L-arginine and cationic amino acid transporter 2B regulate growth and survival of Leishmania amazonensis amastigotes in macrophages.

Amastigotes in Macrophages Leishmania amazonensis Survival of Transporter 2B Regulate Growth and l-Arginine and Cationic Amino Acid

L-arginine availability and arginase activity: Characterization of amino acid permease 3 in Leishmania amazonensis

BACKGROUND Leishmania uses the amino acid L-arginine as a substrate for arginase, enzyme that produces urea and ornithine, last precursor of polyamine pathway. This pathway is used by the parasite to replicate and it is essential to establish the infection in the mammalian host. L-arginine is not synthesized by the parasite, so its uptake occurs through the amino acid permease 3 (AAP3). AAP3 is...

Axenic Leishmania amazonensis Promastigotes Sense both the External and Internal Arginine Pool Distinctly Regulating the Two Transporter-Coding Genes

Leishmania (L.) amazonensis uses arginine to synthesize polyamines to support its growth and survival. Here we describe the presence of two gene copies, arranged in tandem, that code for the arginine transporter. Both copies show similar Open Reading Frames (ORFs), which are 93% similar to the L. (L.) donovani AAP3 gene, but their 5' and 3' UTR's have distinct regions. According to quantitative...

A Leishmania amazonensis ZIP family iron transporter is essential for parasite replication within macrophage phagolysosomes

Infection of mammalian hosts with Leishmania amazonensis depends on the remarkable ability of these parasites to replicate within macrophage phagolysosomes. A critical adaptation for survival in this harsh environment is an efficient mechanism for gaining access to iron. In this study, we identify and characterize LIT1, a novel L. amazonensis membrane protein with extensive similarity to IRT1, ...

Arginase expression modulates nitric oxide production in Leishmania (Leishmania) amazonensis

BACKGROUND Arginase is an enzyme that converts L-arginine to urea and L-ornithine, an essential substrate for the polyamine pathway supporting Leishmania (Leishmania) amazonensis replication and its survival in the mammalian host. L-arginine is also the substrate of macrophage nitric oxide synthase 2 (NOS2) to produce nitric oxide (NO) that kills the parasite. This competition can define the fa...