The roles of the zinc finger transcription factors XlnR, ClrA and ClrB in the breakdown of lignocellulose by Aspergillus niger.
The roles of the zinc finger transcription factors XlnR, ClrA and ClrB in the breakdown of lignocellulose by Aspergillus niger.
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DOI：
10.1186/s13568-016-0177-0
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发表时间：
2016-03
期刊：
影响因子：
3.7
通讯作者：
Archer DB
中科院分区：
文献类型：
--
作者：
Raulo R;Kokolski M;Archer DB
从黑曲霉中删除编码关键转录因子（TF） XlnR、ClrA和ClrB的基因，并对得到的菌株在葡萄糖和麦秸上的生长、糖基水解酶编码基因的转录和糖化活性进行了评估。在秸秆中测定pH值和葡萄糖胺含量，所有突变株的生长都比野生型（WT）菌株受到损害，尽管clrA的缺失比xlnR或clrB的缺失影响要小。与WT培养滤液相比，TF缺失菌株的培养滤液也降低了麦秸中糖的释放量。在有和无pH控制的条件下，测定了所有菌株在葡萄糖和麦秸培养基中分批培养时cbhA、eglC和xynA的转录水平。与WT相比，所有突变株的cbhA和eglC转录物水平都降低了，尽管删除clrA对eglC表达的影响不明显，对xynA也没有影响。对转录的影响与ph的变化无关。除了在麦秸上生长受损外，ΔxlnR菌株对氧化应激敏感，在葡萄糖条件下表现出细胞壁缺陷，这表明XlnR有其他作用。诸如ClrB等tf的特性为生产第二代生物燃料的工业过程提供了新的改进领域。本文的在线版本（doi:10.1186/s13568-016-0177-0）包含补充材料，可供授权用户使用。
Genes encoding the key transcription factors (TF) XlnR, ClrA and ClrB were deleted from Aspergillus niger and the resulting strains were assessed for growth on glucose and wheat straw, transcription of genes encoding glycosyl hydrolases and saccharification activity. Growth of all mutant strains, based in straw on measurement of pH and assay of glucosamine, was impaired in relation to the wild-type (WT) strain although deletion of clrA had less effect than deletion of xlnR or clrB. Release of sugars from wheat straw was also lowered when culture filtrates from TF deletion strains were compared with WT culture filtrates. Transcript levels of cbhA, eglC and xynA were measured in all strains in glucose and wheat straw media in batch culture with and without pH control. Transcript levels from cbhA and eglC were lowered in all mutant strains compared to WT although the impact of deleting clrA was not pronounced with expression of eglC and had no effect on xynA. The impact on transcription was not related to changes in pH. In addition to impaired growth on wheat straw, the ΔxlnR strain was sensitive to oxidative stress and displayed cell wall defects in the glucose condition suggesting additional roles for XlnR. The characterisation of TFs, such as ClrB, provides new areas of improvement for industrial processes for production of second generation biofuels. The online version of this article (doi:10.1186/s13568-016-0177-0) contains supplementary material, which is available to authorized users.