Anaerobic digestion was one of the first bioenergy strategies developed, yet the interactions of the microbial community that is responsible for the production of methane are still poorly understood. For example, it has only recently been recognized that the bacteria that oxidize organic waste components can forge electrical connections with methane-producing microbes through biologically produced, protein-based, conductive circuits. This direct interspecies electron transfer (DIET) is faster than interspecies electron exchange via diffusive electron carriers, such as H₂. DIET is also more resilient to perturbations such as increases in organic load inputs or toxic compounds. However, with current digester practices DIET rarely predominates. Improvements in anaerobic digestion associated with the addition of electrically conductive materials have been attributed to increased DIET, but experimental verification has been lacking. This deficiency may soon be overcome with improved understanding of the diversity of microbes capable of DIET, which is leading to molecular tools for determining the extent of DIET. Here we review the microbiology of DIET, suggest molecular strategies for monitoring DIET in anaerobic digesters, and propose approaches for re-engineering digester design and practices to encourage DIET.

厌氧消化是最早开发的生物能源策略之一，但对产生甲烷的微生物群落的相互作用仍然知之甚少。例如，直到最近人们才认识到，氧化有机废物成分的细菌可以通过生物产生的、基于蛋白质的导电电路与产生甲烷的微生物建立电连接。这种直接的种间电子转移（DIET）比通过扩散电子载体（例如H _{2 ）}进行的种间电子交换更快。饮食对有机负荷输入或有毒化合物增加等扰动也更具弹性。然而，在目前的沼气池实践中，饮食很少占主导地位。与添加导电材料相关的厌氧消化的改善归因于饮食的增加，但缺乏实验验证。随着对具有 DIET 能力的微生物多样性的进一步了解，这一缺陷可能很快就会被克服，从而产生用于确定 DIET 程度的分子工具。在这里，我们回顾了饮食的微生物学，提出了监测厌氧消化池中饮食的分子策略，并提出了重新设计消化池设计和实践以鼓励饮食的方法。