Butanol is a promising biofuel with high energy intensity and can be used as gasoline substitute. It can be produced as a sustainable energy by microorganisms (such as Clostridia) from low-value biomass. However, th...Butanol is a promising biofuel with high energy intensity and can be used as gasoline substitute. It can be produced as a sustainable energy by microorganisms (such as Clostridia) from low-value biomass. However, the low productivity, yield and selectivity in butanol fermentation are still big challenges due to the lack of an efficient butanol-producing host strain. In this article, we systematically review the host cell engineering of Clostridia, focusing on (1) various strategies to rebalance metabolic flux to achieve a high butanol production by regulating the metabolism of carbon, redox or energy, (2) the challenges in pathway manipulation, and (3) the application of proteomics technology to understand the intracellular metabolism. In addition, the process engineer- ing is also briefly described. The objective of this review is to summarize the previous research achievements in the metabolic engineering of Clostridium and provide guidance for future novel strain construction to effectively produce butanol.展开更多
Spontaneous metastatic clostridial myonecrosis is a rare condition caused by Clostridium septicum.The underlying lesion is usually either a colonic neoplasm or leukemia.The authors reported a 67-year-old female who pr...Spontaneous metastatic clostridial myonecrosis is a rare condition caused by Clostridium septicum.The underlying lesion is usually either a colonic neoplasm or leukemia.The authors reported a 67-year-old female who presented with acute abdomen secondary to a perforated sigmoid cancer and who developed gas gangrene in her right leg.Unfortunately,despite all resuscitative measures,she died.The authors reviewed the literature;the diagnosis of metastatic myonecrosis was based on a high index of suspicion,development of bullae containing gram-positive rods,and subcutaneous crepitus(although this was a late sign).Treatment involves aggressive fluid replacement,high doses of intravenous penicillin,high concentration of oxygen,and surgical debridement,and/or amputation.The mortality remains very high,despite all the above measures.展开更多
文摘Butanol is a promising biofuel with high energy intensity and can be used as gasoline substitute. It can be produced as a sustainable energy by microorganisms (such as Clostridia) from low-value biomass. However, the low productivity, yield and selectivity in butanol fermentation are still big challenges due to the lack of an efficient butanol-producing host strain. In this article, we systematically review the host cell engineering of Clostridia, focusing on (1) various strategies to rebalance metabolic flux to achieve a high butanol production by regulating the metabolism of carbon, redox or energy, (2) the challenges in pathway manipulation, and (3) the application of proteomics technology to understand the intracellular metabolism. In addition, the process engineer- ing is also briefly described. The objective of this review is to summarize the previous research achievements in the metabolic engineering of Clostridium and provide guidance for future novel strain construction to effectively produce butanol.
文摘Spontaneous metastatic clostridial myonecrosis is a rare condition caused by Clostridium septicum.The underlying lesion is usually either a colonic neoplasm or leukemia.The authors reported a 67-year-old female who presented with acute abdomen secondary to a perforated sigmoid cancer and who developed gas gangrene in her right leg.Unfortunately,despite all resuscitative measures,she died.The authors reviewed the literature;the diagnosis of metastatic myonecrosis was based on a high index of suspicion,development of bullae containing gram-positive rods,and subcutaneous crepitus(although this was a late sign).Treatment involves aggressive fluid replacement,high doses of intravenous penicillin,high concentration of oxygen,and surgical debridement,and/or amputation.The mortality remains very high,despite all the above measures.