期刊
MICROBIAL BIOTECHNOLOGY
卷 11, 期 3, 页码 486-497出版社
WILEY
DOI: 10.1111/1751-7915.13046
关键词
-
资金
- NWO-MoST Joint Program [2013DFG32630]
- National Basic Research Program (973 Program) [2013CB733600]
In a 54m(3) large-scale penicillin fermentor, the cells experience substrate gradient cycles at the timescales of global mixing time about 20-40s. Here, we used an intermittent feeding regime (IFR) and a two-compartment reactor (TCR) to mimic these substrate gradients at laboratory-scale continuous cultures. The IFR was applied to simulate substrate dynamics experienced by the cells at full scale at timescales of tens of seconds to minutes (30s, 3min and 6min), while the TCR was designed to simulate substrate gradients at an applied mean residence time (c) of 6min. A biological systems analysis of the response of an industrial high-yielding P.chrysogenum strain has been performed in these continuous cultures. Compared to an undisturbed continuous feeding regime in a single reactor, the penicillin productivity (q(PenG)) was reduced in all scale-down simulators. The dynamic metabolomics data indicated that in the IFRs, the cells accumulated high levels of the central metabolites during the feast phase to actively cope with external substrate deprivation during the famine phase. In contrast, in the TCR system, the storage pool (e.g. mannitol and arabitol) constituted a large contribution of carbon supply in the non-feed compartment. Further, transcript analysis revealed that all scale-down simulators gave different expression levels of the glucose/hexose transporter genes and the penicillin gene clusters. The results showed that q(PenG) did not correlate well with exposure to the substrate regimes (excess, limitation and starvation), but there was a clear inverse relation between q(PenG) and the intracellular glucose level.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据