TY - JOUR
T1 - Disruption of protein rhamnosylation affects the Sporothrix schenckii-host interaction
AU - Tamez-Castrellón, Alma K.
AU - van der Beek, Samantha L.
AU - López-Ramírez, Luz A.
AU - Martínez-Duncker, Iván
AU - Lozoya-Pérez, Nancy E.
AU - van Sorge, Nina M.
AU - Mora-Montes, H. ctor M.
N1 - Funding Information: We thank Prof. Gordon Brown from the University of Aberdeen for the donation of the IgG Fc-Dectin-1 chimera. This work was supported by Consejo Nacional de Ciencia y Tecnología (ref. FC 2015-02-834 and CF-2019-6380), and Red Temática Glicociencia en Salud (CONACYT-México). This work was supported by a Vidi grant (91713303) from the Dutch Research Council (NWO) to N.M.v.S and S.v.d.B. The authors declare no conflict of interest. Funding Information: We thank Prof. Gordon Brown from the University of Aberdeen for the donation of the IgG Fc-Dectin-1 chimera. This work was supported by Consejo Nacional de Ciencia y Tecnolog?a (ref. FC 2015-02-834 and CF-2019-6380), and Red Tem?tica Glicociencia en Salud (CONACYT-M?xico). This work was supported by a Vidi grant (91713303) from the Dutch Research Council (NWO) to N.M.v.S and S.v.d.B. The authors declare no conflict of interest. Publisher Copyright: © 2021 The Author(s)
PY - 2021/12/1
Y1 - 2021/12/1
N2 - Sporotrichosis is a fungal disease caused by the members of the Sporothrix pathogenic clade, and one of the etiological agents is Sporothrix schenckii. The cell wall of this organism has been previously analyzed and thus far is known to contain an inner layer composed of chitin and β -glucans, and an outer layer of glycoproteins, which are decorated with mannose and rhamnose-containing oligosaccharides. The L-rhamnose biosynthesis pathway is common in bacteria but rare in members of the Fungi kingdom. Therefore, in this study, we aimed to disrupt this metabolic route to assess the contribution of rhamnose during the S. schenckii-host interaction. We identified and silenced in S. schenckii a functional ortholog of the bacterial rmlD gene, which encodes for an essential reductase for the synthesis of nucleotide-activated L-rhamnose. RmlD silencing did not affect fungal growth or morphology but decreased cell wall rhamnose content. Compensatory, the β-1,3-glucan levels increased and were more exposed at the cell surface. Moreover, when incubated with human peripheral blood mononuclear cells, the RmlD silenced mutants differentially stimulated cytokine production when compared with the wild-type strain, reducing TNFα and IL-6 levels and increasing IL-1 β and IL-10 production. Upon incubation with human monocyte-derived macrophages, the silenced strains were more efficiently phagocytosed than the wild-type strain. In both cases, our data suggest that rhamnose-based oligosaccharides are ligands that interact with TLR4. Finally, our findings showed that cell wall rhamnose is required for the S. schenckii virulence in the G. mellonella model of infection.
AB - Sporotrichosis is a fungal disease caused by the members of the Sporothrix pathogenic clade, and one of the etiological agents is Sporothrix schenckii. The cell wall of this organism has been previously analyzed and thus far is known to contain an inner layer composed of chitin and β -glucans, and an outer layer of glycoproteins, which are decorated with mannose and rhamnose-containing oligosaccharides. The L-rhamnose biosynthesis pathway is common in bacteria but rare in members of the Fungi kingdom. Therefore, in this study, we aimed to disrupt this metabolic route to assess the contribution of rhamnose during the S. schenckii-host interaction. We identified and silenced in S. schenckii a functional ortholog of the bacterial rmlD gene, which encodes for an essential reductase for the synthesis of nucleotide-activated L-rhamnose. RmlD silencing did not affect fungal growth or morphology but decreased cell wall rhamnose content. Compensatory, the β-1,3-glucan levels increased and were more exposed at the cell surface. Moreover, when incubated with human peripheral blood mononuclear cells, the RmlD silenced mutants differentially stimulated cytokine production when compared with the wild-type strain, reducing TNFα and IL-6 levels and increasing IL-1 β and IL-10 production. Upon incubation with human monocyte-derived macrophages, the silenced strains were more efficiently phagocytosed than the wild-type strain. In both cases, our data suggest that rhamnose-based oligosaccharides are ligands that interact with TLR4. Finally, our findings showed that cell wall rhamnose is required for the S. schenckii virulence in the G. mellonella model of infection.
KW - Cell wall
KW - Galleria mellonella
KW - Immune recognition
KW - Phagocytosis
KW - TLR4
KW - Virulence
KW - β-glucan
UR - http://www.scopus.com/inward/record.url?scp=85117739659&partnerID=8YFLogxK
U2 - https://doi.org/10.1016/j.tcsw.2021.100058
DO - https://doi.org/10.1016/j.tcsw.2021.100058
M3 - Article
C2 - 34308006
SN - 2468-2330
VL - 7
JO - The Cell Surface
JF - The Cell Surface
M1 - 100058
ER -