Systems-level flux analysis of Clostridium phytofermentans for metabolically engineered optimal production of biofuels

Abstract

Catabolite repression is a significant impediment to industrial scale generation of biofuels using microbial metabolism of plant biomass. In order to overcome this limitation, we aim to generate a bacterial co-culture composed of a number of engineered organisms that have the capability to consume only select sugars. The base organism for our effort is Clostridium phytofermentans (Cphy), a gene5cally tractable model bacterium that can directly convert a broad range of biomass sources into ethanol and hydrogen gas. One of the most attractive characteristics of this organism is that Cphy can produce biofuels without the need for expensive thermochemical pretreatment and enzyme additions. Here we report the latest results of our engineering effort. Better understanding of Cphy can provide bioengineering solutions to simultaneously utilize all forms of pentose and hexose sugars present in the plant waste. Using our genome-scale flux balance analysis (FBA) model of metabolism in Cphy, constrained by our experimental data, we search for solution for optimal degradation of plant material, and production of biofuels in Cphy.

Full text

Systems-level*flux*analysis*of*Clostridium+phytofermentans*for*
metabolically*engineered*op9mal*produc9on*of*biofuels*
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System-level*Analysis*of*Cphy*metabolism*
Abstract*
References:*
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Time (hours)
mM Metabolite
Cellobiose + Xylose H Column
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Time (hours)
mM Metabolite
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Time (hours)
mM Metabolite
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Time (hours)
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Time (hours)
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Xylose H Column
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Time (hours)
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Time (hours)
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Time (hours)
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