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bioRxiv · 10.64898/2026.03.27.714763

Identification, expression and subcellular localization of Leishmania amazonensis and Leishmania infantum Phospholipases A1

Abstract

Leishmaniases remain a significant global public health threat, with Leishmania amazonensis and Leishmania infantum representing the etiological agents of the cutaneous and visceral forms in the Americas, respectively. Building on our previous identification of Phospholipase A1 (PLA1) in Leishmania braziliensis, this study provides a comprehensive molecular, immunological, and biochemical characterization of PLA1 in L. amazonensis and L. infantum promastigotes. We analyzed PLA1 activity and expression, purified the recombinant enzyme from L. amazonensis, and validated protein expression using a specific anti-PLA1 serum. The major contribution of this research is the first description of the subcellular localization of a PLA1 within the Leishmania genus. Moreover, our results reveal an unprecedented association between PLA1 and lipid droplets within the parasites. This discovery is of particular interest as it provides the first evidence linking this enzyme to lipid storage organelles in Leishmania. Given that PLA1 is an established virulence factor in other trypanosomatids, these findings suggest a specialized role for the enzyme in parasite lipid metabolism and potentially in its pathogenic mechanisms, opening new perspectives for understanding Leishmania biology.

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BibTeXRIS

Lopez, S. A., de Souza Vieira, T. S., Trinitario, S. N., Pereira Dutra, F. S., Rajao, M. A., Risso, M. G., Sanchez Alberti, A., Bivona, A. E., Lauthier, J. J., Gimenez, G., Bozza, P. T., Belaunzaran, M. L.. 2026-03-27. Identification, expression and subcellular localization of Leishmania amazonensis and Leishmania infantum Phospholipases A1. https://doi.org/10.64898/2026.03.27.714763

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