FNU Prof. Ouyang Songying’s Team Make New Progress in the Study of Immune Mechanism of Bacterial Infection


Recently, Prof. Ouyang Songyings team of FNU, in collaboration with Prof. Long Feng of Wuhan University (WHU) and Prof. Li Jinyu of Fuzhou University (FZU), have revealed the mechanism of how SPARSA recognizes exogenous nucleic acids and exerts its anti-phage role using the cryo-electron microscopy (cryo-EM), together with biochemical and molecular dynamics simulations. The results, titled “Structural basis of antiphage immunity generated by a prokaryotic Argonaute-associated SPARSA system, were published in Nature Communication. FNU is the first affiliation of the paper, with Prof. Ouyang Songying, Prof. Feng Long of WHU and Prof. Jinyu Li of FZU as the co-corresponding authors; Zhen Xiangkai, Associate Researcher of College of Life Sciences of FNU, Ye Le and Huang Zhijie, both master students of FNU, Xu Xiaolong, a doctoral student of WHU, and Xie Song, a master student of FZU, are the co-first authors of the paper. The work was supported by the National Natural Science Foundation of China and the National Key Research and Development Program of China.

It is reported that in the evolutionary arms race between pathogenic microorganisms and viruses (phages), bacteria have evolved a myriad of immune systems against exogenous viruses and that the study of microbial defense systems will provide not only new ideas for the prevention and treatment of drug-resistant microorganisms, but also guidance for the discovery of immune molecules related to higher organisms and their functional studies. Argonaute (Ago) is found in both eukaryotes and prokaryotes. Recent studies have revealed that like eukaryotic Agos (eAgos), prokaryotic Agos (pAgos) also serve as antiviral systems. In the SPARSA system, after sensing exogenous viruses, Ago activates a neighboring effector protein with nicotinamide adenine dinucleotide (NAD+), and induces bacterial death through the degradation of NAD+, thus removing infected viruses and exerting its antiviral functions. The results reveal a novel immunoregulatory mechanism and contribute to the development of tools for virus detection.

Link to the paper: https://doi.org/10.1038/s41467-023-44660-7


(Translated by Cai Yuan/ Reviewed by Xie Xiujuan)