Unité des Aspergillus, Institut Pasteur, 75015 Paris, France; email:
Department of Clinical Microbiology and Microbial Pathogenesis, University of Crete, Heraklion, Crete 74100, Greece.
Annu Rev Microbiol. 2017 Sep 8;71:99-116. doi: 10.1146/annurev-micro-030117-020406. Epub 2017 Jul 12.
More than 90% of the cell wall of the filamentous fungus Aspergillus fumigatus comprises polysaccharides. Biosynthesis of the cell wall polysaccharides is under the control of three types of enzymes: transmembrane synthases, which are anchored to the plasma membrane and use nucleotide sugars as substrates, and cell wall-associated transglycosidases and glycosyl hydrolases, which are responsible for remodeling the de novo synthesized polysaccharides and establishing the three-dimensional structure of the cell wall. For years, the cell wall was considered an inert exoskeleton of the fungal cell. The cell wall is now recognized as a living organelle, since the composition and cellular localization of the different constitutive cell wall components (especially of the outer layers) vary when the fungus senses changes in the external environment. The cell wall plays a major role during infection. The recognition of the fungal cell wall by the host is essential in the initiation of the immune response. The interactions between the different pattern-recognition receptors (PRRs) and cell wall pathogen-associated molecular patterns (PAMPs) orientate the host response toward either fungal death or growth, which would then lead to disease development. Understanding the molecular determinants of the interplay between the cell wall and host immunity is fundamental to combatting Aspergillus diseases.
超过 90%的丝状真菌烟曲霉的细胞壁由多糖组成。细胞壁多糖的生物合成受三种类型的酶控制：跨膜合成酶，它与质膜锚定，并以核苷酸糖为底物；细胞壁相关的转糖基酶和糖苷水解酶，负责重塑新合成的多糖并建立细胞壁的三维结构。多年来，细胞壁被认为是真菌细胞的惰性外壳。现在，细胞壁被认为是一个活的细胞器，因为当真菌感知到外部环境的变化时，不同组成细胞壁成分（尤其是外层）的组成和细胞定位会发生变化。细胞壁在感染过程中起着重要作用。宿主对真菌细胞壁的识别是免疫反应启动的关键。不同模式识别受体（PRRs）与细胞壁病原体相关分子模式（PAMPs）之间的相互作用将宿主反应导向真菌的死亡或生长，从而导致疾病的发展。了解细胞壁与宿主免疫之间相互作用的分子决定因素对于对抗曲霉菌病至关重要。
