Production of Useful Chemicals from Glycerol by Metabolic Modification of Microorganisms

为了从甘油中生产3-羟基丙酸（3-HP），我们使用了先前经过修饰的布拉基柠檬酸杆菌菌株TB-96-dLF，该菌株可以从甘油中生产高浓度的1,3-丙二醇（1,3- pd）。首先，我们破坏丙二醇脱氢酶（pdh）基因以阻断1,3- pd的产生（TB-96-dLFP）。由于TB-96-dLFP可能积累有毒的3-羟基丙醛（3-HPA）中间体，我们在好氧条件下发酵，通过3-HPA从甘油生产3-HP。然而，没有观察到3-HP的产生。这可能是由于甘油代谢的第一酶甘油脱水酶（Gdh）在有氧条件下的不稳定性。

To produce 3-hydroxypropionic acid (3-HP) from glycerol we used Citrobacter braakii strain TB-96-dLF, which was previously modified to produce high 1,3-propandiol (1,3-PD) concentration from glycerol. First, we disrupted propanediol dehydrogenase (pdh) gene to block 1,3-PD production (TB-96-dLFP). Since TB-96-dLFP may accumulate the toxic 3-hydroxypropionaldehyde (3-HPA) intermediate, we fermented it under aerobic condition as to produce 3-HP from glycerol via 3-HPA. However, no production of 3-HP was observed. This may be due to the instability of the first enzyme of glycerol metabolism which is glycerol dehydratase (Gdh) under aerobic conditions.