title: Inhibitor of cysteine peptidase does not influence the development of Leishmania mexicana in Lutzomyia longipalpis.
abstract: It has been proposed that the natural cysteine peptidase inhibitor ICP of Leishmania mexicana protects the protozoan parasite from insect host proteolytic enzymes, thereby promoting survival. To test this hypothesis, L. mexicana mutants deficient in ICP were evaluated for their ability to develop in the sand fly Lutzomyia longipalpis. No significant differences were found between the wild-type parasites, two independently derived ICP-deficient mutants, or mutants overexpressing ICP; all lines developed similarly in the sand fly midgut and produced heavy late-stage infections. In addition, recombinant L. mexicana ICP did not inhibit peptidase activity of the midgut extracts in vitro. We conclude that ICP has no major role in promoting survival of L. mexicana in the vectorial part of its life cycle in L. longipalpis.
authors.affiliation: Department of Parasitology, Faculty of Science, Charles University, Vinicna 7, 128 44 Prague 2, Czech Republic.
authors.forename: Lucie
authors.initials: L
authors.lastname: Jecna
authors.forename: Anna
authors.initials: A
authors.lastname: Svarovska
authors.forename: Sebastien
authors.initials: S
authors.lastname: Besteiro
authors.forename: Jeremy C
authors.initials: JC
authors.lastname: Mottram
authors.forename: Graham H
authors.initials: GH
authors.lastname: Coombs
authors.forename: Petr
authors.initials: P
authors.lastname: Volf
mesh_terms: D000818:Animals; D003546:Cysteine Endopeptidases / Q000502:physiology; D015853:Cysteine Proteinase Inhibitors / Q000235:genetics / Q000502:physiology*; D005260:Female; D006790:Host-Parasite Interactions; D019476:Insect Proteins / Q000502:physiology; D007894:Leishmania mexicana / Q000235:genetics / Q000472:pathogenicity*; D015800:Protozoan Proteins / Q000235:genetics / Q000502:physiology*; D011576:Psychodidae / Q000201:enzymology / Q000469:parasitology*
chemical_list: D015853:Cysteine Proteinase Inhibitors; D019476:Insect Proteins; D015800:Protozoan Proteins; D003546:Cysteine Endopeptidases