MNN9 — Aspergillus fumigatus

Summary

AFU2G01450 (AfMNN9, MNN9) on chromosome 2 of Aspergillus fumigatus encodes a putative alpha-1,6 mannosyltransferase subunit (Mnn9) with 1,6-alpha-mannosyltransferase, mannosyltransferase, and transglycosidase activities. The gene is associated with mannan and galactomannan anabolism, cell wall mannoprotein biosynthesis, protein N-linked glycosylation, and fungal-type cell wall organization. It localizes to the mannan polymerase II complex, cis-Golgi network, Golgi complex, and ER membrane. AfMNN9 is linked to numerous phenotypes including decreased spore germination, increased vegetative growth rate, increased biofilm formation, altered protein secretion and transport, increased hyperosmotic stress resistance, decreased freeze-thaw resistance, and abnormal endomembrane system morphology. Studies of related genes in other species connect the MNN9 family to flocculation, cell wall morphology, cell size, and oxidative stress response.