Over-expression in Escherichia coli of a thermally stable and regio-selective nitrile hydratase from Comamonas testosteroni 5-MGAM-4D
Over-expression in Escherichia coli of a thermally stable and regio-selective nitrile hydratase from Comamonas testosteroni 5-MGAM-4D
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DOI：
10.1007/s00253-004-1842-9
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发表时间：
2005-06-01
影响因子：
5
通讯作者：
Payne, MS
中科院分区：
文献类型：
--
作者：
Petrillo, KL;Wu, SJ;Payne, MS
克隆并测序了酮单胞菌5-MGAM-4D的耐热性和区域选择性的腈水合酶(NHase)和酰胺酶的基因，并在大肠杆菌中高效表达了活性NHase。最大的活性需要在NHaseβ亚基基因下游立即共表达一个小的开放阅读框。与天然生物体相比，大肠杆菌生物催化剂在干细胞重量的基础上具有近三倍的氨酶活性，而且这种活性明显更具热稳定性。此外，这种生物催化剂还能将多种丁腈底物转化为相应的酰胺类化合物。这种多功能性和坚固性是用于商业应用的生物催化剂的理想属性。
The genes encoding a thermally stable and regio-selective nitrile hydratase (NHase) and an amidase from Comamonas testosteroni 5-MGAM-4D have been cloned and sequenced, and active NHase has been over-produced in Escherichia coli. Maximal activity requires co-expression of a small open reading frame immediately downstream from the NHase beta subunit gene. Compared to the native organism, the E. coli biocatalyst has nearly threefold more NHase activity on a dry cell weight basis, and this activity is significantly more thermally stable. In addition, this biocatalyst converts a wide spectrum of nitrile substrates to the corresponding amides. Such versatility and robustness are desirable attributes of a biocatalyst intended for use in commercial applications.