Wang Fangzhong, Wang Mingyu, Zhao Qi, Niu Kangle, Liu Shasha, He Didi, Liu Yan, Xu Shiping, Fang Xu
State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China.
Center for Biosafety Research and Strategy, Tianjin University, Tianjin, China.
Front Microbiol. 2019 Sep 10;10:2035. doi: 10.3389/fmicb.2019.02035. eCollection 2019.
Characterizing and engineering microbial communities for lignocellulosic biofuel production has received widespread attention. Previous research has established that JN4 and GD17 coculture significantly improves overall cellulosic biofuel production efficiency. Here, we investigated this interaction and revealed the mechanism underlying the improved efficiency observed. In contrast to the previously reported mutualistic relationship, a harmful effect toward . JN4 was observed in these microbial consortia. Although GD17 relieves the carbon catabolite repression of . JN4 regarding obtaining more cellobiose or glucose released from lignocellulose, GD17 significantly hampers the growth of . JN4 in coculture. The increased formation of end products is due to the strong competitive metabolic advantage of GD17 over . JN4 in the conversion of glucose or cellobiose into final products. The possibility of controlling and rebalancing these microbial consortia to modulate cellulose degradation was achieved by adding GD17 stimulants into the system. As cellulolytic bacteria are usually at a metabolic disadvantage, these discoveries may apply to a large proportion of cellulosic biofuel-producing microbial consortia. These findings provide a reference for engineering efficient and modular microbial consortia for modulating cellulosic conversion.
对用于木质纤维素生物燃料生产的微生物群落进行表征和工程改造已受到广泛关注。先前的研究表明，JN4和GD17共培养可显著提高纤维素生物燃料的整体生产效率。在此，我们研究了这种相互作用，并揭示了观察到的效率提高背后的机制。与先前报道的互利关系相反，在这些微生物群落中观察到了对JN4的有害影响。尽管GD17在获取从木质纤维素释放的更多纤维二糖或葡萄糖方面减轻了JN4的碳分解代谢物阻遏，但GD17在共培养中显著阻碍了JN4的生长。终产物形成的增加是由于GD17在将葡萄糖或纤维二糖转化为终产物方面相对于JN4具有强大的竞争性代谢优势。通过向系统中添加GD17刺激物，实现了控制和重新平衡这些微生物群落以调节纤维素降解的可能性。由于纤维素分解细菌通常处于代谢劣势，这些发现可能适用于很大一部分生产纤维素生物燃料的微生物群落。这些发现为构建高效且模块化的微生物群落以调节纤维素转化提供了参考。
