The mannosyltransferase Alg9 plays a vital role in N-linked protein glycosylation in Saccharomyces cerevisiae, but its function in most filamentous fungi is not clear. The present study characterized BbAlg9 (an ortholog of S. cerevisiae Alg9) in Beauveria bassiana to determine the roles of N-mannosyltransferase in biological control potential of the filamentous entomopathogenic fungus. The disruption of BbAlg9 led to slower fungal growth in media with various nutrition compositions. The conidiation of ΔBbAlg9 was less than that of the wild type from the third to the fifth day but showed no significant difference on the sixth day, suggesting that BbAlg9 affects the development of conidia rather than conidial yield of late stage. ΔBbAlg9 showed defects in conidial germination, multiple stress tolerances and the yield of blastospores, with altered size and density, and virulence in hosts infected via the immersion and injection methods. The deletion of BbAlg9 resulted in defects in cell wall integrity, including increased mannoprotein and glucan content and decreased chitin content, which were accompanied by transcriptional activation or suppression of genes related to cell wall component biosynthesis. Notably, deletion of the N-mannosyltransferase BbAlg9 altered the transcription levels of O-mannosyltransferase genes (Pmt and Ktr family). These data show that BbAlg9 is involved in the fungal development, conidial stress tolerance, cell wall integrity and virulence of B. bassiana.

甘露糖基转移酶 Alg9在酿酒酵母中的N连接蛋白糖基化中起着至关重要的作用，但其在大多数丝状真菌中的功能尚不清楚。本研究中，其特征在于BbAlg9（的同源物酿酒酵母中ALG9）白僵菌来确定角色的Ñ在丝状昆虫病原真菌生物防治潜力-mannosyltransferase。BbAlg9的破坏导致真菌在具有各种营养成分的培养基中生长缓慢。从第 3 天到第 5 天，Δ BbAlg9的分生孢子数小于野生型，但在第 6 天没有显着差异，表明BbAlg9影响分生孢子的发育而不是影响后期分生孢子的产量。Δ BbAlg9在分生孢子萌发、多重胁迫耐受性和芽生孢子产量方面表现出缺陷，大小和密度发生改变，以及通过浸泡和注射方法感染的宿主的毒力。BbAlg9的缺失导致细胞壁完整性缺陷，包括甘露糖蛋白和葡聚糖含量增加以及几丁质含量降低，同时伴有与细胞壁成分生物合成相关的基因的转录激活或抑制。值得注意的是，N-甘露糖基转移酶BbAlg9 的缺失改变了O-甘露糖基转移酶基因（Pmt 和 Ktr 家族）。这些数据表明，BbAlg9参与真菌发展，分生孢子抗逆性，细胞壁的完整性和毒力球孢白僵菌。