LmxM.22.0250-Encoded Dual Specificity Protein/Lipid Phosphatase Impairs Leishmania mexicana Virulence In Vitro

Abstract

Protein phosphorylation/dephosphorylation is an important regulatory mechanism that controls many key physiological processes. Numerous pathogens successfully use kinases and phosphatases to internalize, replicate, and survive, modifying the host′s phosphorylation profile or signal transduction pathways. Multiple phosphatases and kinases from diverse bacterial pathogens have been implicated in human infections before. In this work, we have identified and characterized the dual specificity protein/lipid phosphatase LmDUSP1 as a novel virulence factor governing Leishmania mexicana infection. The LmDUSP1-encoding gene (LmxM.22.0250 in L. mexicana) has been acquired from bacteria via horizontal gene transfer. Importantly, its orthologues have been associated with virulence in several bacterial species, such as Mycobacterium tuberculosis and Listeria monocytogenes. Leishmania mexicana with ablated LmxM.22.0250 demonstrated severely attenuated virulence in the experimental infection of primary mouse macrophages, suggesting that this gene facilitates Leishmania pathogenicity in vertebrates. Despite significant upregulation of LmxM.22.0250 expression in metacyclic promastigotes, its ablation did not affect the ability of mutant cells to differentiate into virulent stages in insects. It remains to be further investigated which specific biochemical pathways involve LmDUSP1 and how this facilitates the parasite′s survival in the host. One of the interesting possibilities is that LmDUSP1 may target host′s substrate(s), thereby affecting its signal transduction pathways.

Catalase impairs Leishmania mexicana development and virulence

“…The L. mexicana -mCHERRY cells were differentiated in vitro [ 85 ] and mCHERRY expression was assayed by RT-qPCR (S3B Fig) and Western blotting (S3C Fig). The differentiation was controlled by RT-qPCR analysis of the selected marker genes PFR1D, SHERP , and AMASTIN for promastigotes (both pro- and metacyclic), metacyclic promastigotes, and amastigotes, respectively [ 86 ] and compared to the wild type L. mexicana cells (S5 Fig, panels A and B), confirming no major defect in differentiation in vitro . While the mCHERRY RNA level was stable, we noticed a drop in mCHERRY protein level in amastigotes.…”

Large-Scale Phylogenetic Analysis of Trypanosomatid Adenylate Cyclases Reveals Associations with Extracellular Lifestyle and Host–Pathogen Interplay

“…L . mexicana promastigotes (MNYC/BZ/62/M379) were cultivated in complete M199 medium and transfected as described previously ( Kraeva et al. 2019 ).…”

Metabolic Changes of Mycobacterium tuberculosis during the Anti-Tuberculosis Therapy

“…At the same time, the level of the Rv2228c transcript was higher in the 3955 strain, compared to the RUS_B0. It is known that PtpA (Rv2234) and PtpB (Rv0153c) are secreted proteins, which play an important role in the pathogen interaction with the host cell [30] and have orthologs among other pathogenic pro-and eukaryotes [31]. Rv2228c is presumably involved in bacterial replication, as it is only authenticated RNase HI in M. tuberculosis.…”