School of Chemical Engineering and Advanced Materials, Newcastle University, NE1 7RU, UK.
Bioresour Technol. 2013 Feb;130:552-8. doi: 10.1016/j.biortech.2012.12.064. Epub 2012 Dec 20.
The extracellular nuclease, NucB, from Bacillus licheniformis, can digest extracellular DNA in biofilms, causing biofilm dispersal, and may therefore be used commercially to remove biofilms. However, producing quantities of this secreted peptide is difficult and our aim was therefore to improve its laboratory scale production. This study builds on our understanding of B. licheniformis physiology to enhance NucB production. The addition of manganese, which triggers sporulation and enhances NucB expression, lead to a 5-fold increase in NucB production. Optimisation via Placket-Burman design of experiments identified 3 significant medium components and a subsequent Central Composite Design, to determine the optimum levels of these components, resulted in a 10-fold increase to 471U/ml. The optimal phosphate concentration was less than 0.3mM as this is known to inhibit nuclease production. The use of physiologically relevant information combined with optimisation represents a promising approach to increased enzyme production, which may also be widely applicable.
来自地衣芽孢杆菌的胞外核酸酶 NucB 可以消化生物膜中的胞外 DNA，导致生物膜分散，因此可能被商业用于去除生物膜。然而，大量生产这种分泌肽很困难，因此我们的目标是提高其实验室规模的生产。本研究基于我们对地衣芽孢杆菌生理学的理解来增强 NucB 的生产。添加锰，触发孢子形成并增强 NucB 的表达，导致 NucB 产量增加了 5 倍。通过 Placket-Burman 实验设计的优化确定了 3 种重要的培养基成分，随后进行的中心复合设计确定了这些成分的最佳水平，使产量增加了 10 倍，达到 471U/ml。最佳磷酸盐浓度小于 0.3mM，因为已知磷酸盐会抑制核酸酶的产生。使用生理相关信息结合优化是一种有前途的增加酶产量的方法，也可能具有广泛的适用性。
