Many hydrogenotrophic methanogens use either H₂ or formate as the major electron donor to reduce CO₂ for methane production. The conventional cultivation of these organisms uses H₂ and CO₂ as the substrate with frequent replenishment of gas during growth. H₂ is explosive and requires an expensive gassing system to handle safely. Formate is as an ideal alternative substrate from the standpoints of both economy and safety but leads to large changes in the culture pH during growth. Here, we report that glycylglycine is an inexpensive and nontoxic buffer suitable for growth of Methanococcus maripaludis and Methanothermococcus okinawensis. This cultivation system is suitable for growth on liquid as well as solid medium in serum bottles. Moreover, it allows cultivation of liter scale cultures without expensive fermentation equipment. This formate cultivation system provides an inexpensive and flexible alternative for the growth of formate-utilizing, hydrogenotrophic methanogens.

中文翻译：

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一个灵活的系统，用于培养甲烷球菌和其他利用甲烷的产甲烷菌。

许多氢营养型产甲烷菌使用H ₂或甲酸盐作为主要的电子给体，以减少CO ₂以产生甲烷。这些生物的常规培养以H ₂和CO ₂为底物，在生长过程中经常补充气体。H ₂具有爆炸性，需要昂贵的充气系统才能安全处理。从经济性和安全性的角度来看，甲酸盐是理想的替代底物，但会导致生长过程中培养液pH值发生较大变化。在这里，我们报告说，甘氨酰甘氨酸是一种廉价且无毒的缓冲液，适合于马氏甲烷球菌和产甲烷球菌的生长。。该培养系统适合在液体和固体培养基中的血清瓶中生长。而且，它无需昂贵的发酵设备就可以培养公升规模的培养物。该甲酸盐培养系统为利用甲酸盐的氢营养型产甲烷菌的生长提供了廉价而灵活的替代方案。