This work was funded by the Ministry of Education ERC CZ grant LL1205, the Grant Agency of Czech Republic grant 18-17529S, and by ERDF/ESF project Centre for research of pathogenicity and virulence of parasites (No. CZ.02.1.01/0.0/0.0/16_019/0000759).

1. Buffers and Solutions
<ol>
	<li>Prepare the solutions listed below. Degas all buffers for liquid chromatography. Add ADP, benzamidine, and protease inhibitors just before use.
	<ol>
		<li>Prepare buffer A: 50 mM Tris buffer with hydrochloric acid (Tris-HCl) pH 8.0, 0.25 M sucrose, 5 mM benzamidine, 5 mM aminocaproic acid (ACA), and protease inhibitors (10 &#181;M amastatin, 50 &#181;M bestatin, 50 &#181;M pepstatin, 50 &#181;M leupeptin, and 50 &#181;M diprotin A).</li>
		<li>Prepare buffer B: 50 mM Tris-HCl pH 8.0,...

<ol>
	<li>Walker, J. E., Wikstr&#246;m, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structure,+mechanism+and+regulation+of+ATP+synthases.">Structure, mechanism and regulation of ATP synthases.</a> Mechanisms of Primary Energy Transduction in Biology. , 338-373 (2017).</li><li>Pullman, M. E., Penefsky, H. S., Datta, A., Racker, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Partial+resolution+of+the+enzymes+catalyzing+oxidative+phosphorylation.+I.+Purification+and+properties+of+soluble+dinitrophenol-stimulated+adenosine+triphosphatase.">Partial resolution of the enzymes catalyzing oxidative phosphorylation. I. Purification and properties of soluble dinitrophenol-stimulated adenosine triphosphatase.</a> The Journal of Biological Chemistry. 235, 3322-3329 (1960).</li><li>Schatz, G., Penefsky, H. S., Racker, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Partial+resolution+of+the+enzymes+catalyzing+oxidative+phosphorylation.">Partial resolution of the enzymes catalyzing oxidative phosphorylation.</a> XIV. The Journal of Biological Chemistry. 242 (10), 2552-2560 (1967).</li><li>Racker, E., Horstman, L. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Partial+resolution+of+the+enzymes+catalyzing+oxidative+phosphorylation.+13.+Structure+and+function+of+submitochondrial+particles+completely+resolved+with+respect+to+coupling+factor.">Partial resolution of the enzymes catalyzing oxidative phosphorylation. 13. Structure and function of submitochondrial particles completely resolved with respect to coupling factor.</a> The Journal of Biological Chemistry. 242 (10), 2547-2551 (1967).</li><li>Senior, A. E., Brooks, 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=Studies+on+the+mitochondrial+oligomycin-insensitive+ATPase.+I.+An+improved+method+of+purification+and+the+behavior+of+the+enzyme+in+solutions+of+various+depolymerizing+agents.">Studies on the mitochondrial oligomycin-insensitive ATPase. I. An improved method of purification and the behavior of the enzyme in solutions of various depolymerizing agents.</a> Archives of Biochemistry and Biophysics. 140 (1), 257-266 (1970).</li><li>Tzagoloff, A., Meagher, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assembly+of+the+mitochondrial+membrane+system.+V.+Properties+of+a+dispersed+preparation+of+the+rutamycin-sensitive+adenosine+triphosphatase+of+yeast+mitochondria.">Assembly of the mitochondrial membrane system. V. Properties of a dispersed preparation of the rutamycin-sensitive adenosine triphosphatase of yeast mitochondria.</a> The Journal of Biological Chemistry. 246 (23), 7328-7336 (1971).</li><li>Beechey, R. B., Hubbard, S. A., Linnett, P. E., Mitchell, A. D., Munn, E. 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+simple+and+rapid+method+for+the+preparation+of+adenosine+triphosphatase+from+submitochondrial+particles.">A simple and rapid method for the preparation of adenosine triphosphatase from submitochondrial particles.</a> Biochemical Journal. 148 (3), 533-537 (1975).</li><li>Tyler, D. D., Webb, P. R. <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+the+adenosine+triphosphatase+released+from+the+liver+mitochondrial+membrane+by+chloroform.">Purification and properties of the adenosine triphosphatase released from the liver mitochondrial membrane by chloroform.</a> Biochemical Journal. 178 (2), 289-297 (1979).</li><li>Hack, E., Leaver, C. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+alpha-subunit+of+the+maize+F1-ATPase+is+synthesised+in+the+mitochondrion.">The alpha-subunit of the maize F1-ATPase is synthesised in the mitochondrion.</a> The EMBO Journal. 2 (10), 1783-1789 (1983).</li><li>Dunn, P. P., Slabas, A. R., Moore, A. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Purification+of+F1-ATPase+from+cuckoo-pint+(Arum+maculatum)+mitochondria.+A+comparison+of+subunit+composition+with+that+of+rat+liver+F1-ATPase.">Purification of F1-ATPase from cuckoo-pint (Arum maculatum) mitochondria. A comparison of subunit composition with that of rat liver F1-ATPase.</a> Biochemical Journal. 225 (3), 821-824 (1985).</li><li>Satre, M., Bof, M., Vignais, P. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Interaction+of+Escherichia+coli+adenosine+triphosphatase+with+aurovertin+and+citreoviridin:+inhibition+and+fluorescence+studies.">Interaction of Escherichia coli adenosine triphosphatase with aurovertin and citreoviridin: inhibition and fluorescence studies.</a> Journal of Bacteriology. 142 (3), 768-776 (1980).</li><li>Abrahams, J. P., Leslie, A. G., Lutter, R., Walker, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structure+at+2.8+&#197;+resolution+of+F1ATPase+from+bovine+heart+mitochondria.">Structure at 2.8 &#197; resolution of F1ATPase from bovine heart mitochondria.</a> Nature. 370 (6491), 621-628 (1994).</li><li>Lutter, R., 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=Crystallization+of+F1-ATPase+from+bovine+heart+mitochondria.">Crystallization of F1-ATPase from bovine heart mitochondria.</a> Journal of Molecular Biology. 229 (3), 787-790 (1993).</li><li>Kabaleeswaran, V., Puri, N., Walker, J. E., Leslie, A. G., Mueller, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Novel+features+of+the+rotary+catalytic+mechanism+revealed+in+the+structure+of+yeast+F1-ATPase.">Novel features of the rotary catalytic mechanism revealed in the structure of yeast F1-ATPase.</a> The EMBO Journal. 25 (22), 5433-5442 (2006).</li><li>Shirakihara, Y., 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=Structure+of+a+thermophilic+F1-ATPase+inhibited+by+an+epsilon-subunit:+deeper+insight+into+the+epsilon-inhibition+mechanism.">Structure of a thermophilic F1-ATPase inhibited by an epsilon-subunit: deeper insight into the epsilon-inhibition mechanism.</a> The FEBS Journal. 282 (15), 2895-2913 (2015).</li><li>Stocker, A., Keis, S., Cook, G. M., Dimroth, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Purification,+crystallization,+and+properties+of+F1-ATPase+complexes+from+the+thermoalkaliphilic+Bacillus+sp.+strain+TA2.A1.">Purification, crystallization, and properties of F1-ATPase complexes from the thermoalkaliphilic Bacillus sp. strain TA2.A1.</a> Journal of Structural Biology. 152 (2), 140-145 (2005).</li><li>Ferguson, S. A., Cook, G. M., Montgomery, M. G., Leslie, A. G., Walker, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regulation+of+the+thermoalkaliphilic+F1-ATPase+from+Caldalkalibacillus+thermarum.">Regulation of the thermoalkaliphilic F1-ATPase from Caldalkalibacillus thermarum.</a> Proceedings of the National Academy of Sciences of the United States of America. 113 (39), 10860-10865 (2016).</li><li>Cataldi de Flombaum, M. A., Frasch, A. C. C., Stoppani, A. O. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adenosine+triphosphatase+from+Trypanosoma+cruzi:+purification+and+properties.">Adenosine triphosphatase from Trypanosoma cruzi: purification and properties.</a> Comparative Biochemistry and Physiology Part B: Comparative Biochemistry. 65 (1), 103-109 (1980).</li><li>Williams, N., Frank, P. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+mitochondrial+ATP+synthase+of+Trypanosoma+brucei:+isolation+and+characterization+of+the+intact+F1+moiety.">The mitochondrial ATP synthase of Trypanosoma brucei: isolation and characterization of the intact F1 moiety.</a> Molecular and Biochemical Parasitology. 43 (1), 125-132 (1990).</li><li>Higa, A. I., Cazzulo, J. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mg2+-activated+adenosine+triphosphatase+from+Crithidia+fasciculata:+purification+and+inhibition+by+suramin+and+efrapeptin.">Mg2+-activated adenosine triphosphatase from Crithidia fasciculata: purification and inhibition by suramin and efrapeptin.</a> Molecular and Biochemical Parasitology. 3 (6), 357-367 (1981).</li><li>Walker, J. E., 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=Primary+structure+and+subunit+stoichiometry+of+F1-ATPase+from+bovine+mitochondria.">Primary structure and subunit stoichiometry of F1-ATPase from bovine mitochondria.</a> Journal of Molecular Biology. 184 (4), 677-701 (1985).</li><li>Mueller, D. M., 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=Ni-chelate-affinity+purification+and+crystallization+of+the+yeast+mitochondrial+F1-ATPase.">Ni-chelate-affinity purification and crystallization of the yeast mitochondrial F1-ATPase.</a> Protein Expression and Purification. 37 (2), 479-485 (2004).</li><li>Gahura, O., 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+F1-ATPase+from+Trypanosoma+brucei+is+elaborated+by+three+copies+of+an+additional+p18-subunit.">The F1-ATPase from Trypanosoma brucei is elaborated by three copies of an additional p18-subunit.</a> The FEBS Journal. 285 (3), 614-628 (2018).</li><li>Montgomery, M. G., Gahura, O., Leslie, A. G. W., Zikova, A., Walker, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=ATP+synthase+from+Trypanosoma+brucei+has+an+elaborated+canonical+F1-domain+and+conventional+catalytic+sites.">ATP synthase from Trypanosoma brucei has an elaborated canonical F1-domain and conventional catalytic sites.</a> Proceedings of the National Academy of Sciences of the United States of America. 115 (9), 2102-2107 (2018).</li><li>Schneider, A., Charriere, F., Pusnik, M., Horn, E. K. <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+mitochondria+from+procyclic+Trypanosoma+brucei.">Isolation of mitochondria from procyclic Trypanosoma brucei.</a> Methods in Molecular Biology. 372, 67-80 (2007).</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>Wirtz, E., Leal, S., Ochatt, C., Cross, G. 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+tightly+regulated+inducible+expression+system+for+conditional+gene+knock-outs+and+dominant-negative+genetics+in+Trypanosoma+brucei.">A tightly regulated inducible expression system for conditional gene knock-outs and dominant-negative genetics in Trypanosoma brucei.</a> Molecular and Biochemical Parasitology. 99 (1), 89-101 (1999).</li><li>Speijer, D., 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+the+respiratory+chain+from+cultured+Crithidia+fasciculata.">Characterization of the respiratory chain from cultured Crithidia fasciculata.</a> Molecular and Biochemical Parasitology. 85 (2), 171-186 (1997).</li><li>Nelson, R. E., Aphasizheva, I., Falick, A. M., Nebohacova, M., Simpson, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+I-complex+in+Leishmania+tarentolae+is+an+uniquely-structured+F1-ATPase.">The I-complex in Leishmania tarentolae is an uniquely-structured F1-ATPase.</a> Molecular and Biochemical Parasitology. 135 (2), 221-224 (2004).</li><li>Carbajo, R. 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=How+the+N-terminal+domain+of+the+OSCP+subunit+of+bovine+F1Fo-ATP+synthase+interacts+with+the+N-terminal+region+of+an+alpha+subunit.">How the N-terminal domain of the OSCP subunit of bovine F1Fo-ATP synthase interacts with the N-terminal region of an alpha subunit.</a> Journal of Molecular Biology. 368 (2), 310-318 (2007).</li><li>Bowler, M. W., Montgomery, M. G., Leslie, A. G., Walker, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ground+state+structure+of+F1-ATPase+from+bovine+heart+mitochondria+at+1.9+&#197;+resolution.">Ground state structure of F1-ATPase from bovine heart mitochondria at 1.9 &#197; resolution.</a> The Journal of Biological Chemistry. 282 (19), 14238-14242 (2007).</li></ol>

The authors have nothing to disclose.

The protocol for F1-ATPase purification from T. brucei was developed based on previously published methods for the isolation of F1-ATPase complexes from other species13,14. The method does not require any genetic modification (e.g., tagging) and yields a fully active complex with all subunits present. The crucial step is the chloroform-facilitated release of the F1-ATPase from the membrane-attached part of the en...

The F-type ATP synthases are membrane-bound rotating multiprotein complexes that couple proton translocation across energy-transducing membranes of bacteria, mitochondria, and chloroplasts with the formation of ATP. Molecular details of the rotational mechanism of ATP synthesis are known mainly because of structural studies of purified bacterial and mitochondrial ATP synthases and their subcomplexes1. F-type ATP synthase is organized into membrane-intrinsic and membrane-extrinsic moieties. The membrane-extrinsic part, known as F1-ATPase, contains three catalytic sites, where the phosphorylation of adenosine diphosphate (ADP) to ATP or the reverse reaction occurs. F1-ATPase can be released experimentally from the membrane-intrinsic moiety while retaining its ability to hydrolyze, but not synthesize, ATP. The membrane-bound sector, called Fo, mediates protein translocation, which drives the rotation of the central part of the enzyme. The F1 and Fo sectors are connected by the&#160;central and peripheral stalks.
The first attempts to purify the F1-ATPase from budding yeast and bovine heart mitochondria date back to the 1960s. These protocols used extracted mitochondria, which were disrupted by sonication, fractionated by ammonium or protamine sulfate precipitation, followed by optional chromatography step(s) and heat treatment2,3,4,5,6. The purification was greatly improved and simplified by the use of chloroform, which readily releases the F1-ATPase from the mitochondrial membrane fragments7. The chloroform extraction was then used to extract F1-ATPases from various animal, plant, and bacterial sources (e.g., rat liver8, corn9, Arum maculatum10, and Escherichia coli11). Further purification of the chloroform-released F1-ATPase by affinity or size-exclusion chromatography (SEC) yielded a highly pure protein complex, which was suitable for high-resolution structure determination by X-ray crystallography, as documented by the structures of F1-ATPase from bovine heart12,13 and Saccharomyces cerevisiae14. F1-ATPase structures were also determined from organisms that are difficult to cultivate and, thus, the amount of the initial biological material was limited. In this case, the F1-ATPase subunits were artificially expressed and assembled into the complex in E. coli, and the whole heterologous enzyme was purified by affinity chromatography via a tagged subunit. Such approach led to the determination of F1-ATPase structures from two thermophilic bacterial species, Geobacillus stearothermophilus15 and Caldalkalibacillus thermarum16,17. However, this methodology is rather unsuitable for eukaryotic F1-ATPases since it relies on the prokaryotic protheosynthetic apparatus, posttranslational processing, and complex assembly.
The chloroform-based extraction was previously used to isolate F1-ATPases from unicellular digenetic parasites Trypanosoma cruzi18 and T. brucei19, important mammalian pathogens causing American and African trypanosomiases, respectively, and from monogenic insect parasite Crithidia fasciculata20. These purifications led only to a simple description of the F1-ATPases, since no downstream applications were used to fully characterize the composition, structure, and enzymatic properties of the complex. This article describes an optimized method for F1-ATPase purification from the cultured insect life cycle stage of T. brucei. The method is developed based on the established protocols for isolation of bovine and yeast F1-ATPases21,22. The procedure yields highly pure and homogeneous enzyme suitable for in vitro enzymatic and inhibitory assays, detailed proteomic characterization by mass spectrometry23, and structure determination24. The purification protocol and the knowledge of the F1-ATPase structure at the atomic level opens a possibility to design screens to identify small-molecule inhibitors, and aid in the development of new drugs against African trypanosomiases. Moreover, the protocol can be adapted to purify F1-ATPase from other organisms.

<table>
	<tbody>
		<tr>
			<td>Chemicals</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Adenosin Diphosphate Disodium Salt (ADP)</td>
			<td>Applichem</td>
			<td>A0948</td>
			<td></td>
		</tr>
		<tr>
			<td>Amastatin Hydrochloride</td>
			<td>Glantham Life Sciences</td>
			<td>GA1330</td>
			<td></td>
		</tr>
		<tr>
			<td>Aminocaproic Acid</td>
			<td>Applichem</td>
			<td>A2266</td>
			<td></td>
		</tr>
		<tr>
			<td>BCA Protein Assay Kit</td>
			<td>ThermoFischer Scientific/Pierce</td>
			<td>23225</td>
			<td></td>
		</tr>
		<tr>
			<td>Benzamidine Hydrochloride</td>
			<td>Calbiochem</td>
			<td>199001</td>
			<td></td>
		</tr>
		<tr>
			<td>Bestatin Hydrochloride</td>
			<td>Sigma Aldrich/Merck</td>
			<td>B8385</td>
			<td></td>
		</tr>
		<tr>
			<td>Chloroform</td>
			<td>Any supplier</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>cOmplete Tablets, Mini EDTA-free</td>
			<td>Roche</td>
			<td>4693159001</td>
			<td>Protease inhibitor cocktail tablets</td>
		</tr>
		<tr>
			<td>Ethylenediaminetetraacetic Acid (EDTA)</td>
			<td>Any supplier</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Hydrochloric Acid</td>
			<td>Any supplier</td>
			<td></td>
			<td>For pH adjustment</td>
		</tr>
		<tr>
			<td>Ile-Pro-Ile</td>
			<td>Sigma Aldrich/Merck</td>
			<td>I9759</td>
			<td>Alias Diprotin A</td>
		</tr>
		<tr>
			<td>Leupeptin</td>
			<td>Sigma Aldrich/Merck</td>
			<td>L2884</td>
			<td></td>
		</tr>
		<tr>
			<td>Magnesium Sulfate Heptahydrate</td>
			<td>Any supplier</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Pepstatin A</td>
			<td>Sigma Aldrich/Merck</td>
			<td>P5318</td>
			<td></td>
		</tr>
		<tr>
			<td>Protein Electrophoresis System</td>
			<td>Any supplier</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium Chloride</td>
			<td>Any supplier</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Sucrose</td>
			<td>Any supplier</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Tris</td>
			<td>Any supplier</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Consumables</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Centrifuge Tubes for SW60Ti, Polyallomer</td>
			<td>Beckman Coulture</td>
			<td>328874</td>
			<td></td>
		</tr>
		<tr>
			<td>DounceTissues Homogenizer 2 mL</td>
			<td>Any supplier</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Glass Vacuum Filtration Device</td>
			<td>Sartorius</td>
			<td>516-7017</td>
			<td>Degasing solutions for liquid chromatography</td>
		</tr>
		<tr>
			<td>HiTrap Q HP, 5 mL</td>
			<td>GE Healthcare Life Sciences</td>
			<td>17115401</td>
			<td>Anion exchange chromatography column</td>
		</tr>
		<tr>
			<td>Regenaretad Cellulose Membrane Filters, pore size 0.45 &#956;m, diameter 47 mm</td>
			<td>Sartorius</td>
			<td>18406--47------N</td>
			<td>Degasing solutions for liquid chromatography</td>
		</tr>
		<tr>
			<td>Superdex 200 Increase 10/300 GL</td>
			<td>GE Healthcare Life Sciences</td>
			<td>29091596</td>
			<td>Size-exclusion chromatography column</td>
		</tr>
		<tr>
			<td>Vivaspin 6 MWCO 100 kDa PES</td>
			<td>Sartorius</td>
			<td>VS0641</td>
			<td></td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Equipment</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>AKTA Pure 25</td>
			<td>GE Healthcare Life Sciences</td>
			<td>29018224</td>
			<td>Or similar FPLC system</td>
		</tr>
		<tr>
			<td>Spectrophotometer Shimadzu UV-1601</td>
			<td>Shimadzu</td>
			<td></td>
			<td>Or similar spectrophotometer with kinetic assay mode</td>
		</tr>
		<tr>
			<td>Ultracentrifuge Beckman Optima with SW60Ti Rotor</td>
			<td>Beckman Coulture</td>
			<td></td>
			<td>Or similar ultracentrifuge and rotor</td>
		</tr>
		<tr>
			<td>Ultrasonic Homogenizer with Thin Probe, Model 3000</td>
			<td>BioLogics</td>
			<td>0-127-0001</td>
			<td>Or similar ultrasonic homogenizer</td>
		</tr>
	</tbody>
</table>

isolation of f1-atpase from the parasitic protist trypanosoma brucei

F1-ATPase is a membrane-extrinsic catalytic subcomplex of F-type ATP synthase, an enzyme that uses the proton motive force across biological membranes to produce adenosine triphosphate (ATP). The isolation of the intact F1-ATPase from its native source is an essential prerequisite to characterize the enzyme&#39;s protein composition, kinetic parameters, and sensitivity to inhibitors. A highly pure and homogeneous F1-ATPase can be used for structural studies, which provide insight into molecular mechanisms of ATP synthesis and hydrolysis. This article describes a procedure for the purification of the F1-ATPase from Trypanosoma brucei, the causative agent of African trypanosomiases. The F1-ATPase is isolated from mitochondrial vesicles, which are obtained by hypotonic lysis from in vitro cultured trypanosomes. The vesicles are mechanically fragmented by sonication and the F1-ATPase is released from the inner mitochondrial membrane by the chloroform extraction. The enzymatic complex is further purified by consecutive anion exchange and size-exclusion chromatography. Sensitive mass spectrometry techniques showed that the purified complex is devoid of virtually any protein contaminants and, therefore, represents suitable material for structure determination by X-ray crystallography or cryo-electron microscopy. The isolated F1-ATPase exhibits ATP hydrolytic activity, which can be inhibited fully by sodium azide, a potent inhibitor of F-type ATP synthases. The purified complex remains stable and active for at least three days at room temperature. Precipitation by ammonium sulfate is used for long-term storage. Similar procedures have been used for the purification of F1-ATPases from mammalian and plant tissues, yeasts, or bacteria. Thus, the presented protocol can serve as a guideline for the F1-ATPase isolation from other organisms.

A typical purification (Figure 1) starts with mitochondrial vesicles (mitoplasts) isolated on the Percoll gradient from hypotonically lysed 1 x 1011 to 2 x 1011 procyclic T. brucei cells25 cultured in standard glucose-rich SDM-79 medium27. The mitoplasts are fragmented by sonication, spun, and the matrix-containing supernatant is discarded. Mitochondrial membranes are treated with ...

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Isolation of F1-ATPase from the Parasitic Protist Trypanosoma brucei

This protocol describes the purification of F1-ATPase from the cultured insect stage of Trypanosoma brucei. The procedure yields a highly pure, homogeneous, and active complex suitable for structural and enzymatic studies.

Isolation of F1-ATPase from the Parasitic Protist Trypanosoma brucei

F1-ATPase is a membrane-extrinsic catalytic subcomplex of F-type ATP synthase, an enzyme that uses the proton motive force across biological membranes to ...

The purification of F1-ATPase is based on a classical biochemical methods which proved to be crucial for our understanding of the mechanism of ATP production by other ATP synthases. The main advantage of this technique is that it produces a highly pure enzyme suitable for structure determination by X-ray crystallography or cryo-electron microscopy. Although this protocol is optimized for the isolation of F1-ATPase from trypanosomes, it can be adapted to other sources, such as tissue or culture cells, and to various pathogenic protists.This technique may lead to the identification of new drugs to treat severe human diseases. For example, Mycobacterium tuberculosis F-ATPase is an authenticated drug target for the treatment of tuberculosis. To begin the protocol, thaw and gently resuspend mitochondrial vesicles, also known as mitoplasts, previously isolated by hypotonic lysis from one times 10 to the 11 to two times 10 to the 11 cells of procyclic Trypanosoma brucei in five milliliters of ice-cold Buffer A.Keep the sample chilled.Next, determine the protein concentration in the suspension by the bicinchoninic acid, or BCA, protein assay according to the manufacturer's instructions. Perform a BSA dilution series in ultra pure water to construct the standard curve. Dilute a small amount of the sample 20 to 100 times with ultra pure water to fit into the range of the BSA standards.After calculating the total protein amount in the sample, bring the protein concentration to 16 milligrams per milliliter by diluting it with additional Buffer A.Then fragment the mitoplasts into inverted vesicles and membrane pieces by sonication seven times for 15 seconds each, with a total energy of 70 to 100 joules per impulse with a microtip with a diameter of 3.9 millimeters. While fragmenting, incubate the sample on ice for 30 seconds between impulses. After the sonication, the suspension might appear slightly darker.Sediment the membrane fragments by ultracentrifugation at 54, 000 g for 16 hours or at 98, 000 g for five hours at four degrees Celsius. Decant the supernatant and proceed with the chloroform extraction. Calculate the volume of Buffer B based on the total amount of Buffer A used.Transfer the frozen sediment from the centrifuge tube into the homogenizer. Resuspend the pellet of mitochondrial membranes in Buffer B with the aid of a small Dounce homogenizer. Transfer the suspension to a 50 milliliter conical tube.Remove the sample from ice, and keep the sample and all the solutions at room temperature for the remaining steps. Then add chloroform saturated with two molar tris adjusted with HCl to pH 8.5, one to one. Close the cap tightly, and shake the sample vigorously for exactly 20 seconds.Immediately centrifuge the mixture at 8, 400 g for five minutes at room temperature. Next, transfer the upper, cloudy aqueous phase to 1.6 milliliter microtubes. Add protease inhibitors to the sample to replace the inhibitors removed by the chloroform treatment.Centrifuge the samples at 13, 000 g for 30 minutes at room temperature. After the spin, transfer the supernatant to fresh microtubes, and repeat the centrifugation to remove any remaining insoluble material. Equilibrate the five milliliter anion exchange Q column attached to a fast protein liquid chromatography system with 50 milliliters of Q column buffer at a flow rate of five milliliters per minute until the absorbance at 280 nanometers and the conductivity stabilize.Load the supernatant on the equilibrated column at a flow rate of one milliliter per minute. Wait until the absorbance at 280 nanometers stabilizes at the background. Apply a 25 milliliter linear gradient of the Q column elution buffer from 0%to 100%at a flow rate of 0.5 milliliters per minute and collect one milliliter fractions.Assay 10 microliters of each individual fraction corresponding to the major elution peak for ATP hydrolytic activity per on milliliter of reaction mixture by the Pullman ATPase assay at pH 8.0. Pool the fractions that exhibit ATPase activity. Concentrate the pooled sample by membrane ultrafiltration using a spin column with a 100, 000 molecular weight cutoff PES filter to 200 to 500 microliters.Then proceed to size exclusion chromatography. Equilibrate the Superose 6 Increase column attached to a liquid chromatography system with at least 48 milliliters of SEC buffer at a flow rate of 0.5 milliliters per minute. Apply the sample to the column.Run the chromatography at a flow rate of 0.25 milliliters per minute, while collecting 0.25 milliliter fractions. Next, run 10 microliters of the fractions that correspond to the peaks of the UV 280 nanometer absorbance trace on SDS-PAGE. Then stain the samples with Coomassie Blue.Assay the fractions corresponding to the first major peak containing the F1 peak for the ATP hydrolytic activity and azide sensitivity by the Pullman ATPase assay. Then perform a BCA assay to determine the protein concentration. Finally, keep the purified F1-ATPase at room temperature, and use it within three days after purification for downstream applications.This elution profile of an anion exchange chromatography displays the UV absorbance at 280 nanometers and concentration of sodium chloride in the elution buffer. The selected fractions were separated on the SDS-PAGE gel and stained with Coomassie Blue dye. The fractions that correspond to the major elution peak from anion exchange chromatography and contain the F1-ATPase were pooled, concentrated, and used as the input for size-exclusion chromatography.The major contaminant is dihydrolipoyl dehydrogenase, which elutes from the size-exclusion chromatography column as a discrete peak. The F1-ATPase elutes in the first dominant, largely symmetric peak. The Coomassie Blue staining of a typical band pattern after the separation of the purified F1-ATPase via SDS-PAGE shows sporadic weak bands visible above the beta subunit, which represent subcomplexes of the alpha three beta three headpiece, dimers and oligomers of the alpha and beta subunits, and are devoid of any contaminants detectable by mass spectrometry.While performing the chloroform extraction, the critical step of the protocol, it is essential to shake the sample vigorously and proceed to the centrifugal separation of the organic and aqueous phases immediately. Following this procedure, the isolated F1-ATPase can be characterized in detail by mass spectrometry. Further, it can be used in activity assays or for structural studies, either on its own or in the presence of various inhibitors or substrate analogs.

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7.1K visualizações.  Czech Academy of Science, Institute of Parasitology. A purificação do F1-ATPase é baseada em métodos bioquímicos clássicos que se mostraram cruciais para nossa compreensão do mecanismo de produção de ATP por outras sínqueses atp. A principal vantagem desta técnica é que ela produz uma enzima altamente pura adequada para a determinação da estrutura por cristalografia de raios-X ou microscopia crio-elétron. Embora este protocolo seja otimizado para o isolamento do F1-ATPase a partir de tripanossomos, ele pode ser adaptado a outras ...