The work of our laboratory was funded by a grant from the Consejo Nacional de Ciencia y Tecnolog&#237;a (CONACyT 219893) to SMTHS. This research was also supported by a fellowship granted to RJPK (No. 37938) by CONACyT and the Sistema Nacional de Investigadores (4422). The authors thank CIATEJ for the use of its installations during the writing of this manuscript. Special thanks are extended to Dr. V&#237;ctor Manuel Gonz&#225;lez Mendoza for all recommendations in the molecular biology section&#160;and Valent&#237;n Mendoza Rodr&#237;guez, IFC, UNAM for the facilities during the filming of this article.

1. Caffeine Extraction in Cell Suspensions of C. arabica L.
<ol>
	<li>Use C. arabica cell suspensions9. Maintain the suspensions by biweekly subcultures in Murashige and Skoog medium at pH 4.3 with constant 100 rpm shaking at 25 &#176;C under continuous light (8.3 W/m2).</li>
	<li>Harvest the cells under vacuum filtration using 11 &#181;m pore filter paper and a Buchner funnel.</li>
	<li>Register the fresh weight of the collected cells using a scale, wrap them in alu...

<ol>
	<li>Ferruzzi, M. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+influence+of+beverage+composition+on+delivery+of+phenolic+compounds+from+coffee+and+tea.">The influence of beverage composition on delivery of phenolic compounds from coffee and tea.</a> Physiolgy &amp; Behavior. 100 (1), 33-41 (2010).</li><li>Majheni&#269;, L., &#352;kerget, M., Knez, &. #. 3. 8. 1. ;. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antioxidant+and+antimicrobial+activity+of+guarana+seed+extracts.">Antioxidant and antimicrobial activity of guarana seed extracts.</a> Food Chemistry. 104 (3), 1258-1268 (2007).</li><li>Sledz, W., Los, E., Paczek, A., Rischka, J., Motyka, A., Zoledowska, S., Lojkowska, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antibacterial+activity+of+caffeine+against+plant+pathogenic+bacteria.">Antibacterial activity of caffeine against plant pathogenic bacteria.</a> Acta Biochimica Polonica. 62 (3), 605-612 (2015).</li><li>Lipton, R. B., Diener, H. C., Robbins, M. S., Garas, S. Y., Patel, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Caffeine+in+the+management+of+patients+with+headache.">Caffeine in the management of patients with headache.</a> Journal of Headache and Pain. 18 (1), 1-11 (2017).</li><li>De Mejia, E. G., Ramirez-Mares, M. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Impact+of+caffeine+and+coffee+on+our+health.">Impact of caffeine and coffee on our health.</a> Trends in Endocrinology &amp; Metabolism. 25 (10), 489-492 (2014).</li><li>Uefuji, H., Tatsumi, Y., Morimoto, M., Kaothien-Nakayama, P., Ogita, S., Sano, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Caffeine+production+in+tobacco+plants+by+simultaneous+expression+of+three+coffee+N-methyltrasferases+and+its+potential+as+a+pest+repellant.">Caffeine production in tobacco plants by simultaneous expression of three coffee N-methyltrasferases and its potential as a pest repellant.</a> Plant Molecular Biology. 59 (2), 221-227 (2005).</li><li>Denoeud, F., Carretero-Paulet, L., Dereeper, A., Droc, G., Guyot, R., Pietrella, M., Aury, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+coffee+genome+provides+insight+into+the+convergent+evolution+of+caffeine+biosynthesis.">The coffee genome provides insight into the convergent evolution of caffeine biosynthesis.</a> Science. 345 (6201), 1181-1184 (2014).</li><li>Kurata, H., Matsumura, S., Furusaki, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Light+irradiation+causes+physiological+and+metabolic+changes+for+purine+alkaloid+production+by+a+Coffea+arabica+cell+suspension+culture.">Light irradiation causes physiological and metabolic changes for purine alkaloid production by a Coffea arabica cell suspension culture.</a> Plant Science. 123 (1-2), 197-203 (1997).</li><li>Pech-K&#250;, R., Mu&#241;oz-S&#225;nchez, J. A., Monforte-Gonz&#225;lez, M., V&#225;zquez-Flota, F., Rodas-Junco, B. A., Gonz&#225;lez-Mendoza, V. M., Hern&#225;ndez-Sotomayor, S. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Relationship+between+aluminum+stress+and+caffeine+biosynthesis+in+suspension+cells+of+Coffea+arabica+L.">Relationship between aluminum stress and caffeine biosynthesis in suspension cells of Coffea arabica L.</a> Journal of Inorganic Biochemistry. 181, 177-182 (2018).</li><li>Huang, R., O'Donnell, A. J., Barboline, J. J., Barkman, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Convergent+evolution+of+caffeine+in+plants+by+co-option+of+exapted+ancestral+enzymes.">Convergent evolution of caffeine in plants by co-option of exapted ancestral enzymes.</a> Proceedings of the National Academy of Sciences. 113 (38), 10613-10618 (2016).</li><li>Mizuno, K., Okuda, A., Kato, M., Yoneyama, N., Tanaka, H., Ashihara, H., Fujimura, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+of+a+new+dual-functional+caffeine+synthase+gene+encoding+an+enzyme+for+the+conversion+of+7-methylxanthine+to+caffeine+from+coffee+(Coffea+arabica+L.).">Isolation of a new dual-functional caffeine synthase gene encoding an enzyme for the conversion of 7-methylxanthine to caffeine from coffee (Coffea arabica L.).</a> FEBS letters. 534 (1-3), 75-81 (2003).</li><li>Kato, M., Mizuno, K., Fujimura, T., Iwama, M., Irie, M., Crozier, A., Ashihara, 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+caffeine+synthase+from+tea+leaves.">Purification and characterization of caffeine synthase from tea leaves.</a> Plant Physiology. 120 (2), 579-586 (1999).</li><li>Livak, K. J., Schmittgen, T. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analysis+of+relative+gene+expression+data+using+real-time+quantitative+PCR+and+the+2(-Delta+Delta+C(T))+Method.">Analysis of relative gene expression data using real-time quantitative PCR and the 2(-Delta Delta C(T)) Method.</a> Method. 25 (4), 402-408 (2001).</li><li>Kurata, H., Achioku, T., Furusaki, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+light/dark+cycle+operation+with+an+hour-scale+period+enhances+caffeine+production+by+Coffea+arabica+cells.">The light/dark cycle operation with an hour-scale period enhances caffeine production by Coffea arabica cells.</a> Enzyme and Microbial Technology. 23 (7-8), 518-523 (1998).</li><li>Sartor, R. M., Mazzafera, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Caffeine+formation+by+suspension+cultures+of+Coffea+dewevrei.">Caffeine formation by suspension cultures of Coffea dewevrei.</a> Brazilian Archives of Biology Technology. 43 (1), 1-9 (2000).</li><li>Koshiro, Y., Zheng, X. Q., Wang, M. L., Nagai, C., Ashihara, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Changes+in+content+and+biosynthetic+activity+of+caffeine+and+trigonelline+during+growth+and+ripening+of+Coffea+arabica+and+Coffea+canephora+fruits.">Changes in content and biosynthetic activity of caffeine and trigonelline during growth and ripening of Coffea arabica and Coffea canephora fruits.</a> Plant Science. 171 (2), 242-250 (2006).</li><li>Schimpl, F. C., Kiyota, E., Mayer, J. L. S., de Carvalho Gon&#231;alves, J. F., da Silva, J. F., Mazzafera, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Molecular+and+biochemical+characterization+of+caffeine+synthase+and+purine+alkaloid+concentration+in+guarana+fruit.">Molecular and biochemical characterization of caffeine synthase and purine alkaloid concentration in guarana fruit.</a> Phytochemistry. 105, 25-36 (2014).</li><li>Perrois, C., Strickler, S. R., Mathieu, G., Lepelley, M., Bedon, L., Michaux, S., Privat, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differential+regulation+of+caffeine+metabolism+in+Coffea+arabica+(Arabica)+and+Coffea+canephora+(Robusta).">Differential regulation of caffeine metabolism in Coffea arabica (Arabica) and Coffea canephora (Robusta).</a> Planta. 241 (1), 179-191 (2015).</li></ol>

The authors have nothing to disclose.

We present here the optimal conditions for evaluating the caffeine content, CS activity and transcript levels in an in vitro plant tissue culture, such as cell suspensions of C. arabica. Previous reports have confirmed that maintaining cells under light irradiation and in the presence of theobromine in the culture medium are suitable parameters for increasing the level of caffeine, making it possible to evaluate the caffeine separation methods using reversed-phase high-performance liquid chromatography ...

Caffeine is a secondary metabolite that is biosynthesized by plants of the genus Coffea1. This alkaloid belongs to the methylxanthine family and is regarded as a chemical plant defense because it can act against the adverse effects of pathogens and herbivores2,3. In addition, this metabolite is responsible for the stimulating properties of the coffee drink, which is commonly consumed worldwide4,5. Due to its properties, several research groups are interested in studying the biosynthetic pathway and catabolism of caffeine6,7. Currently, plant in vitro cell/tissue cultures serve as an alternative for evaluating caffeine accumulation under various biotic and abiotic strategies8,9.
Caffeine biosynthesis involves the hydrolytic release of 7-methylxanthine from the corresponding ribose nucleoside followed by ordered N-methylations at positions 3 and 1. A specific S-adenosyl methionine (SAM)-dependent N-methyltransferase (NMT) catalyzes the methylation at position 7, whereas theobromine synthase (TS) and CS are involved in the 3- and 1-methylations, respectively, producing theobromine and caffeine. The study of genes encoding distinct NMTs has allowed understanding the mechanism that regulates caffeine production10,11. CS, which has N-methyltransferase activity, catalyzes the last two steps of the biosynthetic pathway of caffeine11. In coffee tree seedlings, it has been shown that light radiation can increase CS activity, which results in an increase in caffeine biosynthesis. Recently, we showed that the maintenance of cell suspensions of C. arabica L. under light irradiation is the optimal condition for evaluating the effects that produce abiotic stress factors impacting the biosynthetic pathway of caffeine8. The information obtained in these studies may have applications in metabolic engineering and systems biology for maximizing the study of the caffeine biosynthetic pathway in such in vitro systems.
Given the advantages of obtaining a suitable model for the study of caffeine biosynthesis, we optimized the extraction conditions for caffeine on cell suspensions of C. arabica L. It was also possible to develop a useful protocol for studying the enzymatic activity as well as methodological steps for assessing the level of gene transcripts of Coffea caffeine synthase 1 (CCS1) encoding this enzyme. Herein, we report a protocol to extract and quantify caffeine in C. arabica cell suspensions by thin-layer chromatography and densitometry (TLC-densitometry).

<table border="0" cellpadding="0" cellspacing="0" style="width:883px;" width="883">
	<tbody>
		<tr>
			<td>Murashige &#38; Skoog Basal salt mixture</td>
			<td>PhytoTechnology Laboratories</td>
			<td>M524</td>
			<td>Packge Size: 50 L 
			Reagent (mg/L) 
			Ammonium Nitrate (1650) 
			Boric acid (6.2) 
			Calcium chloride, anhydrous (322.2) 
			Cobalt Chloride&#8226;H2O (0.025) 
			Cupric Sulfate&#8226;5H2O (0.025) 
			Na2EDTA&#8226;2H2O (37.26) 
			Ferrous Sulfate&#8226;7H2O (27.8) 
			Magnesium Sulfate, Anhydrous (180.7) 
			Manganese Sulfate&#8226;H2O (16.9) 
			Molybdic Acid (Sodium Salt)&#8226; 2H2O (0.25) 
			Potassium Iodide (0.83) 
			Potassium Nitrate (1900) 
			Potassium Phosphate, Monobasic (170) 
			Zinc Sulfate&#8226;7H2O (8.6) 
			Supplemented with 
			myo-inositol (100) 
			thiamine (10) 
			cysteine (25) 
			sucrose (30000) 
			2,4-dichlorophenoxyacetic acid (3) 
			6-benzylamine purine (1)</td>
		</tr>
		<tr>
			<td>Caffeine</td>
			<td>SIGMA</td>
			<td>C0750-5G</td>
			<td>STANDARD-5g</td>
		</tr>
		<tr>
			<td>Theobromine</td>
			<td>SIGMA</td>
			<td>T4500</td>
			<td>20 g</td>
		</tr>
		<tr>
			<td>CAMAG TLC Scanner-4</td>
			<td>CAMAG</td>
			<td>27.62</td>
			<td></td>
		</tr>
		<tr>
			<td>WinCATS Planar Chromatography Manager software</td>
			<td>CAMAG</td>
			<td>1.4.10</td>
			<td>Software</td>
		</tr>
		<tr>
			<td>Isoamyl alcohol (24:1)</td>
			<td>SIGMA</td>
			<td>C-0549</td>
			<td>500 mL</td>
		</tr>
		<tr>
			<td>Cyclohexane</td>
			<td>JALMEX</td>
			<td>C4375-13</td>
			<td>1 L</td>
		</tr>
		<tr>
			<td>Acetone</td>
			<td>J.T. BAKER</td>
			<td>900643</td>
			<td>4 L</td>
		</tr>
		<tr>
			<td>Methanol</td>
			<td>J.T. BAKER</td>
			<td>9093-03</td>
			<td>4 L</td>
		</tr>
		<tr>
			<td>Chloroform</td>
			<td>JALMEX</td>
			<td>C-4425-15</td>
			<td>3.5 L</td>
		</tr>
		<tr>
			<td>TLC silica gel 60 F254</td>
			<td>Merck</td>
			<td>1.05554.0001</td>
			<td>TLC plate</td>
		</tr>
		<tr>
			<td>&#946;-mercaptoethanol</td>
			<td>M6250</td>
			<td>SIGMA</td>
			<td>100 mL</td>
		</tr>
		<tr>
			<td>(+)-sodium L- ascorbate</td>
			<td>A4034</td>
			<td>SIGMA</td>
			<td>100 g</td>
		</tr>
		<tr>
			<td>Trizma base</td>
			<td>SIGMA</td>
			<td>T6066</td>
			<td>1 Kg</td>
		</tr>
		<tr>
			<td>Hydrochloric acid 36.5-38%</td>
			<td>J.T. Baker</td>
			<td>9535-05</td>
			<td>2.5 L</td>
		</tr>
		<tr>
			<td>Pierce BCA Protein Assay Kit</td>
			<td>Thermo scientific</td>
			<td>232227</td>
			<td>Kit</td>
		</tr>
		<tr>
			<td>Methyl [3H]-S-adenosyl methionine</td>
			<td>Perkin Elmer</td>
			<td>NET155</td>
			<td>Specific activity of 15 Ci/mmol</td>
		</tr>
		<tr>
			<td>Liquid scintillation vials</td>
			<td>SIGMA</td>
			<td>Z253081</td>
			<td></td>
		</tr>
		<tr>
			<td>Thermostatic bath/circulator</td>
			<td>Cole Parmer</td>
			<td>60714</td>
			<td></td>
		</tr>
		<tr>
			<td>Micro centrifugue tube</td>
			<td>Eppendorf</td>
			<td></td>
			<td>Tube of 1.5 mL</td>
		</tr>
		<tr>
			<td>Cryogenic vials</td>
			<td>Heathrow Scientific</td>
			<td>HS23202A</td>
			<td>2 mL</td>
		</tr>
		<tr>
			<td>Centrifuge 5804</td>
			<td>Eppendorf</td>
			<td>5804 000925</td>
			<td></td>
		</tr>
		<tr>
			<td>Vortex</td>
			<td>Thermolyne</td>
			<td>LR 5947</td>
			<td></td>
		</tr>
		<tr>
			<td>Porcelain mortar</td>
			<td>Fisherbrand</td>
			<td>FB961B</td>
			<td></td>
		</tr>
		<tr>
			<td>Filter paper</td>
			<td>Whatman</td>
			<td>Z274844</td>
			<td>Porosity medium</td>
		</tr>
		<tr>
			<td>Picofuge</td>
			<td>Stratagene</td>
			<td>400550</td>
			<td>2000 x g</td>
		</tr>
		<tr>
			<td>Analytical balance</td>
			<td>AND</td>
			<td>HR-120</td>
			<td>Model HR-120</td>
		</tr>
		<tr>
			<td>Scintillation counter</td>
			<td>Beckman Coulter</td>
			<td>6500</td>
			<td></td>
		</tr>
		<tr>
			<td>Gel photodocumentation system</td>
			<td>Bio-Rad</td>
			<td>Chemic XRS</td>
			<td>Model Chemic XRS</td>
		</tr>
		<tr>
			<td>Compact UV lamp</td>
			<td>UVP</td>
			<td>95002112</td>
			<td>UVGL-25</td>
		</tr>
		<tr>
			<td>Scienceware HDPE Buchner funnel</td>
			<td>SIGMA</td>
			<td>2419907</td>
			<td>Type 37600 mixer</td>
		</tr>
		<tr>
			<td>TRIzol reagent</td>
			<td>Thermo scientific</td>
			<td>15596-018</td>
			<td>200 mL</td>
		</tr>
		<tr>
			<td>ReverdAid Reverse transcriptase</td>
			<td>Thermo scientific</td>
			<td>#EP0441</td>
			<td>10000 U</td>
		</tr>
		<tr>
			<td>Oligo (dT)18 primer</td>
			<td>Thermo scientific</td>
			<td>#S0131</td>
			<td>100 &#181;M</td>
		</tr>
		<tr>
			<td>DNase I, RNase-free</td>
			<td>Thermo scientific</td>
			<td>#EN0525</td>
			<td>1000 U</td>
		</tr>
		<tr>
			<td>Magnesium chloride</td>
			<td>Thermo scientific</td>
			<td>EN0525</td>
			<td>1.25 mL</td>
		</tr>
		<tr>
			<td>Ethylenediaminetetraacetic acid</td>
			<td>Thermo scientific</td>
			<td>EN0525</td>
			<td>1 mL</td>
		</tr>
		<tr>
			<td>dNTP mix</td>
			<td>Thermo scientific</td>
			<td>R0191</td>
			<td>R0191</td>
		</tr>
		<tr>
			<td>SYBR Green qPCR Master Mix (2X)</td>
			<td>Thermo scientific</td>
			<td>K0251</td>
			<td>For 200 reactions of 25 &#181;L</td>
		</tr>
		<tr>
			<td>PikoReal</td>
			<td>Thermo scientific</td>
			<td>2.2</td>
			<td>Software</td>
		</tr>
		<tr>
			<td>Phenol, pH 8.0, equilibrated, Molecular Biology Grade, Ultrapure</td>
			<td>USB</td>
			<td>J75829</td>
			<td>100 mL</td>
		</tr>
		<tr>
			<td>Isopropyl alcohol</td>
			<td>Karal</td>
			<td>2040</td>
			<td>1 L</td>
		</tr>
		<tr>
			<td>Ethyl alcohol</td>
			<td>SIGMA</td>
			<td>64175</td>
			<td>1 L</td>
		</tr>
		<tr>
			<td>Diethyl pyrocarbonate</td>
			<td>SIGMA</td>
			<td>D5758</td>
			<td>100 mL</td>
		</tr>
		<tr>
			<td>Lab Rotator</td>
			<td>LW Scientific</td>
			<td>Mod. LW210</td>
			<td></td>
		</tr>
	</tbody>
</table>

caffeine extraction, enzymatic activity and gene expression of caffeine synthase from plant cell suspensions

Caffeine (1,3,7-trimethylxanthine) is a purine alkaloid present in popular drinks such as coffee and tea. This secondary metabolite is regarded as a chemical defense because it has antimicrobial activity and is considered a natural insecticide. Caffeine can also produce negative allelopathic effects that prevent the growth of surrounding plants. In addition, people around the world consume caffeine for its analgesic and stimulatory effects. Due to interest in the technological applications of caffeine, research on the biosynthetic pathway of this compound has grown. These studies have primarily focused on understanding the biochemical and molecular mechanisms that regulate the biosynthesis of caffeine. In vitro tissue culture has become a useful system for studying this biosynthetic pathway. This article will describe a step-by-step protocol for the quantification of caffeine and for measuring the transcript levels of the gene (CCS1) encoding caffeine synthase (CS) in cell suspensions of C. arabica L. as well as its activity.

Caffeine extracts obtained via the process presented here were analyzed by TLC-densitometry by subjecting the samples to plate chromatography according to the scheme shown in Figure 1. To quantify the levels of caffeine in the cell extracts, a curve with various concentrations of commercial standard for this compound was used (Figure 2A). The pattern of absorbance for caffeine was analyzed in the visible light spectrum (UV-VIS) u...

Watch this Scientific Journal Video about Caffeine Extraction, Enzymatic Activity and Gene Expression of Caffeine Synthase from Plant Cell Suspensions at JoVE.com

Caffeine Extraction, Enzymatic Activity and Gene Expression of Caffeine Synthase from Plant Cell Suspensions

This protocol describes an efficient methodology for the extraction and quantification of caffeine in cell suspensions of C. arabica L. and an experimental process for evaluating the enzymatic activity of caffeine synthase with the expression level of the gene that encodes this enzyme.

Caffeine (1,3,7-trimethylxanthine) is a purine alkaloid present in popular drinks such as coffee and tea. This secondary metabolite is regarded as a ...

This method can help answer key questions in the analytical chemistry, biochemistry and biotechnology fields. Such as, what are the changes that occur in the caffeine biosynthesis. The main advantage of this technique, is that it can be applied to invitro plant models that produces caffeine.To begin, add 10 milliliters of acetone to the lyophilized cells, and seal the flask before mixing with the vortex mixer for 30 seconds. Then, mix the sample at 100 rpm with a rotator for five hours at room temperature. After this, re-suspend the sample with 25 microliters of acetone.First, apply one microliter of the previously prepared caffeine extract to the silica gel plates. Then, develop the TLC in the chromatography chamber with 10 milliliters of the mobile phase, cyclohexane acetone. Visualize the caffeine bands in short wavelength ultraviolet, with a compact UV lamp.After this, quantify caffeine levels by densitometry at 273 nanometers. Using filter paper, vacuum filter the previously prepared cell suspension. Then, use a porcelain mortar to macerate the cell sample, with liquid nitrogen and RNA isolation reagent, until it is homogenized.Next, transfer 500 microliters of the sample to a sterile micro centrifuge tube. Then, add 300 microliters of chloroform isoamyl alcohol, and 300 microliters of equilibrated phenol. Mix the sample with a vortex mixer and centrifuge it at 20, 000G for 15 minutes at four degrees Celsius.After this, transfer 300 microliters of the upper phase to a clean micro centrifuge tube. Then, add 200 microliters of isopropanol and incubate the tube for one hour at negative 20 degrees Celsius. Add one milliliter of ethanol to the pellet.Then, centrifuge the tube at 12, 000G for 10 minutes and decant the liquid phase. Next, dry the sample for 1.5 hours at room temperature. Then, re-suspend the RNA extract with 25 microliters of DEPC-treated water.First, add two micrograms of total RNA extract to a sterile micro centrifuge tube. Then, add one microliter of 10X reaction buffer and one microliter of DNase. Bring the final volume of the reaction to 10 microliters with DEPC-treated water.Then, mix the sample and centrifuge at 2, 000G for one minute. Next, incubate the sample at 37 degrees Celsius for 30 minutes. After this, add one microliter of 50 micromolar disodium ethylene diamine tetraacetate, to stop the reaction.Incubate the sample at 65 degrees Celsius for 10 minutes. Then, apply 100 nanograms of RNA to an agarose gel and run the gel. Visualize the integrity of the RNA using a gel photo documentation system.First, add 2.5 micrograms of total RNA to a micro centrifuge tube. Then, add one microliter of oligo deoxythymidine primer and fill the tube to a final volume of 13 microliters with nuclease-free water. Mix the sample and centrifuge it at 2, 000G for one minute.Incubate the sample at 65 degrees Celsius for five minutes. And then at four degrees Celsius for two minutes. Next, add four microliters of 5X reaction buffer, two microliters of dNTP mix and one microliter of reverse transcriptase to the sample.Then, mix the sample gently and centrifuge at 2, 000G for one minute. After this, incubate the sample at 45 degrees Celsius for 50 minutes, and then at 70 degrees Celsius for 10 minutes. Add 7.5 microliters of 2X Taq DNA polymerase and 0.1 micromoles of RAX, to a PCR micro centrifuge tube.Then, add 0.75 microliters each of forward and reverse primer to amplify the CCS1 gene. After this, add 600 nanograms of CDNA template. Preform the amplification reaction in real time PCR as described in the text protocol.Then, analyze the data with the PCR software. Weigh out one gram of cellular material and pack it in aluminum foil. After macerating the sample, transfer it to a glass vial and add 2.5 milliliters of extraction buffer.Next, centrifuge the sample at 20, 000G for 20 minutes at four degrees Celsius. Transfer 500 microliters aliquots into cryogenic vials. With a spectrophotometer, measure the protein concentration of the sample at 562 nanometers using a bicinchoninic acid assay, with bovine seric albumin as the standard.First, prepare the reaction mixture in a micro centrifuge tube, according to the text protocol. Then, increase the total volume to 200 microliters with 100 millimolar tris HCL. Remember, it is imperative for your own safety to follow proper precautions during preparation of reaction mixture with radioactive material.Keep the micro centrifuge tube on ice and add a volume of the soluble fraction, containing seven to nine milligrams of protein. Then, vortex the mixture and incubate at 30 degrees Celsius for 30 minutes. After this, centrifuge the samples at 11, 000G for five minutes.Then, carefully recover a volume of 900 microliters, and transfer the samples to a scintillation vial. Next, evaporate the chloroform to complete dryness in the hood at room temperature. Add five milliliters of scintillation fluid to the vial.Finally, analyze the radioactivity incorporated into the caffeine using a scintillation counter. In this protocol, the pattern of absorbance for caffeine was analyzed via TLC densitometry, through the visible light spectrum, and reading in maximum absorption at 273 nanometers. The separation curve of caffeine on the TLC plate, showed an RF between 0.34, and 0.39.The RNA derived from suspended cells exhibits clear separations of the 28s, 18s and 5s RRNA subunits, indicating that the samples were of high quality. Finally, a melt curve was obtained from the QPCR analysis, showing a single amplification product for the caffeine synthase gene. After its development, this technique paved the way for researchers in the fields of biotechnology and biochemistry to explore secondary metabolizing tissue culture from coffee, tea and coco.Don't forget that working with radioactivity and molecular pathology can be extremely hazardous, and precautions such as the use of gloves, goggles and special equipment for radioactive material shall always be taken when performing this procedure.

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JoVE Journal

Biochemistry

12.5K Views.  Centro de Investigación Científica de Yucatán. This method can help answer key questions in the analytical chemistry, biochemistry and biotechnology fields. Such as, what are the changes that occur in the caffeine biosynthesis. The main advantage of this technique, is that it can be applied to invitro plant models that produces caffeine.To begin, add 10 milliliters of acetone to the lyophilized cells, and seal the flask before mixing with the vortex mixer for 30 seconds. Then, mix the sample at 100 rpm with a rotator for five hours...