Presence of glycogen granules in anaerobic ammonium-oxidizing (anammox) bacteria has been reported so far. However, very little is known about their glycogen metabolism and the exact roles. Here, we studied the glycogen metabolism in “Ca. Brocadia sinica” growing in continuous retentostat cultures with bicarbonate as a carbon source. The effect of the culture growth phase was investigated. During the growing phase, intracellular glycogen content increased up to 32.6 mg-glucose (g-biomass dry wt)⁻¹ while the specific growth rate and ATP/ADP ratio decreased. The accumulated glycogen begun to decrease at the onset of entering the near-zero growth phase and was consumed rapidly when substrates were depleted. This clearly indicates that glycogen was synthesized and utilized as an energy storage. The proteomic analysis revealed that “Ca. B. sinica” synthesized glycogen via three known glycogen biosynthesis pathways and simultaneously degraded during the progress of active anammox, implying that glycogen is being continuously recycled. When cells were starved, a part of stored glycogen was converted to trehalose, a potential stress protectant. This suggests that glycogen serves at least as a primary carbon source of trehalose synthesis for survival. This study provides the first physiological evidence of glycogen metabolism in anammox bacteria and its significance in survival under natural substrate-limited habitat.

迄今为止，已经报道了在厌氧氨氧化（anammox）细菌中存在糖原颗粒。然而，人们对它们的糖原代谢和确切作用知之甚少。在这里，我们研究了“ Ca ”中的糖原代谢。Brocadia sinica”在以碳酸氢盐为碳源的连续滞留培养基中生长。研究了培养生长期的影响。在生长期，细胞内糖原含量增加到 32.6 mg-葡萄糖（g-生物质干重）^-1而比生长率和 ATP/ADP 比下降。积累的糖原在进入接近零的生长期开始时开始减少，并且在底物耗尽时迅速消耗。这清楚地表明糖原被合成并用作能量储存。蛋白质组学分析表明，“ Ca. B. sinica”通过三种已知的糖原生物合成途径合成糖原，并在活性厌氧氨氧化过程中同时降解，这意味着糖原正在不断地循环利用。当细胞饥饿时，一部分储存的糖原被转化为海藻糖，一种潜在的压力保护剂。这表明糖原至少作为海藻糖合成的主要碳源来生存。这项研究提供了厌氧氨氧化细菌糖原代谢的第一个生理学证据，及其在自然底物有限的栖息地生存的意义。