ARTICLE Chemical shift assignments and secondary structure prediction for Q4DY78, a conserved kinetoplastid-specific protein from Trypanosoma cruzi E ´ verton Dias D’Andre ´a 1 • Anne Diehl 2 • Peter Schmieder 2 • Hartmut Oschkinat 2 • Jose ´ Ricardo Pires 1 Received: 18 April 2016 / Accepted: 22 June 2016 / Published online: 29 June 2016 Ó Springer Science+Business Media Dordrecht 2016 Abstract Trypanosoma cruzi, Trypanosma brucei and Leishmania spp. are kinetoplastid protozoa causative agents of Chagas disease, sleeping sickness and leishmaniasis, respectively, neglected tropical diseases estimated to infect millions of people worldwide. Their genome sequencing has revealed approximately 50 % of genes encoding hypotheti- cal proteins of unknown function, opening possibilities for novel target identification and drug discovery. Q4DY78 is a putative essential protein from T. cruzi conserved in the related kinetoplastids and divergent from mammalian host proteins. Here we report the 1 H, 15 N, and 13 C chemical shift assignments and secondary structure analysis of the Q4DY78 protein as basis for NMR structure determination, functional analysis and drug screening. Keywords Hypothetical protein Q4DY78 Á Trypanosoma cruzi Á Kinetoplastids Á Neglected diseases Á NMR assignments Biological context Chagas disease is caused by the protozoan parasite Try- panosoma cruzi. T. cruzi belongs to the order kinetoplas- tida and is evolutionarily related to the species Trypanosoma brucei and Leishmania spp., causal agents of Sleeping Sickness and Leishmaniasis, respectively (Stuart et al. 2008). These disorders are among the so called Neglected Diseases. Their global prevalences are 8–9, 0.3, and 12 million people, and the population at risk is 25, 60, and 350 million, respectively (Hotez et al. 2007). Chagas disease was first described in 1909, by Carlos Chagas (Chagas 1909), and it is found mainly in endemic areas of 21 Latin American countries. Only in Colombia, the annual medical care costs with Chagas disease patients were estimated to be about US$ 267 million in 2008 (WHO 2015). The complete genomes of these three human pathogens have been sequenced (El-Sayed et al. 2005; Berriman et al. 2005; Ivens et al. 2005). Approximately 20,000 genes have been identified and about 50 % of these encode hypothetical proteins with unknown function which open possibilities to develop new therapies for these infections. There are no vaccines to prevent these disorders and the drugs currently available are inadequate because of resistance and toxicity. Conserved proteins in the three parasites, kinetoplastid-specific or which are sufficiently divergent from mammalian host proteins are interesting potentially new targets for drug development to control these three neglected diseases (El-Sayed et al. 2005). Q4DY78 (Uniprot accession code) is a small, 106 amino acid residues protein, conserved in Trypanosoma cruzi, Trypanosoma brucei, and Leishmania major, kinetoplastid- specific and thus unrelated to mammal proteins. An ortholog gene in T. brucei (Tb927.8.6430) with 76 % of sequence identity to Q4DY78, was proven to be essential in both, bloodstream and procyclic forms, as well as in the differentiation of procyclic to bloodstream form of T. brucei, as evaluated by means of RNA interference tech- nique (Alsford et al. 2011). Moreover, in a proteomic study of T. brucei strain 427, this ortholog was localized in a & Jose ´ Ricardo Pires jrmpires@cnrmn.bioqmed.ufrj.br 1 Instituto de Bioquı ´mica Me ´dica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Av. Carlos Chagas Filho, 373 - Bloco E, sala 10, Rio de Janeiro, RJ 21941-902, Brazil 2 Leibniz-Institut fu ¨r Molekulare Pharmakologie, Robert- Ro ¨ssle-Straße 10, 13125 Berlin, Germany 123 Biomol NMR Assign (2016) 10:325–328 DOI 10.1007/s12104-016-9693-8