高产聚-β-羟基丁酸酯的甲烷氧化菌OB3b和光合菌共培养体系驯化

Domestication of high-yield poly-β-hydroxybutyrate co-culture system of Methylosinus trichosporium OB3b and photosynthetic bacteria

中文关键词:  聚-β-羟基丁酸酯  甲烷氧化菌OB3b  光合菌  丰盛-饥饿模式  驯化

英文关键词:poly-β-hydroxybutyrate  Methylosinus trichosporium OB3b  photosynthetic bacteria  feast-famine mode  acclimation

中文摘要:

      目的 提高甲烷氧化菌OB3b (Methylosinus trichosporium OB3b)和光合菌共培养体系中聚-β-羟基丁酸酯(poly-β-hydroxybutyrate, PHB)的产量。方法 采用丰盛-饥饿间歇供料法对共生菌进行好氧开放式培养, 以生长速度、PHB产量、特征性酶甲烷单加氧酶活性为主要指标, 考察驯化过程中共培养体系PHB产量及甲烷氧化菌活性的变化。结果 经过4轮的丰盛-饥饿间歇供料驯化, 丰盛期细胞密度可达1.2以上, 饥饿期细胞密度下降速度显著降低, 细胞存活率高, 驯化作用明显, 菌体内PHB含量从11.76%增加到37.34% (w/w), 传代稳定性良好。结论 通过丰盛-饥饿间歇供料模式驯化后的共培养体系PHB产量明显提高, 得到了稳定的高产PHB甲烷氧化菌-光合菌共培养体系。

英文摘要:

      Objective To increase the yield of poly-β-hydroxybutyrate (PHB) in the co-culture system of methanotroph (Methylosinus trichosporium OB3b) and photosynthetic bacteria. Methods The aerobic open culture of symbiotic bacteria was carried out by the intermittent feeding feast-famine mode method. The growth rate, PHB yield and characteristic enzyme methane monooxygenase activity were taken as the main indexes to investigate the changes of PHB yield and methanotroph activity in the co-culture system during acclimation. Results After 4 rounds of enrichment-starvation intermittent feeding feast-famine acclimation, the cell density in the feeding feast period could reach more than 1.2, decline rates of cell density decreased significantly during famine, the cell survival rate was high, and the acclimation effect was obvious. The PHB content in the bacteria increased from 11.76% to 37.34% (w/w), and the passage stability was good. Conclusion The PHB yield of the co-culture system acclimated by intermittent feeding feast-famine mode is significantly improved, and a stable high-yield PHB methane oxidizing bacteria-photosynthetic bacteria co-culture system is obtained.