Department of Food and Bioproduct Sciences, College of Agriculture and Bioresources, University of Saskatchewan, 51 Campus Drive, Saskatoon, SK, S7N 5A8, Canada.
Appl Microbiol Biotechnol. 2013 Jan;97(1):417-28. doi: 10.1007/s00253-012-4386-4. Epub 2012 Oct 18.
Conversion of glycerol to 1,3-propanediol (1,3-PDO) is an attractive option to increase the economic efficiency of the biofuel industry. A bacterial strain that produced 1,3-PDO in the presence of glycerol was isolated from thin stillage, the fermentation residue of bioethanol production. This 1,3-PDO-producing organism was identified as Lactobacillus panis through biochemical characteristics and by 16S rRNA sequencing. Characterization of the L. panis strain hereafter designated as PM1 revealed it was an aerotolerant acidophilic anaerobe able to grow over a wide range of temperatures; tolerant to high concentrations of sodium chloride, ethanol, acetic acid, and lactic acid; and resistant to many common antibiotics. L. panis PM1 could utilize glucose, lactose, galactose, maltose, xylose, and arabinose, but could not grow on sucrose or fructose. Production of 1,3-PDO by L. panis PM1 occurred only when glucose was available as the carbon source in the absence of oxygen. These metabolic characteristics strongly suggested NADH recycling for glucose metabolism is achieved through 1,3-PDO production by this strain. These characteristics classified L. panis PM1 within the group III heterofermentative lactic acid bacteria, which includes the well-characterized 1,3-PDO-producing strain, Lactobacillus reuteri. Metabolite production profiles showed that L. panis PM1 produced considerable amounts of succinic acid (~11-12 mM) from normal MRS medium, which distinguishes this strain from L. reuteri strains.
将甘油转化为 1,3-丙二醇（1,3-PDO）是提高生物燃料行业经济效益的一种有吸引力的选择。从生物乙醇生产的发酵残余物稀薄酒糟中分离出了一种能在甘油存在下生产 1,3-PDO 的细菌菌株。通过生化特征和 16S rRNA 测序，该 1,3-PDO 生产菌被鉴定为乳杆菌属。这种 1,3-PDO 生产菌随后被命名为 PM1，它是一种耐氧嗜酸厌氧菌，能够在很宽的温度范围内生长；能够耐受高浓度的氯化钠、乙醇、乙酸和乳酸；并且对许多常见的抗生素具有抗性。L. panis PM1 可以利用葡萄糖、乳糖、半乳糖、麦芽糖、木糖和阿拉伯糖，但不能在蔗糖或果糖上生长。当葡萄糖作为碳源且不存在氧气时，L. panis PM1 才会产生 1,3-PDO。这些代谢特征强烈表明，该菌株通过 1,3-PDO 生产实现了 NADH 循环用于葡萄糖代谢。这些特征将 L. panis PM1 归类为 III 组异型发酵乳酸细菌，其中包括经过充分研究的 1,3-PDO 生产菌株乳杆菌属。代谢产物生产谱表明，L. panis PM1 从普通 MRS 培养基中产生了相当数量的琥珀酸（~11-12 mM），这使该菌株与乳杆菌属菌株区别开来。
