Optimizing the Inhibition of a Uniquely Composed Trypanosoma brucei F1-ATPase

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60077344%3A_____%2F14%3A00488324" target="_blank" >RIV/60077344:_____/14:00488324 - isvavai.cz</a>

Výsledek na webu

<a href="http://www.parazitologie.cz/protozoologie/Protodny2014/JPD_sbornik_2014.pdf" target="_blank" >http://www.parazitologie.cz/protozoologie/Protodny2014/JPD_sbornik_2014.pdf</a>

DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Optimizing the Inhibition of a Uniquely Composed Trypanosoma brucei F1-ATPase

Popis výsledku v původním jazyce

The transition of the parasitic Trypanosoma brucei between its invertebrate and vertebrate hosts is associated with substantial bioenergetic pathway changes. While substrate and oxidative phosphorylation (OXPHOS) provide the main source of ATP in the procyclic stage (PS), increased glycolysis of abundant glucose in the bloodstream form (BS) compensates for the absence of OXPHOS - requiring the F1Fo-ATPase to maintain the mitochondrial membrane potential at the expense of ATP. A widespread natural protein inhibitor of F1Fo-ATPase activity (TbIF1) is expressed in PS, while its ectopic expression is lethal in BS. To characterize TbIF1 inhibition, we isolated the F1-ATPase from PS by two-step chromatography. Besides the conserved eukaryotic components (3 3), the complex contains an additional trypanosomatid-specific protein, p18. The previously reported subunit cleavage was confirmed and modeled to a region presumed to form a loop between the crown and NTP-binding domains, a unique feature of F1-ATPase in Kinetoplastids. Furthermore, several recombinant TbIF1 mutants were characterized to determine their dissociation constants and oligomerization properties. While the C-terminal deletion of TbIF1 prevents homodimerization, it does not disrupt the pH sensitivity as it does in bovine IF1. Importantly, TbIF1 cannot inhibit bovine F1-ATPase and vice versa, strengthening the differences between the parasite and mammals. The established purification of a uniquely composed F1-ATPase is suitable for structure resolution by X-ray crystallography. Given the non-conventional function of F1-ATPase in BS and the F1-TbIF1 binding data, we propose that the structure could be exploited to design specific inhibitors for potential use in therapeutics.n

Název v anglickém jazyce

Optimizing the Inhibition of a Uniquely Composed Trypanosoma brucei F1-ATPase

Popis výsledku anglicky

The transition of the parasitic Trypanosoma brucei between its invertebrate and vertebrate hosts is associated with substantial bioenergetic pathway changes. While substrate and oxidative phosphorylation (OXPHOS) provide the main source of ATP in the procyclic stage (PS), increased glycolysis of abundant glucose in the bloodstream form (BS) compensates for the absence of OXPHOS - requiring the F1Fo-ATPase to maintain the mitochondrial membrane potential at the expense of ATP. A widespread natural protein inhibitor of F1Fo-ATPase activity (TbIF1) is expressed in PS, while its ectopic expression is lethal in BS. To characterize TbIF1 inhibition, we isolated the F1-ATPase from PS by two-step chromatography. Besides the conserved eukaryotic components (3 3), the complex contains an additional trypanosomatid-specific protein, p18. The previously reported subunit cleavage was confirmed and modeled to a region presumed to form a loop between the crown and NTP-binding domains, a unique feature of F1-ATPase in Kinetoplastids. Furthermore, several recombinant TbIF1 mutants were characterized to determine their dissociation constants and oligomerization properties. While the C-terminal deletion of TbIF1 prevents homodimerization, it does not disrupt the pH sensitivity as it does in bovine IF1. Importantly, TbIF1 cannot inhibit bovine F1-ATPase and vice versa, strengthening the differences between the parasite and mammals. The established purification of a uniquely composed F1-ATPase is suitable for structure resolution by X-ray crystallography. Given the non-conventional function of F1-ATPase in BS and the F1-TbIF1 binding data, we propose that the structure could be exploited to design specific inhibitors for potential use in therapeutics.n

Druh

O - Ostatní výsledky

CEP obor

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OECD FORD obor

10608 - Biochemistry and molecular biology

Projekt

<a href="/cs/project/LL1205" target="_blank" >LL1205: Charakterizace unikátních vlastností esenciální FoF1 ATP syntázy u původce africké spavé nemoci Trypanosoma bucei za účelem vývoje inhibitorů tohoto komplexu.</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2014

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů