
		<tr>
			<td>
			o-dianoisidine dihydrochloride</td>
			<td>
			Sigma</td>
		</tr>
		<tr>
			<td>
			Peroxidase (Typ II from horseradish)</td>
			<td>
			Sigma</td>
		</tr>
		<tr>
			<td>
			Sodium acetate</td>
			<td>
			Roth</td>
		</tr>
		<tr>
			<td>
			Sodium hydroxide</td>
			<td>
			Merck</td>
		</tr>
		<tr>
			<td>
			Sucrose, D-(+)</td>
			<td>
			Fluka</td>
		</tr>
		<tr>
			<td>
			Water (deionized)</td>
			<td>
			-</td>
		</tr>
	</tbody>
</table>
Table of Solutions and Medium Composition:
<table border="1">
	<tbody>
		<tr>
			<td>
			Solution</td>
			<td>
			Components</td>
			<td>
			Amount</td>
		</tr>
		<tr>
			<td>
			50 mM sodium acetate buffer (pH 6.5)</td>
			<td>
			Sodium acetate
			Bring to volume with deionized water
			Adjust at pH 6.5 with acetic acid</td>
			<td>
			4.1 g L-1</td>
		</tr>
		<tr>
			<td>
			0.05 M monopotassium phosphate solution</td>
			<td>
			Monopotassium phosphate
			Bring to volume with deionized water</td>
			<td>
			6.805 g L-1</td>
		</tr>
		<tr>
			<td>
			0.05 M disodium hydrogen phosphate solution</td>
			<td>
			Disodium hydrogen phosphate
			Bring to volume with deionized water</td>
			<td>
			7.1 g L-1</td>
		</tr>
		<tr>
			<td>
			0.05 M phosphate buffer (pH 7.0)</td>
			<td>
			0.05 M disodium hydrogen phosphate solution
			Bring to volume with 0.05 M monopotassium phosphate solution</td>
			<td>
			61.2 mL</td>
		</tr>
		<tr>
			<td>
			0.05 M phosphate buffer (pH 5.4)</td>
			<td>
			0.05M disodium hydrogen phosphate solution
			Bring to volume with 0.05 M monopotassium phosphate solution</td>
			<td>
			3 mL</td>
		</tr>
		<tr>
			<td>
			1.65 M sucrose solution</td>
			<td>
			D-(+)-sucrose
			Bring to volume with phosphate buffer (pH 5.4)</td>
			<td>
			564.8 g L-1</td>
		</tr>
		<tr>
			<td>
			reagent solution</td>
			<td>
			o-Dianisidin-Dihydrochlorid
			Ethanol (95%)</td>
			<td>
			25 mg
			10 mL</td>
		</tr>
		<tr>
			<td>
			Glucose reagent solution</td>
			<td>
			Glucose oxidase
			Peroxidase
			Phosphate buffer (pH 7.0)
			reagent solution</td>
			<td>
			10.5 mg
			3 mg
			90 mL
			10 mL</td>
		</tr>
	</tbody>
</table>

customization of aspergillus niger morphology through addition of talc micro particles

The filamentous fungus A. niger is a widely used strain in a broad range of industrial processes from food to pharmaceutical industry. One of the most intriguing and often uncontrollable characteristics of this filamentous organism is its complex morphology. It ranges from dense spherical pellets to viscous mycelia (Figure 1). Various process parameters and ingredients are known to influence fungal morphology 1. Since optimal productivity correlates strongly with a specific morphological form, the fungal morphology often represents the bottleneck of productivity in industrial production.
A straight forward and elegant approach to precisely control morphological shape is the addition of inorganic insoluble micro particles (like hydrous magnesium silicate, aluminum oxide or titanium silicate oxide) to the culture medium contributing to increased enzyme production 2-6. Since there is an obvious correlation between micro particle dependent morphology and enzyme production it is desirable to mathematically link productivity and morphological appearance. Therefore a quantitative precise and holistic morphological description is targeted.
Thus, we present a method to generate and characterize micro particle dependent morphological structures and to correlate fungal morphology with productivity (Figure 1) which possibly contributes to a better understanding of the morphogenesis of filamentous microorganisms.
The recombinant strain A. niger SKAn1015 is cultivated for 72 h in a 3 L stirred tank bioreactor. By addition of talc micro particles in concentrations of 1 g/L, 3 g/L and 10 g/L prior to inoculation a variety of morphological structures is reproducibly generated. Sterile samples are taken after 24, 48 and 72 hours for determination of growth progress and activity of the produced enzyme. The formed product is the high-value enzyme &beta;-fructofuranosidase, an important biocatalyst for neo-sugar formation in food or pharmaceutical industry, which catalyzes among others the reaction of sucrose to glucose 7-9. Therefore, the quantification of glucose after adding sucrose implies the amount of produced &beta;-fructofuranosidase. Glucose quantification is made by a GOD/POD-Assay 10, which is modified for high-throughput analysis in 96-well micro titer plates.
Fungal morphology after 72 hours is examined by microscope and characterized by digital image analysis. In doing so, particle shape factors for fungal macro morphology like Feret's diameter, projected area, perimeter, circularity, aspect ratio, roundness und solidity are calculated with the open source image processing program ImageJ. Relevant parameters are combined to a dimensionless Morphology number (Mn) 11, which enables a comprehensive characterization of fungal morphology. The close correlation of the Morphology number and productivity are highlighted by mathematical regression.

Watch this Scientific Journal Video about Customization of Aspergillus niger Morphology Through Addition of Talc Micro Particles at JoVE.com

Customization of Aspergillus niger Morphology Through Addition of Talc Micro Particles

एक ठीक करने के लिए पैदा करते हैं और विधि के लिए व्यापक filamentous कवक की आकारिकी विशेषताएँ<em&gt; Aspergillus नाइजर</em&gt; वर्णित है, जो रूपात्मक उपस्थिति और उत्पादकता के गणितीय संबंध की अनुमति देता है.

के अनुकूलन Aspergillus नाइजर</emपाउडर सूक्ष्म कणों के माध्यम से इसके अलावा आकृति विज्ञान>

The filamentous fungus A. niger is a widely used strain in a broad range of industrial processes from food to pharmaceutical industry. One of the most ...

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Immunology and Infection

Customization of Aspergillus niger Morphology Through Addition of Talc Micro Particles

Packaging HIV- or FIV-based Lentivector Expression Constructs &amp; Transduction of VSV-G Pseudotyped Viral Particles

As with standard plasmid vectors, it is possible to transfect lentivectors in plasmid form into cells with low-to-medium efficiency to obtain transient expression of effectors. Packaging lentiviral expression constructs into pseudoviral particles, however, enables up to 100% transduction, even with difficult-to-transfect cells, such as primary, stem, and differentiated cells. Moreover, the lentiviral delivery does not produce the specific cellular responses typically associated with chemical transfections, such as cell death resulting from toxicity of the transfection reagent 1, 2. When transduced into target cells, the lentiviral construct integrates into genomic DNA and provides stable expression of the small hairpin RNA (shRNA), cDNA, microRNA or reporter gene 3, 4. Target cells stably expressing the effector molecule can be isolated using a selectable marker contained in the expression vector construct such as puromycin or GFP. After pseudoviral particles infect target cells, they cannot replicate within target cells because the viral structural genes are absent and the long terminal repeats (LTRs) are designed to be self-inactivating upon transduction 5, 6.
There are three main components necessary for efficient lentiviral packaging 1, 5, 6, 7. 
1. The lentiviral expression vector that contains some of the genetic elements required for packaging, stable integration of the viral expression construct into genomic DNA, and expression of the effector or reporter. 
2. The lentiviral packaging plasmids that provide the proteins essential for transcription and packaging of an RNA copy of the expression construct into recombinant pseudoviral particles. This protocol uses the pPACK plasmids (SBI) that encode for gag, pol, and rev from the HIV or FIV genome and Vesicular Stomatitis Virus g protein (VSV-G) for the viral coat protein. 
3. 293TN producer cells (derived from HEK293 cells) that express the SV40 large T antigen, which is required for high-titer lentiviral production and a neomycin resistance gene, useful for reselecting the cells for maintenance.
An overview of the viral production protocol can be seen in Figure 1. Viral production starts by co-transfecting 293TN producer cells with the lentiviral expression vector and the packaging plasmids. Viral particles are secreted into the media. After 48-72 hours the cell culture media is harvested. Cellular debris is removed from the cell culture media, and the viral particles are precipitated by centrifugation with PEG-it for concentration. Produced lentiviral particles are then titered and can be used to transduce target cells. Details of viral titering are not included in this protocol, but can be found at:
<a href="http://www.systembio.com/downloads/global_titer_kit_web_090710.pdf" target="_blank">http://www.systembio.com/downloads/global_titer_kit_web_090710.pdf</a> 8.
This protocol has been optimized using the specific products indicated. Other reagents may be substituted, but the same results cannot be guaranteed.

Packaging HIV- or FIV-based Lentivector Expression Constructs & Transduction of VSV-G Pseudotyped Viral Particles

Lentiviral expression vectors are the most effective vehicles for stably expressing different effector molecules or reporter constructs in dividing and non-dividing mammalian cells and whole organisms. Here we provide a protocol on how to package lentivector expression constructs in pseudoviral particles and to transduce target cells using the pseudoviral particles.

पैकेजिंग एचआईवी या FIV आधारित Lentivector अभिव्यक्ति constructs और VSV जी Pseudotyped वायरल कणों की transduction

As with standard plasmid vectors, it is possible to transfect lentivectors in plasmid form into cells with low-to-medium efficiency to obtain transient ...

Detection of Fluorescent Nanoparticle Interactions with Primary Immune Cell Subpopulations by Flow Cytometry

Engineered nanoparticles are endowed with very promising properties for therapeutic and diagnostic purposes. This work describes a fast and reliable method of analysis by flow cytometry to study nanoparticle interaction with immune cells. Primary immune cells can be easily purified from human or mouse tissues by antibody-mediated magnetic isolation. In the first instance, the different cell populations running in a flow cytometer can be distinguished by the forward-scattered light (FSC), which is proportional to cell size, and the side-scattered light (SSC), related to cell internal complexity. Furthermore, fluorescently labeled antibodies against specific cell surface receptors permit the identification of several subpopulations within the same sample. Often, all these features vary when cells are boosted by external stimuli that change their physiological and morphological state. Here, 50 nm FITC-SiO2 nanoparticles are used as a model to identify the internalization of nanostructured materials in human blood immune cells. The cell fluorescence and side-scattered light increase after incubation with nanoparticles allowed us to define time and concentration dependence of nanoparticle-cell interaction. Moreover, such protocol can be extended to investigate Rhodamine-SiO2 nanoparticle interaction with primary microglia, the central nervous system resident immune cells, isolated from mutant mice that specifically express the Green Fluorescent Protein (GFP) in the monocyte/macrophage lineage. Finally, flow cytometry data related to nanoparticle internalization into the cells have been confirmed by confocal microscopy.

Analysis of nanoparticle interaction with defined subpopulations of immune cells by flow cytometry.

फ्लो द्वारा प्राथमिक प्रतिरक्षा सेल subpopulations साथ फ्लोरोसेंट Nanoparticle बातचीत का पता लगाने

Engineered nanoparticles are endowed with very promising properties for therapeutic and diagnostic purposes. This work describes a fast and reliable ...

Modeling The Lifecycle Of Ebola Virus Under Biosafety Level 2 Conditions With Virus-like Particles Containing Tetracistronic Minigenomes

Ebola viruses cause severe hemorrhagic fevers in humans and non-human primates, with case fatality rates as high as 90%. There are no approved vaccines or specific treatments for the disease caused by these viruses, and work with infectious Ebola viruses is restricted to biosafety level 4 laboratories, significantly limiting the research on these viruses. Lifecycle modeling systems model the virus lifecycle under biosafety level 2 conditions; however, until recently such systems have been limited to either individual aspects of the virus lifecycle, or a single infectious cycle. Tetracistronic minigenomes, which consist of Ebola virus non-coding regions, a reporter gene, and three Ebola virus genes involved in morphogenesis, budding, and entry (VP40, GP1,2, and VP24), can be used to produce replication and transcription-competent virus-like particles (trVLPs) containing these minigenomes. These trVLPs can continuously infect cells expressing the Ebola virus proteins responsible for genome replication and transcription, allowing us to safely model multiple infectious cycles under biosafety level 2 conditions. Importantly, the viral components of this systems are solely derived from Ebola virus and not from other viruses (as is, for example, the case in systems using pseudotyped viruses), and VP40, GP1,2 and VP24 are not overexpressed in this system, making it ideally suited for studying morphogenesis, budding and entry, although other aspects of the virus lifecycle such as genome replication and transcription can also be modeled with this system. Therefore, the tetracistronic trVLP assay represents the most comprehensive lifecycle modeling system available for Ebola viruses, and has tremendous potential for use in investigating the biology of Ebola viruses in future. Here, we provide detailed information on the use of this system, as well as on expected results.

Work with infectious Ebola viruses is restricted to biosafety level 4 laboratories. Tetracistronic minigenome-containing replication and transcription-competent virus like particles (trVLPs) represent a lifecycle modeling system that allows us to safely model multiple infectious cycles under biosafety level 2 conditions, relying exclusively on Ebola virus components.

Tetracistronic Minigenomes युक्त वायरस की तरह कणों के साथ जैव सुरक्षा स्तर 2 शर्तों के तहत Ebola वायरस के जीवन चक्र मॉडलिंग

Ebola viruses cause severe hemorrhagic fevers in humans and non-human primates, with case fatality rates as high as 90%. There are no approved vaccines or ...

Optimization of a Quantitative Micro-neutralization Assay

The micro-neutralization (MN) assay is a standard technique for measuring the infectivity of the influenza virus and the inhibition of virus replication. In this study, we present the protocol of an imaging-based MN assay to quantify the true antigenic relationships between viruses. Unlike typical plaque reduction assays that rely on visible plaques, this assay quantitates the entire infected cell population of each well. The protocol matches the virus type or subtype with the selection of cell lines to achieve maximum infectivity, which enhances sample contrast during imaging and image processing. The introduction of quantitative titration defines the amount of input viruses of neutralization and enables the results from different experiments to be comparable. The imaging setup with a flatbed scanner and free downloadable software makes the approach high throughput, cost effective, user friendly, and easy to deploy in most laboratories. Our study demonstrates that the improved MN assay works well with the current circulating influenza A(H1N1)pdm09, A(H3N2), and B viruses, without being significantly influenced by amino acid substitutions in the neuraminidase (NA) of A(H3N2) viruses. It is particularly useful for the characterization of viruses that either grow to low HA titer and/or undergo an abortive infection resulting in an inability to form plaques in cultured cells.

This study describes an imaging-based micro-neutralization assay to analyze the antigenic relationships between viruses. The protocol employs a flatbed scanner and has four steps, including titration, titration quantitation, neutralization, and neutralization quantitation. The assay works well with current circulating influenza A(H1N1)pdm09, A(H3N2), and B viruses.

एक मात्रात्मक माइक्रो निराकरण परख के अनुकूलन

The micro-neutralization (MN) assay is a standard technique for measuring the infectivity of the influenza virus and the inhibition of virus replication. ...

Production of Pseudotyped Particles to Study Highly Pathogenic Coronaviruses in a Biosafety Level 2 Setting

The protocol aims to generate coronavirus (CoV) spike (S) fusion protein pseudotyped particles with a murine leukemia virus (MLV) core and luciferase reporter, using a simple transfection procedure of the widely available HEK-293T cell line. Once formed and released from producer cells, these pseudovirions incorporate a luciferase reporter gene. Since they only contain the heterologous coronavirus spike protein on their surface, the particles behave like their native coronavirus counterparts for entry steps. As such, they are the excellent surrogates of native virions for studying viral entry into host cells. Upon successful entry and infection into target cells, the luciferase reporter gets integrated into the host cell genome and is expressed. Using a simple luciferase assay, transduced cells can be easily quantified. An important advantage of the procedure is that it can be performed in biosafety level 2 (BSL-2) facilities instead of BSL-3 facilities required for work with highly pathogenic coronaviruses such as Middle East respiratory syndrome coronavirus (MERS-CoV) and severe acute respiratory syndrome coronavirus (SARS-CoV). Another benefit comes from its versatility as it can be applied to envelope proteins belonging to all three classes of viral fusion proteins, such as the class I influenza hemagglutinin (HA) and Ebola virus glycoprotein (GP), the class II Semliki forest virus E1 protein, or the class III vesicular stomatitis virus G glycoprotein. A limitation of the methodology is that it can only recapitulate virus entry steps mediated by the envelope protein being investigated. For studying other viral life cycle steps, other methods are required. Examples of the many applications these pseudotype particles can be used in include investigation of host cell susceptibility and tropism and testing the effects of virus entry inhibitors to dissect viral entry pathways used.

Here, we present a protocol to generate pseudotyped particles in a BSL-2 setting incorporating the spike protein of the highly pathogenic viruses Middle East respiratory syndrome and severe acute respiratory syndrome coronaviruses. These pseudotyped particles contain a luciferase reporter gene allowing quantification of virus entry into target host cells.

जैव सुरक्षा स्तर 2 की स्थापना में अत्यधिक रोगजनक कोरोनावायरस का अध्ययन करने के लिए स्यूडोटाइप कणों का उत्पादन

The protocol aims to generate coronavirus (CoV) spike (S) fusion protein pseudotyped particles with a murine leukemia virus (MLV) core and luciferase ...

Measuring Phagocytosis of Aspergillus fumigatus Conidia by Human Leukocytes using Flow Cytometry

Invasive pulmonary infection by the mold Aspergillus fumigatus poses a great threat to immunocompromised patients. Inhaled fungal conidia (spores) are cleared from the human lung alveoli by being phagocytosed by innate monocytes and/or neutrophils. This protocol offers a fast and reliable measurement of phagocytosis by flow cytometry using fluorescein isothiocyanate (FITC)-labeled conidia for co-incubation with human leukocytes and subsequent counterstaining with an anti-FITC antibody to allow discrimination of internalized and cell-adherent conidia. Major advantages of this protocol are its rapidness, the possibility to combine the assay with cytometric analysis of other cell markers of interest, the simultaneous analysis of monocytes and neutrophils from a single sample and its applicability to other cell wall-bearing fungi or bacteria. Determination of percentages of phagocytosing leukocytes provides a means to microbiologists for evaluating virulence of a pathogen or for comparing pathogen wildtypes and mutants as well as to immunologists for investigating human leukocyte capabilities to combat pathogens.

Measuring Phagocytosis of Aspergillus fumigatus Conidia by Human Leukocytes using Flow Cytometry

This protocol provides a fast and reliable method to quantitatively measure phagocytosis of Aspergillus fumigatus conidia by human primary phagocytes using flow cytometry and to discriminate phagocytosis of conidia from mere adhesion to leukocytes.

फ्लो साइटोमेट्री का उपयोग करके मानव ल्यूकोसाइट्स द्वारा एस्परगिलस फ्यूमिगटस कोनिडिया के फागोसाइटोसिस को मापना

Invasive pulmonary infection by the mold Aspergillus fumigatus poses a great threat to immunocompromised patients. Inhaled fungal conidia (spores) are ...

Production of High-Titer Infectious Influenza Pseudotyped Particles with Envelope Glycoproteins from Highly Pathogenic H5N1 and Avian H7N9 Viruses

The occasional direct transmission of the highly pathogenic avian influenza A virus H5N1 (HPAI H5N1) and H7N9 to humans and their lethality are serious public health issues and suggest the possibility of an epidemic. However, our molecular understanding of the virus is rudimentary, and it is necessary to study the biological properties of its envelope proteins as therapeutic targets and to develop strategies to control infection. We developed a solid viral pseudotyped particle (pp) platform to study avian influenza virus, including the functional analysis of its hemagglutinin (HA) and neuraminidase (NA) envelope glycoproteins, the reassortment characteristics of the HAs and NAs, receptors, tropisms, neutralizing antibodies, diagnosis, infectivity, for the purposes of drug development and vaccine design. Here, we describe an experimental procedure to establish pps with the envelope glycoproteins (HA, NA) from two influenza A strains (HAPI H5N1 and 2013 avian H7N9). Their generation is based on the capacity of some viruses, such as murine leukemia virus (MLV), to incorporate envelope glycoproteins into a pp. In addition, we also detail how these pps are quantified with RT-qPCR, and the infectivity detection of native and mismatched virus pps depending on the origin of the HAs and NAs. This system is highly flexible and adaptable and can be used to establish viral pps with envelope glycoproteins that can be incorporated in any other type of enveloped virus. Thus, this viral particle platform can be used to study wild viruses in many research investigations.

This protocol describes an experimental process to produce high-titer infectious viral pseudotyped particles (pp) with envelope glycoproteins from two influenza A strains and how to determine their infectivity. This protocol is highly adaptable to develop pps of any other type of enveloped viruses with different envelope glycoproteins.

अत्यधिक रोगजनक एच5एन1 और एवियन एच7एन9 वायरस से लिफाफा ग्लाइकोप्रोटीन के साथ उच्च टिटर संक्रामक इन्फ्लूएंजा स्यूडोटाइप कणों का उत्पादन

The occasional direct transmission of the highly pathogenic avian influenza A virus H5N1 (HPAI H5N1) and H7N9 to humans and their lethality are serious ...

Quantifying Human Norovirus Virus-like Particles Binding to Commensal Bacteria Using Flow Cytometry

Commensal bacteria are well established to impact infection of eukaryotic viruses. Direct binding between the pathogen and the host microbiome is responsible for altering infection for many of these viruses. Thus, characterizing the nature of virus-bacteria binding is a foundational step needed for elucidating the mechanism(s) by which bacteria alter viral infection. For human norovirus, commensal bacteria enhance B cell infection. The virus directly binds to these bacteria, indicating that this direct interaction is involved in the mechanism of infection enhancement. A variety of techniques can be used to quantify interactions between bacteria and viruses including scintillation counting of radiolabeled viruses and polymerase chain reaction (PCR). Both methods require the use of live virus, which may need to be generated in the laboratory. Currently, none of the established in vitro culture systems available for human norovirus are robust enough to allow for generation of highly concentrated viral stocks. In lieu of live virus, virus-like particles (VLPs) have been used to characterize the interactions between norovirus and bacteria. Herein a flow cytometry method is described with uses virus specific antibodies to quantify VLP binding to gram-negative and gram-positive bacteria. Inclusion of both bacteria only and isotype controls allowed for optimization of the assay to reduce background antibody binding and accurate quantification of VLP attachment to the bacteria tested. High VLP:bacterium ratios result in VLPs binding to large percentages of the bacterial population. However, when VLP quantities are decreased, the percent of bacteria bound also decreases. Ultimately, this method can be employed in future experiments elucidating the specific conditions and structural components that regulate norovirus:bacterial interactions.

The goal of this protocol is to quantify binding of the eukaryotic pathogen human norovirus to bacteria. After performing an initial virus-bacterium attachment assay, flow cytometry is used to detect virally-bound bacteria within the population.

फ्लो साइटोमेट्री का उपयोग करके कॉममेंसल बैक्टीरिया के लिए बाध्यकारी मानव नोरोवायरस वायरस जैसे कणों की मात्रा

Commensal bacteria are well established to impact infection of eukaryotic viruses. Direct binding between the pathogen and the host microbiome is ...

Infection of Zebrafish Larvae with Aspergillus Spores for Analysis of Host-Pathogen Interactions

Invasive aspergillosis (IA) is one of&#160;the most common fungal infections among immunocompromised individuals. Despite the availability of antifungal drugs, IA can cause &#62;50% mortality in infected immunocompromised patients. It is crucial to determine both host and pathogen factors that contribute to infection susceptibility and low survival rates in infected patients in order to develop novel therapeutics. Innate immune responses play a pivotal role in recognition and clearance of Aspergillus spores, though little is known about the exact cellular and molecular mechanisms. Reliable models are required to investigate detailed mechanistic interactions between the host and pathogen. The optical clarity and genetic tractability of zebrafish larvae make them an intriguing model&#160;to study host-pathogen interactions of multiple human bacterial and fungal infections in a live and intact host. This protocol describes a larval zebrafish Aspergillus infection model. First, Aspergillus spores are isolated and injected into the zebrafish hindbrain ventricle via microinjection. Then, chemical inhibitors such as immunosuppressive drugs are added directly to the larval water. Two methods to monitor the infection in injected larvae are described, including the 1) homogenization of larvae for colony forming unit (CFU) enumeration and 2) a repeated, daily live imaging setup. Overall, these techniques can be used to mechanistically analyze the progression of Aspergillus infection in vivo and can be applied to different host backgrounds and Aspergillus strains to interrogate host-pathogen interactions.

Infection of Zebrafish Larvae with Aspergillus Spores for Analysis of Host-Pathogen Interactions

This protocol describes an Aspergillus infection model in zebrafish larvae. Aspergillus spores are microinjected into the hindbrain of larvae, and chemical treatment is used to induce immunosuppression. Infection progression is monitored via a daily imaging setup to monitor fungal growth and immune responses as well as enumeration of live spores by colony forming unit plating.

मेजबान-रोगजनक इंटरैक्शन के विश्लेषण के लिए एस्परगिलस बीजाणुओं के साथ जेब्राफिश लार्वा का संक्रमण

Invasive aspergillosis (IA) is one of&#160;the most common fungal infections among immunocompromised individuals. Despite the availability of antifungal ...

Supervised Machine Learning for Semi-Quantification of Extracellular DNA in Glomerulonephritis

Glomerular cell death is a pathological feature of myeloperoxidase anti neutrophil cytoplasmic antibody associated vasculitis (MPO-AAV). Extracellular deoxyribonucleic acid (ecDNA) is released during different forms of cell death including apoptosis, necrosis, necroptosis, neutrophil extracellular traps (NETs) and pyroptosis. Measurement of this cell death is time consuming with several different biomarkers required to identify the different biochemical forms of cell death. Measurement of ecDNA is generally conducted in serum and urine as a surrogate for renal damage, not in the actual target organ where the pathological injury occurs. The current difficulty in investigating ecDNA in the kidney is the lack of methods for formalin fixed paraffin embedded tissue (FFPE) both experimentally and in archived human kidney biopsies. This protocol provides a summary of the steps required to stain for ecDNA in FFPE tissue (both human and murine), quench autofluorescence and measure the ecDNA in the resulting images using a machine learning tool from the publicly available open source ImageJ plugin trainable Weka segmentation. Trainable Weka segmentation is applied to ecDNA within the glomeruli where the program learns to classify ecDNA. This classifier is applied to subsequent acquired kidney images, reducing the need for manual annotations of each individual image. The adaptability of the trainable Weka segmentation is demonstrated further in kidney tissue from experimental murine anti-MPO glomerulonephritis (GN), to identify NETs and ecMPO, common pathological contributors to anti-MPO GN. This method provides objective analysis of ecDNA in kidney tissue that demonstrates clearly the efficacy in which the trainable Weka segmentation program can distinguish ecDNA between healthy normal kidney tissue and diseased kidney tissue. This protocol can easily be adapted to identify ecDNA, NETs and ecMPO in other organs.

Extracellular DNA (ecDNA) released during cell death is proinflammatory and contributes to inflammation. Measurement of ecDNA at the site of injury can determine the efficacy of therapeutic treatment in the target organ. This protocol describes the use of a machine learning tool to automate measurement of ecDNA in kidney tissue.

ग्लोमेरुलोनेफ्राइटिस में एक्स्ट्रासेलुलर डीएनए के अर्ध-क्वांटिफिकेशन के लिए पर्यवेक्षित मशीन लर्निंग

Glomerular cell death is a pathological feature of myeloperoxidase anti neutrophil cytoplasmic antibody associated vasculitis (MPO-AAV). Extracellular ...