The synergistic action of accessory enzymes enhances the hydrolytic potential of a "cellulase mixture" but is highly substrate specific.
The synergistic action of accessory enzymes enhances the hydrolytic potential of a "cellulase mixture" but is highly substrate specific.
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DOI：
10.1186/1754-6834-6-112
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发表时间：
2013-08-03
影响因子：
6.3
通讯作者：
Saddler JN
中科院分区：
文献类型：
--
作者：
Hu J;Arantes V;Pribowo A;Saddler JN
目前，实现有效的纤维素水解所需的蛋白质/酶的量仍然太高。减少所需蛋白质/酶的量的一种方法是通过添加所谓的辅助酶如木聚糖酶、溶解性多糖单加氧酶（AA 9，以前称为GH 61）等来配制更有效的酶混合物，加入到纤维素酶混合物中。先前的工作已经表明，在蒸汽预处理的玉米秸秆的水解过程中，纤维素酶和木聚糖酶混合物之间可以发生强烈的协同作用，需要较低的蛋白质加载量来实现有效的水解。然而，需要相对较高的木聚糖酶载量。当家族10和11内切木聚糖酶和家族5木葡聚糖酶补充到商业纤维素酶混合物中时，观察到在一系列预处理的木质纤维素底物上不同程度的改善的水解。评估了纤维素酶单组分与来自家族10和11内切木聚糖酶（GH 10 EX和GH 11 EX）和家族5木葡聚糖酶（GH5 XG）的半纤维素酶在各种蒸汽预处理的木质纤维素底物的水解期间的潜在协同相互作用。添加辅助酶可明显提高纤维素酶单组分的水解活性，但这种“促进”作用具有高度的底物特异性。当单独添加时，GH 10 EX和GH5 XG都表现出广泛的底物特异性，并且显示出与纤维素酶的强协同相互作用。GH 10 EX对蒸汽预处理的农业残留物和硬木基质更有效，而GH5 XG添加对软木基质更有效。当一起添加时，GH 10 EX和GH5 XG之间的协同相互作用进一步增强了纤维素酶在一系列预处理的木质纤维素底物上的水解活性。当在水解速率已经稳定时加入到水解反应中时，GH 10 EX的加入还可以刺激进一步的纤维素水解。内切木聚糖酶和木葡聚糖酶与纤维素酶协同作用，以改善一系列预处理的木质纤维素底物的水解。然而，水解的改善程度是高度依赖于底物的。似乎具有更宽底物特异性的那些辅助酶，如GH 10 EX和GH5 XG，促进了纤维素酶混合物对所有预处理的生物质底物的水解性能的最大改善。
Currently, the amount of protein/enzyme required to achieve effective cellulose hydrolysis is still too high. One way to reduce the amount of protein/enzyme required is to formulate a more efficient enzyme cocktail by adding so-called accessory enzymes such as xylanase, lytic polysaccharide monooxygenase (AA9, formerly known as GH61), etc., to the cellulase mixture. Previous work has shown the strong synergism that can occur between cellulase and xylanase mixtures during the hydrolysis of steam pretreated corn stover, requiring lower protein loading to achieve effective hydrolysis. However, relatively high loadings of xylanases were required. When family 10 and 11 endo-xylanases and family 5 xyloglucanase were supplemented to a commercial cellulase mixture varying degrees of improved hydrolysis over a range of pretreated, lignocellulosic substrates were observed. The potential synergistic interactions between cellulase monocomponents and hemicellulases from family 10 and 11 endo-xylanases (GH10 EX and GH11 EX) and family 5 xyloglucanase (GH5 XG), during hydrolysis of various steam pretreated lignocellulosic substrates, were assessed. It was apparent that the hydrolytic activity of cellulase monocomponents was enhanced by the addition of accessory enzymes although the “boosting” effect was highly substrate specific. The GH10 EX and GH5 XG both exhibited broad substrate specificity and showed strong synergistic interaction with the cellulases when added individually. The GH10 EX was more effective on steam pretreated agriculture residues and hardwood substrates whereas GH5 XG addition was more effective on softwood substrates. The synergistic interaction between GH10 EX and GH5 XG when added together further enhanced the hydrolytic activity of the cellulase enzymes over a range of pretreated lignocellulosic substrates. GH10 EX addition could also stimulate further cellulose hydrolysis when added to the hydrolysis reactions when the rate of hydrolysis had levelled off. Endo-xylanases and xyloglucanases interacted synergistically with cellulases to improve the hydrolysis of a range of pretreated lignocellulosic substrates. However, the extent of improved hydrolysis was highly substrate dependent. It appears that those accessory enzymes, such as GH10 EX and GH5 XG, with broader substrate specificities promoted the greatest improvements in the hydrolytic performance of the cellulase mixture on all of the pretreated biomass substrates.
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影响因子：
6.1
作者：
Appeldoorn, Maaike M.;Kabel, Mirjam A.;Schols, Henk A.
通讯作者：
Schols, Henk A.
影响因子：
11.4
作者：
Banerjee, Goutami;Car, Suzana;Walton, Jonathan D.
通讯作者：
Walton, Jonathan D.
影响因子：
5.6
作者：
Kleywegt, GJ;Zou, JY;Jones, TA
通讯作者：
Jones, TA
影响因子：
2.1
作者：
LIN, LL;THOMSON, JA
通讯作者：
THOMSON, JA
影响因子：
4.1
作者：
Bonnin, Estelle;Daviet, Stephanie;Saulnier, Luc
通讯作者：
Saulnier, Luc