Mountfort D O, Roberton A M
J Gen Microbiol. 1978 Jun;106(2):353-60. doi: 10.1099/00221287-106-2-353.
Bacteriodes ruminicola grown on complex medium with glucose as carbon source gave acetate, CO2, formate and succinate as main fermentation products. No evidence was found for significant glucose catabolism by pathways other than the Embden-Meyerhof sequence. However, [U-14C]glucose fermentation gave products whose specific radioactivities were much lower than expected. There appear to be two main causes. Firstly, a rapid exchange occurred between metabolic intermediates and CO2, probably due to reversibility of the pathway between phosphoenolpyruvate and fumarate. Secondly, non-glucose precursors, mainly peptides and acetate, added to the medium as growth factors, also gave rise to the above end-products. The distortions that such reactions introduce into measurements of ATP molar growth yields based on product analyses and measurements of carbon flux based on radioactivity recovered in products are discussed.
以葡萄糖作为碳源在复合培养基上生长的反刍类拟杆菌产生乙酸盐、二氧化碳、甲酸盐和琥珀酸盐作为主要发酵产物。未发现除Embden-Meyerhof途径之外的其他途径对葡萄糖有显著的分解代谢。然而，[U-14C]葡萄糖发酵产生的产物，其比放射性远低于预期。这似乎有两个主要原因。首先，代谢中间产物与二氧化碳之间发生了快速交换，这可能是由于磷酸烯醇丙酮酸和富马酸之间途径的可逆性所致。其次，作为生长因子添加到培养基中的非葡萄糖前体，主要是肽和乙酸盐，也产生了上述终产物。讨论了此类反应在基于产物分析的ATP摩尔生长产率测量以及基于产物中回收放射性的碳通量测量中所引入的偏差。
