The protocol was adopted from a previous publication11. T. Z., D. Ch., and J. &#268;. were supported by the Ministry of Education, Youth and Sports of the Czech Republic within the National Sustainability Program I (NPU I), grant number LO1415. J. &#268;. was also supported by GA CR, Grant number 18-24397S. Access to instruments and other facilities was supported by the Czech research infrastructure for systems biology C4SYS (project no LM2015055). M. A. S. was supported by a grant from the Russian Science Foundation [no. 14-14-00904].

1. Cyanobacteria Cultivation

<ol>
	<li>Cultivate Synechocystis cells in Erlenmeyer flasks or in photobioreactors10,19 in buffered BG11 medium20 to maintain a pH of &#60; 10 (e.g., using 17 mM HEPES10). 
	NOTE: Standard cultivation conditions require a controlled temperature (typically, 30 &#176;C, the optimal temperature is 35 &#176;C)21, illumination (typical...

<ol>
	<li>Mimuro, M., Kikuchi, H., Green, B. R., Parson, W. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antenna+Systems+and+Energy+Transfer+in+Cyanophyta+and+Rhodophyta.">Antenna Systems and Energy Transfer in Cyanophyta and Rhodophyta.</a> Light-Harvesting Antennas in Photosynthesis. , 281-306 (2003).</li><li>Spear-bernstein, L., Miller, K. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Unique+location+of+the+phycobiliprotein+light-harvesting+pigment+in+the+Cryptophyceae.">Unique location of the phycobiliprotein light-harvesting pigment in the Cryptophyceae.</a> Journal of Phycology. 25 (3), 412-419 (1989).</li><li>Kirst, H., Formighieri, C., Melis, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Maximizing+photosynthetic+efficiency+and+culture+productivity+in+cyanobacteria+upon+minimizing+the+phycobilisome+light-harvesting+antenna+size.">Maximizing photosynthetic efficiency and culture productivity in cyanobacteria upon minimizing the phycobilisome light-harvesting antenna size.</a> Biochimica et Biophysica Acta - Bioenergetics. 1837 (10), 1653-1664 (2014).</li><li>Page, L. E., Liberton, M., Pakrasi, H. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reduction+of+photoautotrophic+productivity+in+the+cyanobacterium+Synechocystis+sp.+strain+PCC+6803+by+phycobilisome+antenna+truncation.">Reduction of photoautotrophic productivity in the cyanobacterium Synechocystis sp. strain PCC 6803 by phycobilisome antenna truncation.</a> Applied and Environmental Microbiology. 78 (17), 6349-6351 (2012).</li><li>Sonani, R. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+advances+in+production,+purification+and+applications+of+phycobiliproteins.">Recent advances in production, purification and applications of phycobiliproteins.</a> World Journal of Biological Chemistry. 7 (1), 100 (2016).</li><li>Bryant, 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=.">.</a> The Molecular Biology of Cyanobacteria. , (1994).</li><li>Kaneko, 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=Sequence+analysis+of+the+genome+of+the+unicellular+cyanobacterium+Synechocystis+sp.+strain+PCC6803.+I.+Sequence+features+in+the+1+Mb+region+from+map+positions+64%+to+92%+of+the+genome.">Sequence analysis of the genome of the unicellular cyanobacterium Synechocystis sp. strain PCC6803. I. Sequence features in the 1 Mb region from map positions 64% to 92% of the genome.</a> DNA Research. 2, 191-198 (1995).</li><li>Kaneko, 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=Sequence+analysis+of+the+genome+of+the+unicellular+cyanobacterium+Synechocystis+sp.+strain+PCC6803.+II.+Sequence+determination+of+the+entire+genome+and+assignment+of+potential+protein-coding+regions.">Sequence analysis of the genome of the unicellular cyanobacterium Synechocystis sp. strain PCC6803. II. Sequence determination of the entire genome and assignment of potential protein-coding regions.</a> DNA Research. 3, 109-136 (1996).</li><li>Grigorieva, G., Shestakov, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transformation+in+the+cyanobacterium+Synechocystis+sp+6803.">Transformation in the cyanobacterium Synechocystis sp 6803.</a> FEMS Microbiology Letters. 13 (4), 367-370 (1982).</li><li>Zav&#345;el, T., Sinetova, M. A., B&#250;zov&#225;, D., Liter&#225;kov&#225;, P., &#268;erven&#253;, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+a+model+cyanobacterium+Synechocystis+sp:+PCC+6803+autotrophic+growth+in+a+flat-panel+photobioreactor.">Characterization of a model cyanobacterium Synechocystis sp: PCC 6803 autotrophic growth in a flat-panel photobioreactor.</a> Engineering in Life Sciences. 15 (1), (2015).</li><li>Zav&#345;el, T., O&#269;en&#225;&#353;ov&#225;, P., &#268;erven&#253;, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Phenotypic+characterization+of+Synechocystis+sp.+PCC+6803+substrains+reveals+differences+in+sensitivity+to+abiotic+stress.">Phenotypic characterization of Synechocystis sp. PCC 6803 substrains reveals differences in sensitivity to abiotic stress.</a> PLoS One. 12 (12), e0189130 (2017).</li><li>Bennett, A., Bogorad, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Complementary+chromatic+adaption+in+a+filamentous+blue-green+alga.">Complementary chromatic adaption in a filamentous blue-green alga.</a> The Journal of Cell Biology. 58, 419-435 (1973).</li><li>L&#252;der, U. H., Knoetzel, J., Wiencke, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Acclimation+of+photosynthesis+and+pigments+to+seasonally+changing+light+conditions+in+the+endemic+antarctic+red+macroalga+Palmaria+decipiens.">Acclimation of photosynthesis and pigments to seasonally changing light conditions in the endemic antarctic red macroalga Palmaria decipiens.</a> Polar Biology. 24 (8), 598-603 (2001).</li><li>Evans, L. V., Lobban, C. S., Chapman, D. J., Kremer, B. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effects+of+spectral+composition+and+irradiance+level+on+pigment+levels+in+seaweeds.">The effects of spectral composition and irradiance level on pigment levels in seaweeds.</a> Experimental Phycology: A Laboratory Manual. , 123-133 (1988).</li><li>Sampath-Wiley, P., Neefus, C. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+improved+method+for+estimating+R-phycoerythrin+and+R-phycocyanin+contents+from+crude+aqueous+extracts+of+Porphyra+(Bangiales,+Rhodophyta).">An improved method for estimating R-phycoerythrin and R-phycocyanin contents from crude aqueous extracts of Porphyra (Bangiales, Rhodophyta).</a> Journal of Applied Phycology. 19 (2), 123-129 (2007).</li><li>Chung, Y. H., Park, Y. M., Moon, Y. J., Lee, E. M., Choi, J. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Photokinesis+of+Cyanobacterium+Synechocystis+sp.+PCC+6803.">Photokinesis of Cyanobacterium Synechocystis sp. PCC 6803.</a> Journal of Photoscience. 11 (3), 89-94 (2004).</li><li>Sun, L., Gault, P. M., Marler, H. J., 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=Phycobilisomes+from+Cyanobacteria.">Phycobilisomes from Cyanobacteria.</a> Handbook on Cyanobacteria: Biochemistry, Biotechnology and Applications. , 105-160 (2009).</li><li>Six, C., 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=Diversity+and+evolution+of+phycobilisomes+in+marine+Synechococcus+spp.:+A+comparative+genomics+study.">Diversity and evolution of phycobilisomes in marine Synechococcus spp.: A comparative genomics study.</a> Genome Biology. 8 (12), (2007).</li><li>Sinetova, M. A., &#268;erven&#253;, J., Zav&#345;el, T., Nedbal, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=On+the+dynamics+and+constraints+of+batch+culture+growth+of+the+cyanobacterium+Cyanothece+sp.+ATCC+51142.">On the dynamics and constraints of batch culture growth of the cyanobacterium Cyanothece sp. ATCC 51142.</a> Journal of Biotechnology. 162 (1), (2012).</li><li>Stanier, R. Y., Kunisawa, R., Mandel, M., Cohen-Bazire, G. <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+properties+of+unicellular+blue-green+algae+(order+Chroococcales).">Purification and properties of unicellular blue-green algae (order Chroococcales).</a> Bacteriological Reviews. 35 (2), 171-205 (1971).</li><li>Zav&#345;el, T., Sinetova, M. A., B&#250;zov&#225;, D., Liter&#225;kov&#225;, P., &#268;erven&#253;, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+a+model+cyanobacterium+Synechocystis+sp.+PCC+6803+autotrophic+growth+in+a+flat-panel+photobioreactor.">Characterization of a model cyanobacterium Synechocystis sp. PCC 6803 autotrophic growth in a flat-panel photobioreactor.</a> Engineering in Life Sciences. 15 (1), 122-132 (2015).</li><li>Hemlata, G., Fareha, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Studies+on+Anabaena+sp.+nccu-9+with+special+reference+to+phycocyanin.">Studies on Anabaena sp. nccu-9 with special reference to phycocyanin.</a> Journal of Algal Biomass Utilization. 2 (1), 30-51 (2011).</li><li>Rito-Palomares, M., Nuez, L., Amador, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Practical+application+of+aqueous+two-phase+systems+for+the+development+of+a+prototype+process+for+c-phycocyanin+recovery+from+Spirulina+maxima.">Practical application of aqueous two-phase systems for the development of a prototype process for c-phycocyanin recovery from Spirulina maxima.</a> Journal of Chemical Technology &amp; Biotechnology. 76 (12), 1273-1280 (2001).</li><li>Zhang, H., 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=Selenium-Containing+Allophycocyanin+Purified+from+Selenium-Enriched+Spirulina+platensis+Attenuates+AAPH-Induced+Oxidative+Stress+in+Human+Erythrocytes+through+Inhibition+of+ROS+Generation.">Selenium-Containing Allophycocyanin Purified from Selenium-Enriched Spirulina platensis Attenuates AAPH-Induced Oxidative Stress in Human Erythrocytes through Inhibition of ROS Generation.</a> Journal of Agricultural and Food Chemistry. 59 (16), 8683-8690 (2011).</li><li>Nedbal, L., Trt&#237;lek, M., Cerven&#253;, J., Kom&#225;rek, O., Pakrasi, H. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+photobioreactor+system+for+precision+cultivation+of+photoautotrophic+microorganisms+and+for+high-content+analysis+of+suspension+dynamics.">A photobioreactor system for precision cultivation of photoautotrophic microorganisms and for high-content analysis of suspension dynamics.</a> Biotechnology and Bioengineering. 100 (5), 902-910 (2008).</li><li>Zav&#345;el, T., Knoop, H., Steuer, R., Jones, P. R., &#268;erven&#253;, J., Trt&#237;lek, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+quantitative+evaluation+of+ethylene+production+in+the+recombinant+cyanobacterium+Synechocystis+sp.+PCC+6803+harboring+the+ethylene-forming+enzyme+by+membrane+inlet+mass+spectrometry.">A quantitative evaluation of ethylene production in the recombinant cyanobacterium Synechocystis sp. PCC 6803 harboring the ethylene-forming enzyme by membrane inlet mass spectrometry.</a> Bioresource Technology. 202, 142-151 (2016).</li><li>Smith, P. K., 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=Measurement+of+protein+using+bicinchoninic+acid.">Measurement of protein using bicinchoninic acid.</a> Analytical Biochemistry. 150 (1), 76-85 (1985).</li><li>Lawrenz, E., Fedewa, E. J., Richardson, T. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Extraction+protocols+for+the+quantification+of+phycobilins+in+aqueous+phytoplankton+extracts.">Extraction protocols for the quantification of phycobilins in aqueous phytoplankton extracts.</a> Journal of Applied Phycology. 23 (5), 865-871 (2011).</li><li>Lea-Smith, D. J., 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=Phycobilisome-Deficient+Strains+of+Synechocystis+sp.+PCC+6803+Have+Reduced+Size+and+Require+Carbon-Limiting+Conditions+to+Exhibit+Enhanced+Productivity.">Phycobilisome-Deficient Strains of Synechocystis sp. PCC 6803 Have Reduced Size and Require Carbon-Limiting Conditions to Exhibit Enhanced Productivity.</a> Plant Physiology. 165 (2), 705-714 (2014).</li><li>Seo, Y. C., 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=Stable+isolation+of+phycocyanin+from+Spirulina+platensis+associated+with+high-pressure+extraction+process.">Stable isolation of phycocyanin from Spirulina platensis associated with high-pressure extraction process.</a> International Journal of Molecular Sciences. 14 (1), 1778-1787 (2013).</li><li>Touloupakis, E., Cicchi, B., Torzillo, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+bioenergetic+assessment+of+photosynthetic+growth+of+Synechocystis+sp.+PCC+6803+in+continuous+cultures.">A bioenergetic assessment of photosynthetic growth of Synechocystis sp. PCC 6803 in continuous cultures.</a> Biotechnology for Biofuels. 8 (1), 133 (2015).</li><li>Touloupakis, E., Cicchi, B., Benavides, A. M. 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This protocol describes a simple, fast, and reproducible method for the quantification of phycobiliprotein content in the model cyanobacterium Synechocystis. Several methods of cell homogenization, protein extraction, and phycocyanin and allophycocyanin quantification are compared, and the final protocol represents a combination of the optimal steps of every single procedure. As representative data, the content of phycobiliproteins was quantified in Synechocystis cells under increasing light intensity. ...

fPhycobiliproteins are water-soluble pigment-protein complexes that represent major components of the light-harvesting antennae in prokaryotic cyanobacteria (Cyanophyta) and several eukaryotic taxa (Glaucophyta, Rhodophyta, and Cryptophyta)1. They occur mainly as supramolecular complexes called phycobilisomes and they are typically attached to the surface of the photosynthetic membranes on the stromal side, with the exception of Cryptophyta, where the phycobiliproteins are localized in the thylakoid lumen2. Four types of phycobiliproteins have been identified up to date: the core allophycocyanin, and the peripheral phycocyanin, phycoerythrin, and phycoerythrocyanin1. As the main light-harvesting complexes, phycobilisomes represent one of the crucial factors of algae and cyanobacteria mass cultures productivity. It has been demonstrated that phycobilisomes truncation can enhance biomass accumulation under strong light3. On the other hand, under modest or low irradiance, the antenna truncation resulted in growth rates and biomass accumulation reduction3,4. Phycobiliproteins are commercially used as food colorants, pharmaceuticals, and food additives, in the cosmetic industry, and as fluorescence probes with applications in flow cytometry, fluorescent immunoassays, and fluorescence microscopy5.
This protocol focuses on the quantitative determination of phycobiliproteins in the model cyanobacterium Synechocystis. Cyanobacteria are the earliest oxygenic photosynthetic autotrophs; they have been forming the Earth&#39;s biosphere for more than 2.4 billion years6. They play a crucial role in global biogeochemical cycles of nitrogen, carbon, oxygen, and other elements. Among cyanobacteria, a unicellular strain Synechocystis gained a unique position since it was the first cyanobacterium with the entire genome sequenced7,8, it is naturally transformable by exogenous DNA9, and it performs stable and relatively fast growth10,11. In Synechocystis, the core antenna component, allophycocyanin, is associated with the integral membrane proteins, and the attached phycocyanin is located on the thylakoid membrane periphery.
Several methods for phycobiliprotein extraction and quantification are compared within this protocol. The final extraction procedure was successfully applied to Synechocystis, as well as to other cyanobacteria strains, including Cyanothece sp., Synechococcuselongatus, Spirulina sp., Arthrospira sp., and Nostoc sp., and it was also successfully applied to red algae Porphyridium cruentum. Therefore, the method developed in this protocol can be considered as a universal method for phycobiliprotein extraction. Even though some of the tested extraction methods resulted in higher total protein yields, the here described extraction procedure provided the highest phycobiliprotein yields together with the lowest content of chlorophyll a residue in the phycobiliprotein extract. Reducing the content of chlorophyll a was essential for the correct phycocyanin and allophycocyanin spectrophotometric quantification.
The phycobiliprotein absorption spectra can vary significantly among various algae and cyanobacteria species12,13,14,15,16,17 and even among several strains of a single cyanobacteria genus18. Therefore, the specific wavelengths and absorption coefficients as used for the determination of phycocyanin and allophycocyanin in Synechocystis are not generally applicable to other strains. Additionally, Synechocystis does not contain phycoerythrin and phycoerythrocyanin that can be found in some other algae and cyanobacteria. For the purpose of the determination of phycobiliproteins in strains other than Synechocystis, it is recommended to evaluate the spectrophotometric equations for each strain individually.
Although the protocol contains two longer steps (overnight freeze-drying of the cellular pellets and 1-hour protein extraction), the total labor time for the phycobiliproteins quantification is no longer than 2 hours.

<table border="0" cellpadding="0" cellspacing="0" style="width:1588px;" width="1587">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:407px;">Synechocystis sp. PCC 6803</td>
			<td style="width:417px;">Institut Pasteur, Paris, France</td>
			<td style="width:137px;">6803</td>
			<td style="width:627px;">Cyanobacterium strain</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Roti-CELL PBS</td>
			<td>Carl Roth GmbH + Co. KG, Karlsruhe, Germany</td>
			<td>9143.1</td>
			<td>Phosphate-Buffered Saline (PBS) solution, pH 7.4</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Eppendorf safe-lock tubes&#160;</td>
			<td style="width:417px;">Eppendorf, Hamburk, Germany</td>
			<td>30120086</td>
			<td>Safe-lock tubes 1.5 ml</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">VWR 80-Place Storage System</td>
			<td style="width:417px;">VWR International, Radnor, Pennsylvania, USA</td>
			<td>30128-282</td>
			<td>Holder for safe-lock tubes&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">RAININ 100 &#181;l -1000 &#181;l&#160;</td>
			<td>Mettler-Toledo, Columbus, Ohio, USA</td>
			<td>17014382</td>
			<td>Pipette</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">GP-LTS-A-1000&#181;L-/F-768/8</td>
			<td>Mettler-Toledo, Columbus, Ohio, USA</td>
			<td>30389272</td>
			<td>Pipette tips</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Rotina 420R</td>
			<td>Hettich, Kirchlengern, Germany</td>
			<td>4701</td>
			<td>Refrigerated centrifuge for 1.5 ml safe-lock tubes and 15 ml conical centrifuge tubes</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">LCexv 4010</td>
			<td>Liebherr, Bulle, Switzerland</td>
			<td>9005382197172</td>
			<td>Refrigerator and freezer -20&#160;&#176;C</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:407px;">Revco ExF -86&#176;C Upright Ultra-Low Temperature Freezer</td>
			<td style="width:417px;">Thermo Fisher Scientific, Waltham, Massachusetts, USA</td>
			<td style="width:137px;">EXF24086V&#160;</td>
			<td>Freezer -80&#160;&#176;C</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">CoolSafe</td>
			<td>LaboGene, Liller&#248;d, Denmark</td>
			<td>7.001.000.615</td>
			<td>Freeze dryer&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">UV-2600</td>
			<td>Shimadzu, Kyoto, Japan</td>
			<td>UV-2600</td>
			<td>Spectrophotometer&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Hellma absorption cuvettes, semi Micro</td>
			<td>Sigma-Aldrich, St. Louis, Missouri, USA</td>
			<td>Z600288&#160;</td>
			<td>VIS/UV-VIS semi-micro cuvettes 0.75-1.5 ml, spectral range 200-2500 nm&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Silamat S6</td>
			<td>Ivoclar Vivadent, Schaan, Liechtenstein</td>
			<td>602286WU</td>
			<td>Homogenizer&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Solid-glass beads</td>
			<td>Sigma-Aldrich, St. Louis, Missouri, USA</td>
			<td>Z273627</td>
			<td>Glass bead of the diameter 2&#160;mm</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">CPA225D-0CE</td>
			<td>Sartorius AG, G&#246;ttingen, Germany</td>
			<td>SECURA225D-1OBR</td>
			<td>Analytical balances</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">C-Phycocyanin from Spirulina sp.&#160;</td>
			<td>Sigma-Aldrich, St. Louis, Missouri, USA</td>
			<td>P2172</td>
			<td>Phycocyanin standard</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Allophycocyanin</td>
			<td>Sigma-Aldrich, St. Louis, Missouri, USA</td>
			<td>A7472</td>
			<td>Allophycocyanin standard</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:407px;">Bicinchoninic Acid Kit&#160;</td>
			<td style="width:417px;">Sigma-Aldrich, St. Louis, Missouri, USA</td>
			<td style="width:137px;">BCA1, B9643</td>
			<td>Complete kit for total proteins determination</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:407px;">AlgaeTron&#160;</td>
			<td style="width:417px;">Photon System Instruments Ltd., Dr&#225;sov, Czech Republic</td>
			<td style="width:137px;">AG 130-ECO&#160;</td>
			<td>Cultivation chamber for E. flasks, with controllable light and atmosphere</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:407px;">Photobioreactor</td>
			<td style="width:417px;">Photon System Instruments Ltd., Dr&#225;sov, Czech Republic</td>
			<td style="width:137px;">FMT-150</td>
			<td>Cultivation equipment for cyanobacteria and algae with completely controllable environment</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Cellometer&#160;</td>
			<td style="width:417px;">Nexcelom Bioscience, Lawrence, Massachusetts, USA</td>
			<td style="width:137px;">Auto M10</td>
			<td>Cell counter</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:407px;">Corning 15 mL centrifuge tubes</td>
			<td style="width:417px;">Sigma-Aldrich, St. Louis, Missouri, USA</td>
			<td style="width:137px;">CLS430791&#160;</td>
			<td>15 ml Centrifuge tube for dry weigth sampling</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:407px;">Herasafe KS</td>
			<td style="width:417px;">Thermo Fisher Scientific, Waltham, Massachusetts, USA</td>
			<td style="width:137px;">51024579</td>
			<td>Laminar flow hood</td>
		</tr>
	</tbody>
</table>

spectrophotometric determination of phycobiliprotein content in cyanobacterium synechocystis

This is a simple protocol for the quantitative determination of phycobiliprotein content in the model cyanobacterium Synechocystis. Phycobiliproteins are the most important components of phycobilisomes, the major light-harvesting antennae in cyanobacteria and several algae taxa. The phycobilisomes of Synechocystis contain two phycobiliproteins: phycocyanin and allophycocyanin. This protocol describes a simple, efficient, and reliable method for the quantitative determination of both phycocyanin and allophycocyanin in this model cyanobacterium. We compared several methods of phycobiliprotein extraction and spectrophotometric quantification. The extraction procedure as described in this protocol was also successfully applied to other cyanobacteria strains such as Cyanothece sp., Synechococcuselongatus, Spirulina sp., Arthrospira sp., and Nostoc sp., as well as to red algae Porphyridium cruentum. However, the extinction coefficients of specific phycobiliproteins from various taxa can differ and it is, therefore, recommended to validate the spectrophotometric quantification method for every single strain individually. The protocol requires little time and can be performed in any standard life science laboratory since it requires only standard equipment.

For the initial method tests, Synechocystis was cultivated as batch cultures in Erlenmeyer flasks on a shaker in BG11 cultivation medium20 (supplemented with 17 mM HEPES) at 25 &#176;C, under a warm white light of an intensity of 50 &#181;mol(photons)/(m2&#183;s) and with 1% CO2 in the culturing atmosphere. During the cultivation, the cultures were sampled to safe-lock tubes and centrifuged (15,000 x g at laboratory temperatu...

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Spectrophotometric Determination of Phycobiliprotein Content in Cyanobacterium Synechocystis

Here, we present a protocol to quantitatively determine phycobiliprotein content in the cyanobacterium Synechocystis using a spectrophotometric method. The extraction procedure was also successfully applied to other cyanobacteria and algae strains; however, due to variations in pigment absorption spectra, it is necessary to test the spectrophotometric equations for each strain individually.

Spectrophotometric Determination of Phycobiliprotein Content in Cyanobacterium Synechocystis

This is a simple protocol for the quantitative determination of phycobiliprotein content in the model cyanobacterium Synechocystis. Phycobiliproteins are ...

The overall goal of this protocol is to quantitatively determine the phycobiliproteins content in the model cyanobacterium Synechocystis using a spectrophotometric method. Phycobiliproteins are water soluble pigment-protein complexes that represent major components of the light-harvesting antennae in prokaryotic cyanobacteria and several groups of eukaryotic algae. Since they are the main light-harvesting complexes, phycobiliproteins represent one of the crucial factors that determine algae and cyanobacteria productivity.Synechocystis is a model cyanobacterium which is used in hundreds of laboratories worldwide. Synechocystis contains two phycobiliproteins, phycocyanin and allophycocyanin. This protocol describes simple, efficient and reliable method for quantitative determination of both phycobiliproteins in this mold strain.We compared several methods, phycobiliproteins extraction and spectrophotometric quantification. The quantification method needs to be tested for every single strain since phycobiliproteins absorption spectra can vary between different strains. On the beginning of the phycobiliproteins extraction, transfer one milliliter of cyanobacterium culture to a safe-lock tube.If you decide to determine dry weight of the samples, weight the empty tubes before the culture sampling. Be sure that the culture is not sedimented. Centrifuge the cells at 15, 000 G at laboratory temperature for five minutes.Carefully discard the supernatant. Be sure to not disturb the pellet. Put the samples to freezer.For long-term storage, keep the samples at 80 degrees Celsius. This is necessary to prevent phycobiliproteins degradation. Once the samples are frozen, insert them into the freeze dryer.Once the freeze drying has started, check the temperature and pressure on the freeze dryer. The temperature has to be below 60 degrees Celsius and the pressure has to be around one hectare Pascal. Freeze dry the samples overnight.After finishing the freeze drying cycle, close the tubes as soon as possible to prevent reabsorption of water from air. Add four PCs of two milliliter glass beads to each sample tube. Homogenize the samples with the glass beads for 15 seconds.Properly homogenized sample is spread over the whole inner surface of the safe-lock tubes. After cells homogenization, add one milliliter of phosphate-buffered saline to the samples in order to extract the phycobiliproteins. Optimal pH of the PBS is around 7.4.Mix the cells with the PBS for five seconds on the homogenizer. This will secure optimal sample mixing for efficient phycobiliproteins extraction. After mixing, the samples are greenish.Keep the samples on ice for 60 minutes for the most efficient phycobiliproteins extraction. After the extraction, centrifuge the samples at 15, 000 G and four degrees Celsius for five minutes. After centrifugation, the supernatant has cyan blue color.Before the spectrophotometric measurement, calibrate the spectrophotometer using the PBS as a blank. Once the spectrophotometer is calibrated discarded PBS from one spectrophotometer cuvette and pipette the supernatant with extracted phycobiliproteins instead of the discarded buffer. For phycocyanin and allophycocyanin quantification the supernatant with extracted phycobiliproteins is measured at 615, 652 and 720 nanometers.As described in the text, there are several equations for the phycobilisomes quantification known in the literature. The equation used in this protocol was found as the best correlating phycocyanin and allophycocyanin concentrations as the pigments and dots. Critical steps of the protocol are cells homogenization and extraction, that should provide both high yield and high specificity.We tested several extraction procedures such as cells disruption by sonication, homogenization with zirconia beads, or freeze cell link. The method from this protocol provided the highest phycobilisomes yield. Since even a small contamination of the protein extract by chlorophyll can lead to the phycobiliproteins content overestimation, it is necessary to avoid any chlorophyll extraction from the cells.We detected chlorophyll in the crude extract, then we used sonication for cells disruption. With repeating sonication cycles, chlorophyll concentration increased. Homogenization time was optimized as 15 seconds.Homogenization for both five seconds and 20 seconds provided slightly lower yields. Addition of sodium or potassium chloride to the PBS buffer or to water, did not increase phycobiliproteins extraction efficiency, same as extraction in sodium acetate buffer. The phycobiliproteins extraction time was optimized for 60 minutes, since after 120 and even 240 minutes, the phycobiliproteins concentration didn't change significantly.Make sure that absorbance at 615, 652 and 720 nanometers fit into the near absorbance range of the spectrophotometer. The spectrophotometer used in this protocol show the near absorbance range between 0.1 and three. We compared several equations of spectrophotometric phycobiliproteins quantification known from the literature.The equation of Bennett and Bogorad provided the best reconstruction of both phycocyanin and allophycocyanin content in the pigment standards with known protein concentrations. The differences between the individual equations are connected with variations in phycobiliproteins extinction coefficients of the specific organism. The use of streptomycin sulfate didn't lead to reduction of chlorophyll A in samples where sonication was applied or avoided.As the representative data, we determined content of phycobiliproteins in Synechocystis cells. Phycobiliproteins content decreased under increasing light. The protocol was established to minimize time and equipment requirements for the written pigment analysis that can be performed in any standard live-science laboratory.Also, the protocol contains two other steps, such as freeze drying of the cell pellet and proteins extraction. The total labor time for the phycobilisomes quantification is no longer than two hours.

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JoVE Journal

Biochemistry

14.9K 조회수.  Czech Academy of Sciences. The overall goal of this protocol is to quantitatively determine the phycobiliproteins content in the model cyanobacterium Synechocystis using a spectrophotometric method. Phycobiliproteins are water soluble pigment-protein complexes that represent major components of the light-harvesting antennae in prokaryotic cyanobacteria and several groups of eukaryotic algae. Since they are the main light-harvesting complexes, phycobiliproteins represent one of the crucial factors that determine algae a...