0% non-fat dry
milk) for 1 hour followed by incubation with secondary anti-rabbit IgG conjugated with Alexa546. Samples were also stained with 0.1 μg / mL 4’,6-diamidino-2-phenylindole dihydrochloride (DAPI, from Sigma) at room temperature for 5 min before confocal microscopy. Parasite membrane fractionation and western blot analyses Aproximately 109 epimastigotes growing at a cell density of 2 × 107 parasites/mL were harvest, washed with saline buffer (PBS) and ressuspended in lysis buffer (Hepes 20mM; KCl 10 mM; MgCl2 1,5 mM; sacarose 250 mM; DTT 1 mM; PMSF 0,1 mM). After selleck products lysing cells with five cycles of freezing in liquid nitrogen and thawing at 37°C, an aliquot corresponding to total protein (T) extract was collected. Total cell lysate was centrifuged at a low speed (2,000 × g) for 10 min and the supernatant was subjected to ultracentrifugation (100,000 × g) for one hour. The resulting supernatant was collected and analysed as soluble, cytoplasmic fraction (C) whereas the pellet, corresponding to the membrane fraction (M) was ressuspended in lysis buffer. Volumes corresponding to 10 μg of total parasite protein extract (T), cytoplasmic (C) and membrane Selleck Torin 1 (M) fractions, mixed with Laemmli’s sample buffer, were loaded onto a 12% SDS–PAGE gel, transferred to Hybond-ECL membranes (GE HealthCare), blocked with 5.0% non-fat dry
milk and incubated with anti-GFP antibody (Santa Cruz Biotechnology) or anti-PEPCK antibody, followed by incubation with peroxidase conjugated anti-rabbit IgG and the ECL Plus reagent (GE HealthCare). Acknowledgements This study was supported by funds from Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, Brazil), Fundação de Amparo a pesquisa do Estado de Minas Gerais (FAPEMIG, Brazil)
and the Instituto Nacional de Ciência e Tecnologia de Vacinas (INCTV, Brazil). DCB, RAM and SMRT are recipients of CNPq fellowships; The work of WDDR, MMKM and LL is supported by Fundação Araucária, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Coordenação de Aperfeiçoamento de Pessoal de Nivel Superior (CAPES), PPSUS/MS and CNPq. Electronic supplementary material Additional file 1: Comparative Mannose-binding protein-associated serine protease sequence analysis of T. cruzi amastins. (Figure S1A) Percentages of amino acid identities among all T. cruzi amastin sequences present in the CL Brener and Sylvio X-10 genome databases. (Figure S1B) Conserved amino acid residues and conserved domains among sequences corresponding to all amastin genes present in the T. cruzi CL Brener genome are represented using the WebLogo software. The x axis depicts the amino acid position. The taller the letter the lesser the variability at the site. Predicted transmembrane domains are underlined. (PDF 433 KB) Additional file 2: Amino acid sequences of delta- and beta-amastins.