Name: natural transformation, protein expression, and cryoconservation of the filamentous cyanobacterium phormidium lacuna
Uploaded: 2022-02-01T14:30:00
Description: Watch this Scientific Journal Video about Natural Transformation, Protein Expression, and Cryoconservation of the Filamentous Cyanobacterium Phormidium lacuna at JoVE.com

The work was supported by the Karlsruher Institute of Technology.

1. Isolation from the natural environment
NOTE: Green algae, diatoms, filamentous cyanobacteria, and other microalgae can be isolated. The protocol can be used for any microalga species from rockpools growing under laboratory conditions. Filamentous cyanobacteria that belong to Oscillatoriales can be easily recognized by their movement and filamentous shape. The species can be identified in a semipure state by genome sequencing or 16S rRNA sequencing.
<ol>
	<li>Transfer liqu...

<ol>
	<li>Brasil, B., de Siqueira, F. G., Salum, T. F. C., Zanette, C. M., Spier, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microalgae+and+cyanobacteria+as+enzyme+biofactories.">Microalgae and cyanobacteria as enzyme biofactories.</a> Algal Research-Biomass Biofuels and Bioproducts. 25, 76-89 (2017).</li><li>Gundolf, R., Oberleitner, S., Richter, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluation+of+New+Genetic+Toolkits+and+Their+Role+for+Ethanol+Production+in+Cyanobacteria.">Evaluation of New Genetic Toolkits and Their Role for Ethanol Production in Cyanobacteria.</a> Energies. 12 (18), 3515 (2019).</li><li>Wendt, K. E., 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=Genomics+approaches+to+deciphering+natural+transformation+in+cyanobacteria.">Genomics approaches to deciphering natural transformation in cyanobacteria.</a> Frontiers in Microbiology. 10, 1259 (2019).</li><li>Tandeau de Marsac, N., 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+new+approach+for+molecular+cloning+in+cyanobacteria:+cloning+of+an+Anacystis+nidulans+met+gene+using+a+Tn901-induced+mutant.">A new approach for molecular cloning in cyanobacteria: cloning of an Anacystis nidulans met gene using a Tn901-induced mutant.</a> Gene. 20 (1), 111-119 (1982).</li><li>Porter, R. D. <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+cyanobacteria.">Transformation in cyanobacteria.</a> Critical Reviews in Microbiology. 13 (2), 111-132 (1986).</li><li>Joset, F. <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+Synechocystis+PCC+6714+and+6803:+preparation+of+chromosomal+DNA.">Transformation in Synechocystis PCC 6714 and 6803: preparation of chromosomal DNA.</a> Methods in Enzymology. 167, 712-714 (1988).</li><li>Tsinoremas, N. F., Kutach, A. K., Strayer, C. A., Golden, S. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficient+gene+transfer+in+Synechococcus+sp+strains+PCC-7942+and+PCC-6301+by+interspecies+conjugation+and+chromosomal+recombination.">Efficient gene transfer in Synechococcus sp strains PCC-7942 and PCC-6301 by interspecies conjugation and chromosomal recombination.</a> Journal of Bacteriology. 176 (21), 6764-6768 (1994).</li><li>Matsunaga, T., Takeyama, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genetic+engineering+in+marine+cyanobacteria.">Genetic engineering in marine cyanobacteria.</a> Journal of Applied Phycology. 7 (1), 77-84 (1995).</li><li>Frigaard, N. U., Sakuragi, Y., 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=Gene+inactivation+in+the+cyanobacterium+Synechococcus+sp.+PCC+7002+and+the+green+sulfur+bacterium+Chlorobium+tepidum+using+in+vitro-made+DNA+constructs+and+natural+transformation.">Gene inactivation in the cyanobacterium Synechococcus sp. PCC 7002 and the green sulfur bacterium Chlorobium tepidum using in vitro-made DNA constructs and natural transformation.</a> Methods in Molecular Biology. 274, 325-340 (2004).</li><li>Iwai, M., Katoh, H., Katayama, M., Ikeuchi, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Improved+genetic+transformation+of+the+thermophilic+cyanobacterium,+Thermosynechococcus+elongatus+BP-1.">Improved genetic transformation of the thermophilic cyanobacterium, Thermosynechococcus elongatus BP-1.</a> Plant and Cell Physiology. 45 (2), 171-175 (2004).</li><li>Vioque, A., Leon, R., Galvan, A., Fernandez, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transformation+of+cyanobacteria.">Transformation of cyanobacteria.</a> Transgenic Microalgae as Green Cell. , 12-22 (2007).</li><li>Nies, F., Mielke, M., Pochert, J., Lamparter, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Natural+transformation+of+the+filamentous+cyanobacterium+Phormidium+lacuna.">Natural transformation of the filamentous cyanobacterium Phormidium lacuna.</a> Plos One. 15 (6), 0234440 (2020).</li><li>Ravindran, C. R. M., Suguna, S., Shanmugasundaram, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electroporation+as+a+tool+to+transfer+the+plasmid+pRL489+in+Oscillatoria+MKU+277.">Electroporation as a tool to transfer the plasmid pRL489 in Oscillatoria MKU 277.</a> Journal of Microbiological Methods. 66 (1), 174-176 (2006).</li><li>El Semary, N. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optimized+electroporation-induced+transformation+in+Microcystis+aeruginosa+PCC7806.">Optimized electroporation-induced transformation in Microcystis aeruginosa PCC7806.</a> Biotechnologie Agronomie Societe et Environnement. 14 (1), 149-152 (2010).</li><li>Nies, F., Mielke, M., Pochert, J., Lamparter, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Natural+transformation+of+the+filamentous+cyanobacterium+Phormidium+lacuna.">Natural transformation of the filamentous cyanobacterium Phormidium lacuna.</a> PLoS One. 15 (6), 0234440 (2020).</li><li>Sode, K., Tatara, M., Takeyama, H., Burgess, J. G., Matsunaga, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Conjugative+gene-transfer+in+marine+cyanobacteria+-+Synechococcus+Sp,+Synechocystis+Sp+and+Pseudanabaena+Sp.">Conjugative gene-transfer in marine cyanobacteria - Synechococcus Sp, Synechocystis Sp and Pseudanabaena Sp.</a> Applied Microbiology and Biotechnology. 37 (3), 369-373 (1992).</li><li>Stucken, K., Ilhan, J., Roettger, M., Dagan, T., Martin, W. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transformation+and+conjugal+transfer+of+foreign+gGenes+into+the+filamentous+multicellular+cyanobacteria+(Subsection+V)+Fischerella+and+Chlorogloeopsis.">Transformation and conjugal transfer of foreign gGenes into the filamentous multicellular cyanobacteria (Subsection V) Fischerella and Chlorogloeopsis.</a> Current Microbiology. 65 (5), 552-560 (2012).</li><li>Bellali, S., Khalil, J. B., Fontanini, A., Raoult, D., Lagier, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+protectant+medium+preserving+bacterial+viability+after+freeze+drying.">A new protectant medium preserving bacterial viability after freeze drying.</a> Microbiological Research. 236, 126454 (2020).</li><li>Wallner, T., Pedroza, L., Voigt, K., Kaever, V., Wilde, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+cyanobacterial+phytochrome+2+regulates+the+expression+of+motility-related+genes+through+the+second+messenger+cyclic+di-GMP.">The cyanobacterial phytochrome 2 regulates the expression of motility-related genes through the second messenger cyclic di-GMP.</a> Photochemical &amp; Photobiological Sciences. 19 (5), 631-643 (2020).</li><li>Wilde, A., Fiedler, B., Borner, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+cyanobacterial+phytochrome+Cph2+inhibits+phototaxis+towards+blue+light.">The cyanobacterial phytochrome Cph2 inhibits phototaxis towards blue light.</a> Molecular Microbiology. 44 (4), 981-988 (2002).</li><li>Bhaya, D., Takahashi, A., Grossman, A. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Light+regulation+of+type+IV+pilus-dependent+motility+by+chemosensor-like+elements+in+Synechocystis+PCC6803.">Light regulation of type IV pilus-dependent motility by chemosensor-like elements in Synechocystis PCC6803.</a> Proceedings of the National Academy of Sciences of the United States of America. 98 (13), 7540-7545 (2001).</li><li>Guillard, R. R., Ryther, J. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Studies+of+marine+planktonic+diatoms.+I.+Cyclotella+nana+Hustedt,+and+Detonula+confervacea+(cleve)+Gran.">Studies of marine planktonic diatoms. I. Cyclotella nana Hustedt, and Detonula confervacea (cleve) Gran.</a> Canadian Journal of Microbiology. 8, 229-239 (1962).</li><li>Kester, D. R., Duedall, I. W., Connors, D. N., Pytkowicz, R. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preparation+of+artificial+seawater.">Preparation of artificial seawater.</a> Limnology and Oceanography. 12 (1), 176-179 (1967).</li><li>Sambrook, J., Russell, D. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Molecular Cloning. A Laboratory Manual. 3rd edition. , (2001).</li><li>Cold Spring Harbor Protocols. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CTAB+DNA+extraction+buffer.">CTAB DNA extraction buffer.</a> Cold Spring Harbor Protocols. 2009 (3), (2009).</li><li>Singh, S. P., Rastogi, R. P., H&#228;der, D. -. P., Sinha, R. P. <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+genomic+DNA+extraction+from+cyanobacteria.">An improved method for genomic DNA extraction from cyanobacteria.</a> World Journal of Microbiology &amp; Biotechnology. 27, 1225-1230 (2011).</li><li>French, C. S., Milner, H. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Disintegration+of+bacteria+and+small+particles+by+high-pressure+extrusion.">Disintegration of bacteria and small particles by high-pressure extrusion.</a> Methods in Enzymology. 1, 64-67 (1955).</li><li>Sambrook, J., Fritsch, E. F., Maniatis, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Molecular cloning, a laboratory manual. 2nd ed. , (1989).</li><li>Lamparter, 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=The+involvement+of+type+IV+pili+and+phytochrome+in+gliding+motility,+lateral+motility+and+phototaxis+of+the+cyanobacterium+Phormidium+lacuna.">The involvement of type IV pili and phytochrome in gliding motility, lateral motility and phototaxis of the cyanobacterium Phormidium lacuna.</a> bioRxiv. , (2021).</li><li>Nies, F., 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=Characterization+of+Phormidium+lacuna+strains+from+the+North+Sea+and+the+Mediterranean+Sea+for+biotechnological+applications.">Characterization of Phormidium lacuna strains from the North Sea and the Mediterranean Sea for biotechnological applications.</a> Process Biochemistry. 59, 194-206 (2017).</li><li>Kachel, B., Mack, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Engineering+of+Synechococcus+sp.+strain+PCC+7002+for+the+photoautotrophic+production+of+light-sensitive+riboflavin+(vitamin+B2).">Engineering of Synechococcus sp. strain PCC 7002 for the photoautotrophic production of light-sensitive riboflavin (vitamin B2).</a> Metabolic Engineering. 62, 275-286 (2020).</li><li>Lukavsky, J., Cepak, V., Komarek, J., Kasparkova, M., Takacova, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Catalogue+of+algal+and+cyanobacterial+strains+of+culture+collection+of+autotrophic+organisms+at+Trebon.">Catalogue of algal and cyanobacterial strains of culture collection of autotrophic organisms at Trebon.</a> Algological Studies. 63, 59-112 (1992).</li><li>Philbrick, J. B., Diner, B. A., Zilinskas, B. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Construction+and+characterization+of+cyanobacterial+mutants+lacking+the+manganese-stabilizing+polypeptide+of+photosystem-ii.">Construction and characterization of cyanobacterial mutants lacking the manganese-stabilizing polypeptide of photosystem-ii.</a> Journal of Biological Chemistry. 266 (20), 13370-13376 (1991).</li><li>Pinevich, A. V., Veprritskii, A. A., Gromov, B. V., Krautvald, K., Titova, N. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cellular+and+cultural+properties+and+characterization+of+the+pigment+in+Nostoc+sp,+a+cyanobacterium+unusually+rich+in+c-phycoerythrin.">Cellular and cultural properties and characterization of the pigment in Nostoc sp, a cyanobacterium unusually rich in c-phycoerythrin.</a> Microbiology. 63 (5), 481-485 (1994).</li><li>Schlosser, U. G., Friedl, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Additions+to+the+culture+collection+of+algae+at+Gottingen+since+1997.">Additions to the culture collection of algae at Gottingen since 1997.</a> Nova Hedwigia. 71 (1-2), 243-262 (2000).</li><li>Takano, H., Arai, T., Hirano, M., Matsunaga, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+intensity+and+quality+of+light+on+phycocyanin+production+by+a+marine+cyanobacterium+Synechococcus+sp.+042902.">Effects of intensity and quality of light on phycocyanin production by a marine cyanobacterium Synechococcus sp. 042902.</a> Applied Microbiology and Biotechnology. 43 (6), 1014-1018 (1995).</li><li>Carrer, H., Hockenberry, T. N., Svab, Z., Maliga, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Kanamycin+resistance+as+a+selectable+marker+for+plastid+transformation+in+tobacco.">Kanamycin resistance as a selectable marker for plastid transformation in tobacco.</a> Molecular and General Genetics: MGG. 241 (1-2), 49-56 (1993).</li><li>Kaulen, H., Schell, J., Kreuzaler, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Light-induced+expression+of+the+chimeric+chalcone+synthase-NptII+gene+in+tobacco+cells.">Light-induced expression of the chimeric chalcone synthase-NptII gene in tobacco cells.</a> EMBO Journal. 5 (1), 1-8 (1986).</li><li>Cotlet, M., Goodwin, P. M., Waldo, G. S., Werner, J. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+comparison+of+the+fluorescence+dynamics+of+single+molecules+of+a+green+fluorescent+protein:+One-+versus+two-photon+excitation.">A comparison of the fluorescence dynamics of single molecules of a green fluorescent protein: One- versus two-photon excitation.</a> Chemphyschem. 7 (1), 250-260 (2006).</li><li>Taton, A., 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=The+circadian+clock+and+darkness+control+natural+competence+in+cyanobacteria.">The circadian clock and darkness control natural competence in cyanobacteria.</a> Nature Communications. 11 (1), 1688 (2020).</li></ol>

Although many strains of cyanobacteria are available from culture collections32,33,34,35,36, there is still a demand for new cyanobacteria from the wild because these species are adapted to specific properties. P. lacuna was collected from rockpools and is adapted to variations of salt concentrations and temperature30. Strains ...

Cyanobacteria are prokaryotic organisms that utilize photosynthesis as an energy source1,2. Research is increasingly focused on cyanobacterial species. Several cyanobacteria can be transformed with DNA3. Genes can be knocked out or overexpressed in these species. However, transformation is restricted to a few species4,5,6,7,8,9,10,11, and it can be difficult to establish transformation in strains from culture collections or the wild8. Strains of the filamentous species Phormidium lacuna (Figure 1) were isolated from marine rockpools, in which environmental conditions, such as salt concentrations or temperature, fluctuate over time. These filamentous cyanobacteria can be used as model organisms for the order Oscillatoriales12 to which they belong.
During trials testing gene transfer by electroporation13,14&#160;it was found that P. lacuna can be transformed by natural transformation15. In this process, DNA is taken up naturally by some cells. Compared to other methods of transformation16,17, natural transformation has the advantage of not requiring additional tools that could complicate the procedure. For example, electroporation requires proper cuvettes, intact wires, and selection of the proper voltage. P. lacuna is presently the only Oscillatoriales member susceptible to natural transformation. Because the original protocol is based on electroporation protocols, it still included several washing steps that might be unnecessary. Different approaches were tested to simplify the protocol, leading to the transformation protocol presented here.
The genome sequence is essential for further molecular studies based on gene knockout or overexpression. Although genome sequences can be obtained with next-generation sequencing machines within short periods, the extraction of DNA can be difficult and depends on the species. With P. lacuna, several protocols were tested. A modified cetyl trimethyl ammonium bromide (CTAB)-based method was then established, resulting in acceptable purity of DNA and DNA yields of each purification cycle for continued work in the laboratory. The genome of five strains could be sequenced with this protocol. The next logical transformation step was to establish protein expression in P. lacuna.
The sfGFP used as a marker protein in this protocol can be detected with any fluorescence microscope. All promoters that were tested could be used for P. lacuna sfGFP expression. The increasing number of strains arising from transformation has resulted in the need for a method for storing the cultures. Such methods are established for Escherichia coli and many other bacteria18. In standard protocols, glycerol cultures are prepared, transferred in liquid nitrogen, and stored at -80 &#176;C. This method requires only a few steps and is highly reliable for those species for which it is established. The standard protocol was not feasible for P. lacuna because living cells could not be recovered in all cases. However, when glycerol was removed after thawing, cells of all trials survived. Simple methods are presented for the analysis of motility of P. lacuna, which can be combined with knockout mutagenesis to investigate type IV pili or the role of photoreceptors. These assays are different from those of single-celled cyanobacteria19,20,21 and can also be useful for other Oscillatoria.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Autoclave 3870 ELV</td>
			<td>Tuttnauer</td>
			<td>3870 ELV</td>
			<td></td>
		</tr>
		<tr>
			<td>Bacto Agar</td>
			<td>OttoNorwald</td>
			<td>214010</td>
			<td></td>
		</tr>
		<tr>
			<td>BG-11 Freshwater Solution</td>
			<td>Sigma Aldrich</td>
			<td>C3061</td>
			<td></td>
		</tr>
		<tr>
			<td>BG-11 medium</td>
			<td>Merck</td>
			<td>73816-250ML</td>
			<td></td>
		</tr>
		<tr>
			<td>Boric acid</td>
			<td>Merck</td>
			<td>10043-35-3</td>
			<td>H3BO3</td>
		</tr>
		<tr>
			<td>Calcium chloride dihydrate</td>
			<td>Carl Roth</td>
			<td>10035-04-8</td>
			<td>CaCl2 &#183; 2 H2O</td>
		</tr>
		<tr>
			<td>Cell culture flasks Cellstar with filter screw cap, sterile, 250 mL</td>
			<td>Greiner</td>
			<td>658190</td>
			<td></td>
		</tr>
		<tr>
			<td>Cell culture flasks Cellstar with filter screw cap, sterile, 50 mL</td>
			<td>Greiner</td>
			<td>601975</td>
			<td></td>
		</tr>
		<tr>
			<td>Centrifuge LYNX 4000</td>
			<td>Thermo Scientific</td>
			<td>75006580</td>
			<td>and rotor</td>
		</tr>
		<tr>
			<td>Centrifuge microstar 17</td>
			<td>VWR International</td>
			<td>N/A</td>
			<td>for up to 13,000 rpm</td>
		</tr>
		<tr>
			<td>Cetyltrimethylammonium Bromide (CTAB)</td>
			<td>PanReac AppliChem</td>
			<td>57-09-0</td>
			<td>C19H42BrN</td>
		</tr>
		<tr>
			<td>Chloroform : Isoamyl Alcohol 24 : 1</td>
			<td>PanReac AppliChem</td>
			<td> 
			A1935</td>
			<td></td>
		</tr>
		<tr>
			<td>Cobalt(II) chloride hexahydrate</td>
			<td>Merck</td>
			<td>7791-13-1</td>
			<td>CoCl2 &#183; 6 H2O</td>
		</tr>
		<tr>
			<td>Copper(II) sulphate pentahydrate</td>
			<td>Merck</td>
			<td>7758-99-8</td>
			<td>&#160;CuSO4 &#183; 5 H2O</td>
		</tr>
		<tr>
			<td>D(+)-Biotin</td>
			<td>Carl Roth</td>
			<td>58-85-5</td>
			<td>&#160;C10H16N2O3S</td>
		</tr>
		<tr>
			<td>DNA ladder 1 kb</td>
			<td>New England Biolabs</td>
			<td>N3232</td>
			<td></td>
		</tr>
		<tr>
			<td>DNA ladder 100 bp</td>
			<td>New England Biolabs</td>
			<td>N3231</td>
			<td></td>
		</tr>
		<tr>
			<td>Electrical pipetting help accujet-pro S</td>
			<td>Brand GmbH</td>
			<td>26360</td>
			<td>for pipetting 1-25 mL</td>
		</tr>
		<tr>
			<td>Ethanol</td>
			<td>VWR</td>
			<td>64-17-5</td>
			<td>C2H6O</td>
		</tr>
		<tr>
			<td>Ethylenediamine tetraacetic acid disodium salt dihydrate</td>
			<td>Carl Roth</td>
			<td>6381-92-6</td>
			<td>EDTA-Na2 &#183; 2 H2O</td>
		</tr>
		<tr>
			<td>Fluorescence microscope ApoTome</td>
			<td>Zeiss</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Fluorescence microscope Axio Imager 2</td>
			<td>Zeiss</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>French Pressure Cell Press</td>
			<td>American Instrument Company</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Gel documation System Saffe Image</td>
			<td>Invitrogen</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Gelelctrophoresis system Mupid-One/-exu</td>
			<td>ADVANCED</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Glassware, different</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Glycerol</td>
			<td>Carl Roth</td>
			<td>56-81-5</td>
			<td>C3H8O3</td>
		</tr>
		<tr>
			<td>Iron(III) chloride hexahydrate</td>
			<td>Merck</td>
			<td>10025-77-1</td>
			<td>&#160;FeCl3 &#183; 6 H2O</td>
		</tr>
		<tr>
			<td>Kanamycin</td>
			<td>Sigma-Aldrich</td>
			<td>25389-94-0</td>
			<td></td>
		</tr>
		<tr>
			<td>Kanamycin sulphate</td>
			<td>Carl Roth</td>
			<td>25389-94-0</td>
			<td>C18H36N4O11 &#183; H2SO4</td>
		</tr>
		<tr>
			<td>Lauroylsarcosine, Sodium Salt (Sarcosyl)</td>
			<td>Sigma Aldrich</td>
			<td>137-16-6</td>
			<td>C15H28NO3 &#183; Na</td>
		</tr>
		<tr>
			<td>LB Broth (Lennox)</td>
			<td>Carl Roth</td>
			<td>X964.4</td>
			<td></td>
		</tr>
		<tr>
			<td>Light source, fluorescent tube L18W/954 daylight</td>
			<td>OSRAM</td>
			<td></td>
			<td>cultivation of cyanobacteria</td>
		</tr>
		<tr>
			<td>Light source, LED panel XL 6500K 140 W</td>
			<td>Bloom Star</td>
			<td>N/A</td>
			<td>cultivation of cyanobacteria, up to 1,000 &#181;mol m-2 s-1</td>
		</tr>
		<tr>
			<td>Magnesium chloride hexahydrate</td>
			<td>Carl Roth</td>
			<td>7791-18-6</td>
			<td>MgCl2 &#183; 6 H2O</td>
		</tr>
		<tr>
			<td>Manganese(II) chloride tetrahydrate</td>
			<td>Serva</td>
			<td>13446-34-9</td>
			<td>MnCl2 &#183; 4 H2O</td>
		</tr>
		<tr>
			<td>Microscope DM750</td>
			<td>Zeiss</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Midi prep plasmid extraction kit NucleoBond Xtra Midi kit</td>
			<td>Macherey-NAGEL GmbH &#38; Co. KG</td>
			<td>REF740410.50</td>
			<td></td>
		</tr>
		<tr>
			<td>Minicomputer Raspberry Pi 4 +</td>
			<td>Conrad Electronics</td>
			<td>2138863-YD</td>
			<td>for time-lapse recording</td>
		</tr>
		<tr>
			<td>Ocular camera EC3</td>
			<td>Leica</td>
			<td></td>
			<td>for continuous recording up to 30 s</td>
		</tr>
		<tr>
			<td>Ocular camera MikrOkular Full HD</td>
			<td>Bresser</td>
			<td></td>
			<td>for time-lapse recordings, coupled to Raspberry Pi minicomputer</td>
		</tr>
		<tr>
			<td>Petri dishes polystyrole, 100 mm x 20 mm</td>
			<td>Merck</td>
			<td>P5606-400EA</td>
			<td></td>
		</tr>
		<tr>
			<td>Petri dishes polystyrole, 60 mm x 15 mm</td>
			<td>Merck</td>
			<td>P5481-500EA</td>
			<td></td>
		</tr>
		<tr>
			<td>Photometer Nanodrop ND-1000</td>
			<td>Peqlab Biotechnologie</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Photometer Uvikon XS</td>
			<td>Goebel Instrumentelle Analytik GmbH</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Pipetman 100-1,000 &#181;L</td>
			<td>Gilson</td>
			<td>SKU: FA10006M</td>
			<td></td>
		</tr>
		<tr>
			<td>Pipetman 10-100 &#181;L</td>
			<td>Gilson</td>
			<td>SKU: FA10004M</td>
			<td></td>
		</tr>
		<tr>
			<td>Plastic pipettes 10 mL, sterile</td>
			<td>Greiner</td>
			<td>607107</td>
			<td></td>
		</tr>
		<tr>
			<td>Plastic tube, sterile, 15 mL</td>
			<td>Greiner</td>
			<td>188271</td>
			<td></td>
		</tr>
		<tr>
			<td>Plastic tube, sterile, 50 mL</td>
			<td>Greiner</td>
			<td>227261</td>
			<td></td>
		</tr>
		<tr>
			<td>Potassium bromide</td>
			<td>Carl Roth</td>
			<td>7758-02-3</td>
			<td>KBr</td>
		</tr>
		<tr>
			<td>Potassium chloride</td>
			<td>Carl Roth</td>
			<td>7447-40-7</td>
			<td>KCl</td>
		</tr>
		<tr>
			<td>Power supply Statron 3252-1</td>
			<td>Statron Ger&#228;tetechnik GmbH</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Power supply Voltcraft PPS 16005</td>
			<td>Conrad Electronics</td>
			<td></td>
			<td>for LED</td>
		</tr>
		<tr>
			<td>Proteinase K</td>
			<td>Promega</td>
			<td>MC500C</td>
			<td>from Maxwell 16 miRNA Tissue Kit AS1470</td>
		</tr>
		<tr>
			<td>Q5 polymerase</td>
			<td>New England Biolabs</td>
			<td>M0491S</td>
			<td></td>
		</tr>
		<tr>
			<td>Sequencing kit NextSeq 500/550 v2.5</td>
			<td>Illumina</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Sequencing system NextSeq 550 SY-415-1002</td>
			<td>Illumina</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Shaker Unimax 2010</td>
			<td>Heidolph Instruments</td>
			<td></td>
			<td>for cultivation</td>
		</tr>
		<tr>
			<td>Sodium acetate</td>
			<td>Carl Roth</td>
			<td>127-09-3</td>
			<td>NaCH3COO</td>
		</tr>
		<tr>
			<td>Sodium chloride</td>
			<td>Carl Roth</td>
			<td>7647-14-5</td>
			<td>NaCl</td>
		</tr>
		<tr>
			<td>Sodium dihydrogen phosphate monohydrate</td>
			<td>Carl Roth</td>
			<td>10049-21-5</td>
			<td>NaH2PO4 &#183; H2O</td>
		</tr>
		<tr>
			<td>Sodium fluoride</td>
			<td>Carl Roth</td>
			<td>7681-49-4</td>
			<td>NaF</td>
		</tr>
		<tr>
			<td>Sodium hydrogen carbonate</td>
			<td>Carl Roth</td>
			<td>144-55-8</td>
			<td>NaHCO3</td>
		</tr>
		<tr>
			<td>Sodium molybdate dihydrate</td>
			<td>Serva</td>
			<td>10102-40-6</td>
			<td>Na2MoO4 &#183; 2 H2O</td>
		</tr>
		<tr>
			<td>Sodium nitrate</td>
			<td>Merck</td>
			<td>7631-99-4</td>
			<td>NaNO3</td>
		</tr>
		<tr>
			<td>Sodium sulphate</td>
			<td>Carl Roth</td>
			<td>7757-82-6</td>
			<td>Na2SO4</td>
		</tr>
		<tr>
			<td>Strontium chloride hexahydrate</td>
			<td>Carl Roth</td>
			<td>10025-70-4</td>
			<td>SrCl2 &#183; 6 H2O</td>
		</tr>
		<tr>
			<td>Thiamine hydrochloride</td>
			<td>Merck</td>
			<td>67-03-8</td>
			<td>C12H17ClN4OS &#183; HCl</td>
		</tr>
		<tr>
			<td>TRIS</td>
			<td>Carl Roth</td>
			<td>77-86-1</td>
			<td>C4H11NO3</td>
		</tr>
		<tr>
			<td>Ultrasonic device UP100H with sonotrode MS3</td>
			<td>Hielscher Ultrasound Technology</td>
			<td>UP100H</td>
			<td></td>
		</tr>
		<tr>
			<td>Ultraturrax Silent Crusher M</td>
			<td>Heidolph Instruments</td>
			<td></td>
			<td>homogenizer</td>
		</tr>
		<tr>
			<td>Urea</td>
			<td>Carl Roth</td>
			<td>57-13-6</td>
			<td>CH4N2O</td>
		</tr>
		<tr>
			<td>Vitamin B12</td>
			<td>Sigma</td>
			<td>68-19-9</td>
			<td>C63H88CoN14O14P</td>
		</tr>
		<tr>
			<td>Vitamin solution</td>
			<td></td>
			<td></td>
			<td>0.3 &#181;M thiamin-HCl, 2.1 nM biotin, 0.37 nM cyanocobalamin</td>
		</tr>
		<tr>
			<td>Water Stills, Water treatment</td>
			<td>VEOLIA water technologies</td>
			<td>ELGA_21001</td>
			<td></td>
		</tr>
		<tr>
			<td>Zinc sulphate heptahydrate</td>
			<td>Sigma</td>
			<td>7446-20-0</td>
			<td>ZnSO4 &#183; 7 H2O</td>
		</tr>
		<tr>
			<td>software, URL</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>gatb-minia program for DNA assembly</td>
			<td>https://github.com/GATB/gatb-minia-pipeline</td>
			<td>makes large scaffolds from short DNA reads, Linux based</td>
			<td></td>
		</tr>
		<tr>
			<td>ImageJ</td>
			<td></td>
			<td>software for immage processing (pixel intensities, circle diameter)</td>
			<td></td>
		</tr>
		<tr>
			<td>RAST annotation server</td>
			<td>https://rast.nmpdr.org</td>
			<td>input: genome DNA sequence, detects open reading frames, lists protein sequences and their functions</td>
			<td></td>
		</tr>
		<tr>
			<td>Culture media</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Artificial seawater</td>
			<td colspan="3">0.41 M NaCl , 53 mM MgCl2,28 mM Na2SO4, 10 mM CaCl2 , 9 mM&#160; KCl , 2.4 mM NaHCO3 ,0.84 mM KBr, 0.49 mM H3BO3, 90 &#181;M SrCl2, 72 &#181;M NaF</td>
		</tr>
		<tr>
			<td>f/2 -liquid medium</td>
			<td colspan="3">artificial seawater, 0.1 % (v/v) trace element solution, 0.05 % (v/v) vitamin solution, 0.88 mM NaNO3, 36 &#181;M NaH2PO4&#160;</td>
		</tr>
		<tr>
			<td>f/2+ liquid medium</td>
			<td colspan="3">f/2-medium, with 10 times increased NaNO3 and NaH2PO4 (0.88 mM NaNO3, 36 &#181;M NaH2PO4</td>
		</tr>
		<tr>
			<td>f/2+-agar</td>
			<td colspan="3">3 % (w/v) bacto agar, artificial seawater, 0.1 % (v/v) trace element solution, 0.05 % (v/v) vitamin solution ,8.8 mM NaNO3, 0.36 mM NaH2PO4</td>
		</tr>
		<tr>
			<td>f/2-agar</td>
			<td colspan="3">3 % (w/v) bacto agar, artificial seawater, 0.1 % (v/v) trace element solution, 0.05 % (v/v) vitamin solution ,0.88 mM NaNO3, 36 &#181;M NaH2PO4</td>
		</tr>
		<tr>
			<td>Trace element solution</td>
			<td colspan="3">0.36 mM NaH2PO4, 12 &#181;M Na2EDTA, 39 nM CuSO4, 26 nM Na2MoO4 , 77 nM ZnSO4, 42 nM CoCl2, 0.91 &#181;M MnCl2</td>
		</tr>
		<tr>
			<td>Vitamin solution</td>
			<td colspan="2">0.3 &#181;M thiamin-HCl, 2.1 nM biotin, 0.37 nM cyanocobalamin</td>
			<td></td>
		</tr>
	</tbody>
</table>

natural transformation, protein expression, and cryoconservation of the filamentous cyanobacterium phormidium lacuna

Cyanobacteria are the focus of basic research and biotechnological projects in which solar energy is utilized for biomass production. Phormidium lacuna is a newly isolated filamentous cyanobacterium. This paper describes how new filamentous cyanobacteria can be isolated from marine rockpools. It also describes how DNA can be extracted from filaments and how the genomes can be sequenced. Although transformation is established for many single-celled species, it is less frequently reported for filamentous cyanobacteria. A simplified method for the natural transformation of P. lacuna is described here. P. lacuna is the only member of the order Oscillatoriales for which natural transformation is established. This paper also shows how natural transformation is used to express superfolder green fluorescent protein (sfGFP). An endogenous cpcB promoter induced approximately 5 times stronger expression than cpc560, A2813, or psbA2 promoters from Synechocystis sp. PCC6803. Further, a method for the cryopreservation of P. lacuna and Synechocystis sp. CPP 6803 was established, and methods for assessing motility in a liquid medium and on agar and plastic surfaces are described.

Following the above-mentioned methods, 5 different strains of P. lacuna were isolated from rockpools and sequenced (Figure 1 and Table 1). All cultures were sterile after ~1 year of subculturing except P. lacuna HE10JO. This strain is still contaminated with Marivirga atlantica, a marine bacterium. During subsequent Helgoland excursions, other filamentous cyanobacteria were isolated from rock pools, which are different from P. lacuna and n...

Watch this Scientific Journal Video about Natural Transformation, Protein Expression, and Cryoconservation of the Filamentous Cyanobacterium Phormidium lacuna at JoVE.com

Natural Transformation, Protein Expression, and Cryoconservation of the Filamentous Cyanobacterium Phormidium lacuna

Phormidium lacuna is a filamentous cyanobacterium that was isolated from marine rockpools. This article describes the isolation of filaments from natural sources, DNA extraction, genome sequencing, natural transformation, expression of sfGFP, cryoconservation, and motility methods.

Natural Transformation, Protein Expression, and Cryoconservation of the Filamentous Cyanobacterium Phormidium lacuna

Cyanobacteria are the focus of basic research and biotechnological projects in which solar energy is utilized for biomass production. Phormidium lacuna is ...

This protocol describes how filamentous cyanobacterium that belongs to oscillatoriales can be transformed by natural transformation. It also shows how different kinds of motion can be studied. Natural transformation is the simplest transformation technique, if it works.Only DNA, cells, and growth medium are required. So far, no other oscillatoriales member could be transformed by natural transformation. We hope that our studies stimulate other groups to try other oscillatoria.For transformation, make a good, healthy looking-culture and a good DNA preparation. For motion studies, always use an ultrasound-treated culture. Treatment should be fresh.Demonstrating the procedure will be Nora Weber, a technician from my laboratory. Begin by inoculating 50 milliliters liquid F2 medium into each of the two 250-milliliter flasks with one milliliter of P.lacuna filaments from a running culture. Cultivate in white light under agitation for around five days at 25 degrees Celsius.After five days, homogenize 100 milliliters of P.lacuna cell suspension at 10, 000 RPM for three minutes and measure the optical density at 750 nanometers. Then, centrifuge the cell suspension for 15 minutes at 6, 000 times G.Remove the supernatant and suspend the pellet in 800 microliters of the remaining liquid and additional F2+medium. Take eight F2+Bacto agar plates containing 120 micrograms per milliliter kanamycin and pipette 10 micrograms of DNA into the middle of each agar plate.Immediately pipette 100 microliters of the cell suspension on top of the DNA. Keep the agar plate without a lid on the clean bench to allow the excess liquid to evaporate. Close the plate and cultivate it in white light at 25 degrees Celsius for two days.After two days, distribute the filaments of each agar plate onto several fresh F2+Bacto agar plates containing 120 micrograms per milliliter kanamycin with an inoculation loop. Cultivate the plates in white light at 25 degrees Celsius and check the cultures regularly under a microscope. After 14 to 28 days, identify the dead brownish filaments and search for transformed filaments under the microscope.The transformed filaments look healthy and green and are different from the bulk of filaments. Transfer each single transformed filament into 50-milliliter flasks with 10 milliliters of F2+medium with 250 micrograms per milliliter kanamycin. Cultivate in white light at 25 degrees Celsius on a shaker and observe growth for up to four weeks.Transfer the filaments back to the agar medium containing 250 micrograms per milliliter kanamycin and wait for the filaments to grow. Then, increase the kanamycin concentration again to speed up the segregation. For GFP expression, observes single filaments with a fluorescence microscope at 40X or 63X magnification and capture a bright-field transmission image and a fluorescence image.Cultivate P.lacuna in F2 medium under 50 RPM horizontal agitation in white light for around five days until the estimated optical density at 750 nanometers becomes 0.35. Store the sample at four degrees Celsius. Homogenize the filaments with ultrasound for one minute at maximum power and cycle of one.Measure the optical density at 750 nanometers and transfer eight milliliters of the medium containing P.lacuna into a six-centimeter Petri dish. Wait for a few minutes until the sample reaches room temperature and then cover the Petri dish with cellophane foil. Place a microscope slide on the X-Y table of a standard microscope with a camera.Switch on the microscope light and move a 4X or 10X objective into the path of the light. Then, place the Petri dish on top of the slide. Adjust single filaments or filament bundles by the table's X, Y, and Z movements.Observe the movements of single filaments or bundles and record the movements with a standard microscope camera. Ensure that the objective lens does not touch the liquid. Pipette 0.5 milliliters of a solution containing P.lacuna on the Bacto agar surface of a six-centimeter Petri dish.Allow the liquid to enter the surface. After around 20 minutes, close the Petri dish and observe the movement of the filaments on the surface using a 4X or 10X objective. Capture the time lapse recordings using an ocular camera and a mini-computer system.The filaments must first be focused by eye and then through the ocular camera. Ensure that the time interval between the subsequent images is five seconds to one minute. Program the Linux script of the mini-computer to control the time lapse recording.Prepare LED holders where the five millimeter LEDs are mounted to irradiate an area of 20-millimeters square from below to above. Measure and adjust the LED intensities. Ensure that the whole setting is in a dark room or a closed, dark container.Place eight milliliters of the medium containing P.lacuna into a six-centimeter Petri dish, close the Petri dish with the lid, and place it on an LED holder so that the LED is in the center of the Petri dish. After typically two days, capture an image of the Petri dish with a smartphone camera aimed directly at the position of the light treatment. Use a holder and a white sheet as a background to ensure the same distance and light conditions for every picture.Open the ImageJ software, click on File, Open, and select the file. Then, click on Enter. Select the straight button and press the left mouse button to draw a line from one end of the Petri dish to the opposite end.Ensure that the line passes through the center of the circle of filaments. Click on Analyze and Measure to see the length of the Petri dish. Then, click on Analyze and Plot Profile in the ImageJ menu.Estimate an average value for the pixel intensity outside the circle and another average value for the pixel intensity inside the circle. Point the mouse on the Y position between these values to estimate the X values of both sides of the circle. Note both values and calculate the difference.Then select the straight button and draw a line at the mid-maximum value of the pixel intensity. Finally, click on Analyze and then Measure to get the length of the inner cell circle. Integration and segregation of insert after the transformation of P.lacuna with PAK1 is shown here.A PCR test with outer primers around one week after the transformation typically has two bands on the electrophoresis gel, one with the size of the wild-type band, and one slower migrating band that indicates the insertion of the resistance cassette. Here, lanes 1 to 4 represent PCR products of filaments after seven days, 11 days, 14 days, and 17 days of the isolation of a resistant filament, and lane 5 represents PCR product of wild-type. In the seven-day sample, the insert is present in a small fraction of the chromosomes.This fraction increases until 17 days, where no wild-type band is visible;that is, the segregation is complete. This image represents the vector pMH1 for sfGHP expression under the control of endogenous phycocyanin beta promoter. P.lacuna homologous sequence, pUC19 vector backbone, and insert with sfGFP and kanamycin resistance are shown here.In pMH1, the sfGHP gene is placed three prime of the phycocyanin beta gene;therefore, it is driven by the endogenous cpc beta promoter. Fluorescence images of P.lacuna wild-type filaments and after transformation with PAK1, PAK2, PAK3, and pMH1 are shown here. The expression of sfGFP is driven by the cpc 560 promoter, the a2813 promoter, the psbA2S promoter, or the endogenous cpc beta promoter.The merged images presented here show the motility of Phormidium lacuna. The movement on the agar surface is shown here. The time interval was one minute.The movement in the liquid medium is presented here. The time interval was 10 seconds. Natural transformation is a simple method.Just mix plasmid DNA with a resistance cassette in homologous sequences with the cells and let the cells grow on a medium with antibiotics. Genes can be inactivated and proteins can be overexpressed. This is important for any basic research and for biotechnical studies.In single-cell cyanobacteria where natural transformation is also established, molecular studies on photosynthesis or photoreceptors, et cetera, were addressed.

Research

JoVE Journal

Biology

The Preparation of Primary Hematopoietic Cell Cultures From Murine Bone Marrow for Electroporation

It is becoming increasingly apparent that electroporation is the most effective way to introduce plasmid DNA or siRNA into primary cells. The Gene Pulser ...

Staining of Proteins in Gels with Coomassie G-250 without Organic Solvent and Acetic Acid

In classical protein staining protocols using Coomassie Brilliant Blue (CBB), solutions with high contents of toxic and flammable organic solvents ...

Using the Gene Pulser MXcell Electroporation System to Transfect Primary Cells with High Efficiency

Using the GELFREE 8100 Fractionation System for Molecular Weight-Based Fractionation with Liquid Phase Recovery

The GELFREE 8100 Fractionation System is a novel protein fractionation system designed to maximize protein recovery during molecular weight based ...

Floral-dip Transformation of Arabidopsis thaliana to Examine pTSO2::&beta;-glucuronidase Reporter Gene Expression

Floral-dip Transformation of Arabidopsis thaliana to Examine pTSO2::&#946;-glucuronidase Reporter Gene Expression

The ability to introduce foreign genes into an organism is the foundation for modern biology and biotechnology. In the model flowering plant Arabidopsis ...

Expression, Detergent Solubilization, and Purification of a Membrane Transporter, the MexB Multidrug Resistance Protein

Multidrug resistance (MDR), the ability of a cancer cell or pathogen to be resistant to a wide range of structurally and functionally unrelated ...

In vitro Reconstitution of the Active T. castaneum Telomerase

In vitro Reconstitution of the Active T. castaneum Telomerase

Efforts to isolate the catalytic subunit of telomerase, TERT, in sufficient quantities for structural studies, have been met with limited success for more ...

Expression and Purification of the Cystic Fibrosis Transmembrane Conductance Regulator Protein in Saccharomyces cerevisiae

Expression and Purification of the Cystic Fibrosis Transmembrane Conductance Regulator Protein in Saccharomyces cerevisiae

The  cystic fibrosis transmembrane conductance regulator (CFTR) is a chloride  channel, that when mutated, can give rise to cystic fibrosis in  ...

Analysis of Global RNA Synthesis at the Single Cell Level following Hypoxia

Hypoxia or lowering of the oxygen availability is involved in many physiological and pathological processes. At the molecular level, cells initiate a ...

siRNA Screening to Identify Ubiquitin and Ubiquitin-like System Regulators of Biological Pathways in Cultured Mammalian Cells

Post-translational modification of proteins with ubiquitin and ubiquitin-like molecules (UBLs) is emerging as a dynamic cellular signaling network that ...