University of Lille, CNRS, UMR8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, Lille, France.
Institute of Microbiology, University of Lausanne and University Hospital Center, Lausanne, Switzerland.
Commun Biol. 2021 Mar 5;4(1):296. doi: 10.1038/s42003-021-01794-y.
The order Chlamydiales includes obligate intracellular pathogens capable of infecting mammals, fishes and amoeba. Unlike other intracellular bacteria for which intracellular adaptation led to the loss of glycogen metabolism pathway, all chlamydial families maintained the nucleotide-sugar dependent glycogen metabolism pathway i.e. the GlgC-pathway with the notable exception of both Criblamydiaceae and Waddliaceae families. Through detailed genome analysis and biochemical investigations, we have shown that genome rearrangement events have resulted in a defective GlgC-pathway and more importantly we have evidenced a distinct trehalose-dependent GlgE-pathway in both Criblamydiaceae and Waddliaceae families. Altogether, this study strongly indicates that the glycogen metabolism is retained in all Chlamydiales without exception, highlighting the pivotal function of storage polysaccharides, which has been underestimated to date. We propose that glycogen degradation is a mandatory process for fueling essential metabolic pathways that ensure the survival and virulence of extracellular forms i.e. elementary bodies of Chlamydiales.
该 Chlamydiales 订单包括能够感染哺乳动物，鱼类和变形虫的专性细胞内病原体。与其他细胞内细菌不同，细胞内适应导致糖元代谢途径的丧失，所有衣原体科都保持核苷酸依赖性糖元代谢途径，即 GlgC 途径，唯一的例外是 both Criblamydiaceae 和 Waddliaceae 科。通过详细的基因组分析和生化研究，我们已经表明，基因组重排事件导致了有缺陷的 GlgC 途径，更重要的是，我们在 both Criblamydiaceae 和 Waddliaceae 科中证明了独特的海藻糖依赖性 GlgE 途径。总之，这项研究强烈表明，糖原代谢在所有 Chlamydiales 中无一例外地保留下来，突出了储存多糖的关键作用，这一点迄今为止被低估了。我们提出糖原降解是为确保细胞外形式即衣原体的原体的生存和毒力的基本代谢途径提供燃料的强制性过程。
