Conidium Specific Polysaccharides in <i>Aspergillus fumigatus</i>

oleh: Zhonghua Liu, Isabel Valsecchi, Rémy A. Le Meur, Catherine Simenel, J. Iñaki Guijarro, Catherine Comte, Laetitia Muszkieta, Isabelle Mouyna, Bernard Henrissat, Vishukumar Aimanianda, Jean-Paul Latgé, Thierry Fontaine

Format: Article
Diterbitkan: MDPI AG 2023-01-01

Deskripsi

Earlier studies have shown that the outer layers of the conidial and mycelial cell walls of <i>Aspergillus fumigatus</i> are different. In this work, we analyzed the polysaccharidome of the resting conidial cell wall and observed major differences within the mycelium cell wall. Mainly, the conidia cell wall was characterized by (i) a smaller amount of α-(1,3)-glucan and chitin; (ii) a larger amount of β-(1,3)-glucan, which was divided into alkali-insoluble and water-soluble fractions, and (iii) the existence of a specific mannan with side chains containing galactopyranose, glucose, and N-acetylglucosamine residues. An analysis of <i>A. fumigatus</i> cell wall gene mutants suggested that members of the fungal GH-72 transglycosylase family play a crucial role in the conidia cell wall β-(1,3)-glucan organization and that α-(1,6)-mannosyltransferases of GT-32 and GT-62 families are essential to the polymerization of the conidium-associated cell wall mannan. This specific mannan and the well-known galactomannan follow two independent biosynthetic pathways.