Calcineurin-dependent galactomannan release in Aspergillus fumigatus.
Calcineurin-dependent galactomannan release in Aspergillus fumigatus.
复制标题
烟曲霉中钙依赖磷酸酶依赖性半乳甘露聚糖的释放。
DOI：
10.1007/s10096-010-1118-5
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
Steinbach,WJ
中科院分区：
文献类型：
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作者：
Mennink-Kersten,MASH;Ruegebrink,D;Verweij,PE;Steinbach,WJ
推荐使用半乳甘露聚糖测定来诊断侵袭性曲霉病并在临床上使用，但烟曲霉释放半乳甘露聚糖的机制尚不清楚。我们用的是A。缺乏钙调神经磷酸酶 A (cnaA) 的 fumigatus 菌株，已被证明对致病性至关重要，可用于评估半乳甘露聚糖动力学。在对数生长期，当葡萄糖被消耗时，β-D-呋喃半乳糖苷（galf）-抗原在培养物中释放。然而，在葡萄糖受到限制后，野生型菌株上清液中的GM释放进一步增加，而ΔcnaAstrain中的GM释放没有进一步增加。 ΔcnaA突变体中的β-呋喃半乳糖苷酶活性也降低，并且ΔcnaA突变体的细胞壁部分中半乳糖抗原的量大约高十倍。这表明抗原可能由于细胞壁异常而无法释放。这项工作和之前的工作表明，在生长期间存在动态的钙调磷酸酶依赖性细胞壁，细胞壁中的半乳甘露聚糖释放可能是钙调磷酸酶依赖性的，并反映在GM释放减少和ΔcnaA突变体galfin的细胞壁分数大大增加。
The galactomannan assay to diagnose invasive aspergillosis is recommended and clinically utilized, yet the mechanism of galactomannan release fromAspergillus fumigatusis unknown. We used anA. fumigatusstrain lacking calcineurin A (cnaA), already shown to be critically important for pathogenicity, to evaluate galactomannan kinetics. During the logarithmic growth phase when glucose was consumed, β-D-galactofuranoside (galf)-antigens were released in the culture. However, after glucose became limited, GM release further increased in the supernatants of the wild type strain while there was no further increase of GM release in the ΔcnaAstrain. β-Galactofuranosidase activity was also decreased in the ΔcnaAmutant, and the amount of galf-antigen in the cell wall fraction of the ΔcnaAmutant was approximately ten-fold higher. This suggests the possibility that the antigen is unable to be released due to a cell wall abnormality. This and previous work suggest a dynamic calcineurin-dependent cell wall during periods of growth, with galactomannan release from the cell wall possibly calcineurin-dependent and reflected in the decreased GM release and greatly increased cell wall fraction of galfin the ΔcnaAmutant.