KEEG enrichment analysis showing the list of the top 20 pathways.

<p>The heatmap shows the list of the 20 pathways regulated in (1) ama <i>La</i>-arg^- vs ama <i>La</i>-WT, (2) ama <i>La</i>-arg^- vs pro <i>La</i>-arg^-, (3) ama <i>La</i>-WT vs pro <i>La</i>-WT and (4) pro <i>La</i>-arg^- vs pro <i>La</i>-WT. The enrichment map is colored by the gradient level of the p value. (pro) promastigote, (ama) axenic amastigote, (<i>La</i>-WT) <i>L</i>. <i>amazonensis</i> wild-type, (<i>La</i>-arg^-) <i>L</i>. <i>amazonensis</i> arginase knockout.</p

Transcriptional profiling of <i>La</i>-WT and <i>La</i>-arg^- promastigotes and axenic amastigotes.

<p>Venn diagram of the 1268 differentially expressed genes, showing the number of genes common and non-common from each sample and the number in the overlap. (pro) promastigote, (ama) axenic amastigote, (<i>La</i>-WT) <i>L</i>. <i>amazonensis</i> wild-type, (<i>La</i>-arg^-) <i>L</i>. <i>amazonensis</i> arginase knockout.</p

Crossing of transcriptome and metabolome profiles of the arginine pathway, highlighting the enzymes with differential gene expression based on the RNA-seq data.

<p>Representation of the arginine pathway and FPKM expression levels highlighting in gray boxes the enzymes with differential gene expression: (A) argininosuccinate synthase (EC6.3.4.5), (B) acetylornithine deacetylase (EC3.5.1.16), (C) glutamate 5-kinase (EC2.7.2.11), (D) spermidine synthase (EC2.5.1.16), (E) arginase (EC3.5.3.1), (F) pyrroline 5-carboxylase reductase (EC1.5.1.2) and (G) pyrroline 5-carbolylate dehydrogenase (EC1.2.1.88). The arrows indicate the increase or decrease levels, according to our RNA-seq data analyses and the metabolome fingerprints, previously described [<a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0006026#pntd.0006026.ref009" target="_blank">9</a>]. Each bar is represented from three independent biological replicates. Statistical analyses were performed using <i>t</i>-test. (*) p < 0.05.</p

Top 5 transcripts differentially expressed genes of <i>La</i>-WT and <i>La</i>-arg^- promastigotes and axenic amastigotes.

<p>Top 5 transcripts differentially expressed genes of <i>La</i>-WT and <i>La</i>-arg^- promastigotes and axenic amastigotes.</p

KEEG enrichment analyses of <i>La</i>-WT and <i>La</i>-arg^- promastigotes and axenic amastigotes of the following pathways: Biosynthesis of amino acids, arginine and proline metabolism and arginine biosynthesis.

<p>KEEG enrichment analyses of <i>La</i>-WT and <i>La</i>-arg^- promastigotes and axenic amastigotes of the following pathways: Biosynthesis of amino acids, arginine and proline metabolism and arginine biosynthesis.</p

Transcripts expression of enzymes involved in the L-arginine pathway in the comparison of <i>La</i>-WT and <i>La</i>-arg^- promastigotes and axenic amastigotes.

<p>Transcripts expression of enzymes involved in the L-arginine pathway in the comparison of <i>La</i>-WT and <i>La</i>-arg^- promastigotes and axenic amastigotes.</p

Arginase (LmxM.34.1480) transcript assembling and annotation.

<p>Total reads coverage aligned in the region of LmxM.34.1480 gene in the lines <i>La</i>-WT and <i>La</i>-arg^-promastigotes (pro) and axenic amastigotes (ama) of the previously annotated <i>L</i>. <i>mexicana</i> genome. (<i>La</i>-WT) <i>L</i>. <i>amazonensis</i> wild-type, (<i>La</i>-arg^-) <i>L</i>. <i>amazonensis</i> arginase knockout.</p

Schematic representation of <i>L</i>. <i>(L</i>.<i>) amazonensis</i> promastigote and amastigote NO production in the infection context.

<p>In <i>L</i>. <i>(L</i>.<i>) amazonensis</i>, the AAP3 transporter takes up L-arginine, and this amino acid is metabolized by arginase into ornithine to produce polyamines or via NOS-like to produce NO. <i>La</i>-WT-infected macrophages increase the activity of the polyamine pathway, increasing the expression of the L-arginine transporter from the host (CAT2B) and parasite (AAP3), arginase1 (host) and parasite-arginase to metabolizing L-arginine to produce polyamines, consequently sustaining the basal level of NOS2 expression and NO production. Indeed, the <i>La</i>-WT amastigote differentiation induces NOS-like expression and NO production, higher levels than promastigotes, but lower than those produced by macrophages. The lack of arginase activity in promastigotes increases the L-arginine levels, even that the reduction in AAP3 expression, inducing the expression of NOS-like, NO and citrulline production. The <i>La</i>-arg^—infected macrophages present lower levels of CAT2B and AAP3, which could reduce L-arginine uptake, and lower the levels of arginase 1 and polyamine production compared with <i>La</i>-WT infection allowing the increase in NOS2 expression and NO production, reducing infectivity. In addition, the <i>La</i>-arg^- amastigote differentiation induces NOS-like expression but not AAP3 expression and L-arginine uptake sufficient to increase NO production compared with <i>La</i>-WT promastigotes. PV: parasitophorous vacuole.</p

Oxidoreductase-like transcripts expression of <i>La</i>-WT and <i>La</i>-arg^- axenic amastigotes.

<p>Oxidoreductase-like transcripts expression of <i>La</i>-WT and <i>La</i>-arg^- axenic amastigotes.</p

Oxidoreductase-like transcripts expression of <i>La</i>-WT promastigotes and axenic amastigotes.

<p>Oxidoreductase-like transcripts expression of <i>La</i>-WT promastigotes and axenic amastigotes.</p