Jiangsu Provincial Key Laboratory of New Drug Research and Clinical Pharmacy, School of Pharmacy, Xuzhou Medical University, Xuzhou, 221000, Jiangsu Province, China; Department of Pharmaceutical Analysis, School of Pharmacy, Xuzhou Medical University, Xuzhou, 221000, Jiangsu Province, China.
Jiangsu Provincial Key Laboratory of New Drug Research and Clinical Pharmacy, School of Pharmacy, Xuzhou Medical University, Xuzhou, 221000, Jiangsu Province, China; Department of Bioinformatics, School of Medical Informatics and Engineering, Xuzhou Medical University, Xuzhou, 221000, Jiangsu Province, China.
Carbohydr Polym. 2021 May 1;259:117773. doi: 10.1016/j.carbpol.2021.117773. Epub 2021 Feb 8.
Diurnal alteration of glycogen molecular structure has been identified in healthy mice. Recently, both fragile (disintegration in dimethyl sulfoxide) and stable (not disintegrating in DMSO) glycogen particles were found in Escherichia coli. However, how glycogen structure changes dynamically in E. coli is not clear. The question examined here is whether fragile, stable glycogen α particles occur in bacteria, following a similar pattern as in mice. In this study, we examine the dynamic changes of glycogen molecular structure over 24-h in E. coli BL21(DE3), using transmission electron microscopy, size exclusion chromatography and fluorophore-assisted carbohydrate electrophoresis at representative time points. It was found that glycogen structure was mainly fragile at the synthesis stage and largely stable during the degradation stage. qRT-PCR results indicated that balance of anabolic and catabolic gene expression levels in glycogen metabolism could be a key factor affecting the fragility of glycogen α particles in bacteria.
健康小鼠的糖原分子结构具有昼夜变化。最近，在大肠杆菌中发现了不稳定（在二甲基亚砜中解体）和稳定（在 DMSO 中不解体）的糖原颗粒。然而，糖原结构在大肠杆菌中如何动态变化尚不清楚。这里要研究的问题是，在细菌中是否存在类似于小鼠的脆性、稳定的糖原α颗粒。在这项研究中，我们使用透射电子显微镜、排阻色谱和荧光标记碳水化合物电泳，在代表性时间点，研究了大肠杆菌 BL21(DE3)中糖原分子结构在 24 小时内的动态变化。结果发现，糖原结构在合成阶段主要是脆弱的，而在降解阶段则主要是稳定的。qRT-PCR 结果表明，糖原代谢中合成代谢和分解代谢基因表达水平的平衡可能是影响细菌中糖原α颗粒脆性的关键因素。
