{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T03:04:09Z","timestamp":1792033449089,"version":"4.4.0"},"reference-count":40,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,4,22]],"date-time":"2026-04-22T00:00:00Z","timestamp":1776816000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003593","name":"Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnologico","doi-asserted-by":"crossref","award":["310670\/2021-7"],"award-info":[{"award-number":["310670\/2021-7"]}],"id":[{"id":"10.13039\/501100003593","id-type":"DOI","asserted-by":"crossref"}]},{"award":["310670\/2021-7"],"award-info":[{"award-number":["310670\/2021-7"]}],"id":[{"id":"https:\/\/ror.org\/03swz6y49","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002322","name":"Coordena\u00e7\u00e3o de Aperfei\u00e7oamento de Pessoal de N\u00edvel Superior","doi-asserted-by":"publisher","award":["0012017"],"award-info":[{"award-number":["0012017"]}],"id":[{"id":"10.13039\/501100002322","id-type":"DOI","asserted-by":"publisher"}]},{"award":["0012017"],"award-info":[{"award-number":["0012017"]}],"id":[{"id":"https:\/\/ror.org\/00x0ma614","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004586","name":"Funda\u00e7\u00e3o Carlos Chagas Filho de Amparo \u00e0 Pesquisa do Estado do Rio de Janeiro","doi-asserted-by":"publisher","award":["E-26\/201.136\/2021"],"award-info":[{"award-number":["E-26\/201.136\/2021"]}],"id":[{"id":"10.13039\/501100004586","id-type":"DOI","asserted-by":"publisher"}]},{"award":["E-26\/201.136\/2021"],"award-info":[{"award-number":["E-26\/201.136\/2021"]}],"id":[{"id":"https:\/\/ror.org\/03kk0s825","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Inorganic phosphate (Pi) is an essential nutrient required for energy metabolism, macromolecule biosynthesis, and signal transduction. Protozoan parasites are exposed to pronounced fluctuations in nutrient availability throughout their life cycles and therefore rely on adaptive strategies to secure phosphate from diverse host and environmental niches. This review summarizes current knowledge on phosphate acquisition mechanisms in protozoan parasites, with emphasis on membrane transport systems and extracellular phosphate-releasing enzymatic activities. Phosphate transport systems energized by proton or sodium gradients have been functionally characterized in several protozoan species, and in many cases phosphate uptake capacity is modulated by extracellular Pi availability. In addition, ectophosphatases expressed at the parasite surface contribute to phosphate acquisition by hydrolyzing extracellular phosphorylated substrates and releasing inorganic phosphate that can be subsequently internalized and metabolically utilized. Although phosphate-dependent regulation of ectophosphatase activity has been demonstrated in a more limited number of species, available evidence supports a functional interplay between extracellular phosphate scavenging and transmembrane transport, particularly under phosphate-limiting conditions. Despite these advances, the molecular mechanisms underlying phosphate sensing and regulatory coordination in protozoan parasites remain poorly understood. This review provides a comparative overview of phosphate transport systems and extracellular phosphate-scavenging enzymes in protozoan parasites, highlighting current evidence and remaining knowledge gaps.<\/jats:p>","DOI":"10.3390\/ijms27093707","type":"journal-article","created":{"date-parts":[[2026,4,22]],"date-time":"2026-04-22T09:01:24Z","timestamp":1776848484000},"page":"3707","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Phosphate Acquisition in Protozoan Parasites: Transport Systems, and Extracellular Phosphate-Releasing Enzymatic Activities"],"prefix":"10.3390","volume":"27","author":[{"given":"Anita Leocadio","family":"Freitas-Mesquita","sequence":"first","affiliation":[{"name":"Centro de Ci\u00eancias da Sa\u00fade, Instituto de Bioqu\u00edmica M\u00e9dica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-590, RJ, Brazil"},{"name":"Instituto Nacional de Ci\u00eancia e Tecnologia em Biologia Estrutural e Bioimagem, Rio de Janeiro 21941-590, RJ, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jos\u00e9 Roberto","family":"Meyer-Fernandes","sequence":"additional","affiliation":[{"name":"Centro de Ci\u00eancias da Sa\u00fade, Instituto de Bioqu\u00edmica M\u00e9dica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-590, RJ, Brazil"},{"name":"Instituto Nacional de Ci\u00eancia e Tecnologia em Biologia Estrutural e Bioimagem, Rio de Janeiro 21941-590, RJ, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"17289","DOI":"10.1074\/jbc.M312202200","article-title":"Intracellular Phosphate Serves as a Signal for the Regulation of the PHO Pathway in Saccharomyces cerevisiae","volume":"279","author":"Auesukaree","year":"2004","journal-title":"J. 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