title: Analysis of the NTPDase and ecto-5'-nucleotidase profiles in serum-limited Trichomonas vaginalis.
abstract: Trichomonas vaginalis is a parasite of the human urogenital tract that causes trichomonosis, the most prevalent non-viral sexually transmitted disease. Ectonucleoside triphosphate diphosphohydrolase (NTPDase) family members, which hydrolyse extracellular ATP and ADP and ecto-5'-nucleotidase, which hydrolyses AMP, have been characterised in T. vaginalis. For trichomonad culture, the growth medium is supplemented with 10% serum, which is an important source of nutrients, such as adenosine. Here, we investigated the ATP metabolism of T. vaginalis trophozoites from long-term cultures and clinical isolates under limited bovine serum conditions (1% serum). The specific enzymatic activities were expressed as nmol inorganic phosphate (Pi) released/min/mg protein, the gene expression patterns were determined by reverse transcriptase-polymerase chain reaction, the extracellular adenine nucleotide hydrolysis was analysed by high performance liquid chromatography and the cell cycle analysis was assessed by flow cytometry. Serum limitation led to the profound activation of NTPDase and ecto-5'-nucleotidase activities. Furthermore, the levels of NTPDase A and B transcripts increased and extracellular ATP metabolism was activated, which led to enhanced ATP hydrolysis and the formation of ADP and AMP. Moreover, the cell cycle was arrested at the G0/G1 stage, which suggested adenosine uptake. Our data suggest that under conditions of serum limitation, NTPDase and ecto-5'-nucleotidase play a role in providing the adenosine required for T. vaginalis growth and that this process contributes to the establishment of parasitism.
authors.affiliation: Laboratório de Pesquisa em Parasitologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brasil.
authors.forename: Amanda Piccoli
authors.initials: AP
authors.lastname: Frasson
authors.forename: Mariele Feiffer
authors.initials: MF
authors.lastname: Charão
authors.forename: Denis Broock
authors.initials: DB
authors.lastname: Rosemberg
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: de Souza
authors.forename: Solange Cristina
authors.initials: SC
authors.lastname: Garcia
authors.forename: Cristina
authors.initials: C
authors.lastname: Bonorino
authors.forename: Maurício Reis
authors.initials: MR
authors.lastname: Bogo
authors.forename: Geraldo Attilio
authors.initials: GA
authors.lastname: De Carli
authors.forename: Tiana
authors.initials: T
authors.lastname: Tasca
mesh_terms: D015720:5'-Nucleotidase / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D015703:Antigens, CD / Q000378:metabolism*; D001081:Apyrase / Q000378:metabolism*; D002417:Cattle; D002453:Cell Cycle; D002851:Chromatography, High Pressure Liquid; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014246:Trichomonas vaginalis / Q000201:enzymology*
chemical_list: D015703:Antigens, CD; D000255:Adenosine Triphosphate; D015720:5'-Nucleotidase; D001081:Apyrase; C067869:CD39 antigen