Decyl Gallate as a Possible Inhibitor of N-Glycosylation Process in Paracoccidioides lutzii

Abstract

The available antifungal therapeutic arsenal is limited. The search for alternative drugs with fewer side effects and new targets remains a major challenge. Decyl gallate (G14) is a derivative of gallic acid with a range of biological activities and broad-spectrum antifungal activity. Previously, our group demonstrated the promising anti-Paracoccidioides activity of G14. In this work, to evaluate the antifungal characteristics of G14 for Paracoccidioides lutzii, a chemical-genetic interaction analysis was conducted on a Saccharomyces cerevisiae model. N-glycosylation and/or the unfolded protein response pathway was identified as a high-confidence process for drug target prediction. The overactivation of unfolded protein response (UPR) signaling was confirmed using this model with IRE1/ATF6/PERK genes tagged with green fluorescent protein (GFP). In P. lutzii, this prediction was confirmed by the low activity of glycosylated enzymes [α-(1,3)-glucanase, N-acetyl-β-d-glucosaminidase (NAGase), and α-(1,4)-amylase], by hyperexpression of genes involved with the UPR and glycosylated enzymes, and by the reduction in the amounts of glycosylated proteins and chitin. All of these components are involved in fungal cell wall integrity and are dependent on the N-glycosylation process. This loss of integrity was confirmed by the reduction in mitochondrial activity, impaired budding, enhancement of wall permeability, and a decrease in viability. These events led to a reduction of the ability of fungi to adhere on human lung epithelial cells (A549) in vitro. Therefore, G14 may have an important role in balancing the inflammatory reaction caused by fungal infection, without interfering with the microbicidal activity of nitric oxide. This work provides new information on the activity of G14, a potential anti-Paracoccidioides compound.

Intracellular Protein Adsorption Behavior and Biological Effects of Polystyrene Nanoplastics in THP-1 Cells

“…Glucose-regulating protein 78 (GRP78) plays an important regulatory role in UPR . Under normal conditions when UPR is not activated, inactive GRP78 binds and forms a stable complex with activating transcription factor 6 (ATF6), protein kinase RNA-like endoplasmic reticulum kinase (PERK), and inositol-requiring enzyme 1 (IRE1)three ER transmembrane proteins that act as intracellular receptors for the UPR signal transduction pathway. , The accumulation of misfolded or unfolded proteins in the ER leads to dissociation of these three sensor proteins from GRP78; this leads to increased expression of GRP78, which, in turn, triggers the three parallel signaling pathways of UPR to protect the cell . Therefore, GRP78 can be employed as a marker to assess UPR activation in cells.…”

“…56,57 The accumulation of misfolded or unfolded proteins in the ER leads to dissociation of these three sensor proteins from GRP78; this leads to increased expression of GRP78, which, in turn, triggers the three parallel signaling pathways of UPR to protect the cell. 58 Therefore, GRP78 can be employed as a marker to assess UPR activation in cells. Adsorption studies suggested the adsorption of RPN1 onto NPs in THP-1 cells (Figure 4C).…”

Polypeptides Targeting Paracoccidioides brasiliensis Drk1

“…For glycosylated protein analysis, yeast cells were washed after the peptide treatments described above and stained with 100 µg/mL of ConA-Alexa Fluor 488 at 37 • C, 150 rpm for 1 h. Fungal cells were washed, resuspended in PBS, and analyzed using a BD FAC-SCanto flow cytometer. The mean fluorescence intensity of 10,000 cells in the fluorescein isothiocyanate channels was determined [37].…”

Overview of Antifungal Drugs against Paracoccidioidomycosis: How Do We Start, Where Are We, and Where Are We Going?

“…Potential compounds act as growth inhibitors against Paracoccidioides spp. in low concentrations ( Table S1 ), such as alkyl gallates (0.004–16 µg/mL), an N-Glycosylation inhibitor [ 38 , 39 ]; the thiosemicarbazone lapachol, which acts on the plasma membrane (0.01–0.1 µM) [ 40 ]; azasterol analogs (0.5–10 µM) [ 41 ] and hydrazone derivatives (0.1–5 µM) [ 42 ], as inhibitors of ergosterol biosynthesis. These compounds are less potent when compared to azole derivatives, such as itraconazole with a 0.003–0.05 µM MIC [ 33 ]; luliconazole, a topical antifungal repositioned against Paracoccidioides spp.…”