Jiang Ling, Cai Jin, Wang Jufang, Liang Shizhong, Xu Zhinan, Yang Shang-Tian
School of Bioscience and Bioengineering, South China University of Technology, Guangzhou 510006, PR China.
Bioresour Technol. 2010 Jan;101(1):304-9. doi: 10.1016/j.biortech.2009.08.024. Epub 2009 Sep 1.
The uptake and metabolism of sucrose, the major sugar in industrial cane molasses, by Clostridium tyrobutyricum ZJU 8235 was investigated and this study provided the first definitive evidence for phosphoenolpyruvate (PEP)-dependent phosphotransferase system (PTS) activity in butyric acid-producing bacteria. Glucose was utilized preferentially to sucrose when both substrates were present in the medium. The PEP-dependent sucrose: PTS was induced by growing C. tyrobutyricum on sucrose (but not glucose) as the sole carbon source. Extract fractionation and PTS reconstitution experiments revealed that both soluble and membrane components were required for bioactivity. Sucrose-6-phosphate hydrolase and fructokinase activities were also detected in sucrose-grown cultures. Based on these findings, a pathway of sucrose metabolism in this organism was proposed that includes the forming of sucrose-6-phosphate via the PTS and its further degradation into glucose-6-phosphate and fructose-6-phosphate.
研究了酪丁酸梭菌ZJU 8235对工业甘蔗糖蜜中的主要糖类蔗糖的摄取和代谢情况，该研究首次明确证明了产丁酸细菌中存在磷酸烯醇式丙酮酸（PEP）依赖性磷酸转移酶系统（PTS）活性。当培养基中同时存在葡萄糖和蔗糖这两种底物时，葡萄糖比蔗糖更优先被利用。通过以蔗糖（而非葡萄糖）作为唯一碳源培养酪丁酸梭菌，可诱导出PEP依赖性蔗糖：PTS。提取物分级分离和PTS重组实验表明，生物活性需要可溶性成分和膜成分二者共同存在。在以蔗糖培养的培养物中还检测到了蔗糖-6-磷酸水解酶和果糖激酶活性。基于这些发现，提出了该生物体中蔗糖代谢的一条途径，包括通过PTS形成蔗糖-6-磷酸及其进一步降解为葡萄糖-6-磷酸和果糖-6-磷酸。
