Lipid Signaling

Sphingolipid signaling through protein kinase C (PKC) also regulates virulence in Cn. The lipid signaling molecule diacylglycerol (DAG) is generated by the enzyme inositol phosphoryl ceramide synthase (Ipc1) (Shea & Del Poeta, 2006). DAG regulates the activity of laccase, possibly through activation of PKC. Thus, strains with reduced Ipc1 have corresponding defects in melanization (Heung et al., 2004). Ipc1 is a fungal-specific enzyme that is essential in Cn. Reducing the expression of Ipc1

leads to defects in virulence, such as decreased survival in macrophages in vitro and attenuated virulence in vivo (Luberto et al., 2001). A second mechanism of action of Ipcl (through DAG) is regulation of the expression of Appl (antiphago-cytic protein), a secreted protein that inhibits phagocytosis by macrophages (Luberto et al., 2003; Mare et al., 2005).

The phosphoryl inositol group of IPC can be removed by inositol phosphosphin-golipid phospholipase C (Iscl) (Shea et al., 2006). Cn strains lacking Iscl have decreased fungal burden in the brain of immunocompetent mice, suggesting a role for this gene in dissemination to the brain. In addition, the iscl strain is highly susceptible to killing by macrophages in vitro and hypersensitive to oxidative and nit-rosative stresses compared to wild type (Shea et al., 2006).

Cure Your Yeast Infection For Good

Cure Your Yeast Infection For Good

The term vaginitis is one that is applied to any inflammation or infection of the vagina, and there are many different conditions that are categorized together under this ‘broad’ heading, including bacterial vaginosis, trichomoniasis and non-infectious vaginitis.

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