Deletion of the α-(1,3)-Glucan Synthase Genes Induces a Restructuring of the Conidial Cell Wall Responsible for the Avirulence of Aspergillus fumigatus

PLoS Pathogens

Michel Chignard¹  Viviane Balloy¹  Jean-Paul Latgé²  Silvia Bozza²  Céline Formosa³  Luigina Romani⁴  Olaf Kniemeyer⁴  Etienne Dague⁵  Christine Henry⁶  Axel A. Brakhage⁶  Robert W. Roberson⁷  Anne Beauvais⁷ 

[1] CNRS, LAAS, Toulouse, France;Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Perugia, Italy;Integrated Research and Treatment Center, Center for Sepsis Control and Care Jena, University Hospital (CSCC), Jena, Germany;Molecular and Applied Microbiology, Leibniz-Institute for Natural Product Research and Infection Biology (HKI), University of Jena, Jena, Germany;School of Life Sciences, Arizona State University, Tempe, Arizona, United States of America;Unité de Défence Innée et Inflammation, Institut Pasteur, Inserm U874, Paris, France;Unité des Aspergillus, Institut Pasteur, Paris, France

关键词: Cell walls;    Macrophages;    Aspergillus fumigatus;    Immune response;    Protein extraction;    Mutant strains;    Alveolar macrophages;    Phagocytosis;   

DOI  :  10.1371/journal.ppat.1003716

学科分类：生物科学（综合）

来源: Public Library of Science

【 摘 要 】

α-(1,3)-Glucan is a major component of the cell wall of Aspergillus fumigatus, an opportunistic human fungal pathogen. There are three genes (AGS1, AGS2 and AGS3) controlling the biosynthesis of α-(1,3)-glucan in this fungal species. Deletion of all the three AGS genes resulted in a triple mutant that was devoid of α-(1,3)-glucan in its cell wall; however, its growth and germination was identical to that of the parental strain in vitro. In the experimental murine aspergillosis model, this mutant was less pathogenic than the parental strain. The AGS deletion resulted in an extensive structural modification of the conidial cell wall, especially conidial surface where the rodlet layer was covered by an amorphous glycoprotein matrix. This surface modification was responsible for viability reduction of conidia in vivo, which explains decrease in the virulence of triple agsΔ mutant.

【 授权许可】

CC BY