The genus Phytomonas comprises trypanosomatids that can parasitize a broad range of plant species. These fagellates can cause diseases in some plant families with a wide geographic distribution, which can result in great economic losses. We have demonstrated previously that Phytomonas serpens 15T, a tomato trypanosomatid, shares antigens with Trypanosoma cruzi, the agent of human Chagas disease. Herein, two-dimensional gel electrophoresis (2-DE) and mass spectrometry (MS) were used to identify proteins of P. serpens 15T that are recognized by sera from patients with Chagas disease. After 2D-electrophoresis of whole-cell lysates, 31 peptides were selected and analyzed by tandem mass spectrometry. Twenty-eight polypeptides were identifed, resulting in 22 different putative proteins. The identifed proteins were classifed into 8 groups according to biological process, most of which were clustered into a cellular metabolic process category. These results generated a collection of proteins that can provide a starting point to obtain insights into antigenic cross reactivity among trypanosomatids and to explore P. serpens antigens as candidates for vaccine and immunologic diagnosis studies.

Tools for the genetic manipulation of Trypanosoma cruzi are largely unavailable, although several vectors for transfection of epimastigotes and expression of foreign or recombinant genes have been developed. We have previously constructed several plasmid vectors in which recombinant genes are expressed in T. cruzi using the rRNA promoter. In this report, we demonstrate that one of these vectors can simultaneously mediate expression of neomycin phosphotransferase and green fluorescent protein when used to stably transfect cultured epimastigotes. These stably transfected epimastigotes can be selected and cloned as unique colonies on solid medium. We describe a simple colony PCR approach to the screening of these T. cruzi colonies for relevant genes. Thus, the methodologies outlined herein provide important new tools for the genetic dissection of this important parasite.

TTV é um vírus DNA recentemente descoberto no Japão a partir de um paciente portador de hepatite pós-transfusional de origem desconhecida. Neste estudo, avaliamos a presença deste vírus em pacientes com hepatopatias crônicas dos estados de São Paulo e do Pará, representando duas regiões geograficamente diferentes. O DNA do TTV foi encontrado em 21/105 (20%) e 9/20 (45%) dos casos de São Paulo e do Pará, respectivamente. O seqüenciamento do DNA amplificado confirmou a presença dos genótipos 1a e 2a , bem como de outros genótipos ainda não descritos até o momento. Em conclusão, TTV está presente em casos de hepatopatias crônicas do Sudeste e do Norte do Brasil. Por outro lado, maiores estudos ainda são necessários antes de se estabelecer relação causal entre o TTV e a hepatite em seres humanos.

TTV is a recently discovered DNA virus, isolated from a patient with post-transfusion hepatitis of unknown etiology by Japanese researchers. In the present study, we evaluated the presence of TTV among chronic liver diseases patients in São Paulo and Pará states, representing two geographically distinct Brazilian regions. TTV DNA was found in 21/105 (20%) and 9/20 (45%) cases from São Paulo and Pará States, respectively. DNA sequence data confirmed the presence of TTV genotypes 1a and 2a, as well as other genotypes not yet described. In conclusion, TTV is present in chronic liver diseases cases from Southeast and North Brazil. However, further studies involving healthy populations are necessary before establishing any causal relationship among TTV and human hepatitis.