Chitin synthase (primary fungal cell wall synthesis enzyme) (CHS)

Fungal cell wall synthesis enzymes are a broad class of membrane-associated enzymes responsible for polymerizing the main structural polysaccharides of the fungal cell wall, chiefly β-1,3-glucan synthase and chitin synthase[1][3][7]. These enzymes use nucleotide-activated sugar donors (e.g., UDP-glucose for glucan synthase, UDP-N-acetylglucosamine for chitin synthase) to assemble long polysaccharide chains that constitute the load-bearing scaffold of the fungal cell wall[1][3]. The enzymes play essential roles in fungal viability, shape, division, and pathogenicity, and their activities are modulated dynamically in response to environmental cues and cellular stress[4][7]. As these enzymes and their products are absent in humans, they are key targets of antifungal drugs such as echinocandins (β-1,3-glucan synthase inhibitors) and nikkomycin Z or polyoxins (chitin synthase inhibitors)[3][6]. The inhibition of these enzymes compromises fungal cell wall integrity, leading to cell lysis and death. Mutations in the corresponding genes (such as FKS1/FKS2 for glucan synthase and multiple CHS genes for chitin synthase) can confer antifungal drug resistance or alter cell wall composition, complicating treatment. These enzymes are widely conserved among medically relevant fungi including *Candida*, *Aspergillus*, and *Cryptococcus* species[3][7]. Important caveat: "Fungal cell wall synthesis enzyme" is a general description, not a specific molecular entity. The canonical molecular targets for antifungal drug discovery and clinical intervention are β-1,3-glucan synthase and chitin synthase, each encoded by multigene families (not a single molecule)[3][7]. This entry covers both as they are often collectively referred to in literature on antifungal targets, but specific target mapping should use their distinct names for structured data. Rationale for 'is_incorrect': - The term provided is overly broad and non-standard; specific enzymes like "β-1,3-glucan synthase" or "chitin synthase" are the canonical, actionable therapeutic targets in this context[3][6]. - Use of the generic label causes ambiguity and should be refined for structured data applications.

Other names

Fungal cell wall glucan synthaseβ-1,3-glucan synthaseβ-glucan synthaseCell wall biosynthetic enzymeGlucan synthase complexChitin synthaseFKS1/FKS2 (for β-1,3-glucan synthase gene products)

Inhibition of β-1,3-glucan synthesis (echinocandins) Inhibition of chitin synthesis (nikkomycin Z, polyoxins)