以色列理工学院Debbie Lindell团队的研究显示，病毒NblA蛋白对海洋蓝藻光合作用有负面影响。2025年11月12日出版的《自然》杂志发表了这项成果。

利用最近开发的海洋噬藻体基因操作系统，研究组发现病毒NblA显著加速了噬藻体的感染周期，指导了宿主藻胆异构体和其他蛋白质的降解，降低了宿主光合作用的光收集效率。宏基因组分析显示，携带NblA的噬藻体在海洋中广泛存在，分别占海洋表层和深层光带T7样噬藻体的35%和65%。结果表明，NblA对噬藻体有很大的益处，而对宿主光合装置和宿主光合作用有负面影响。这些发现表明，噬藻体NblA对海洋微微蓝藻的光收集具有不利的全球影响。

研究人员表示，海洋微微蓝藻是全球重要的丰富的光合生物。它们在海洋中与感染蓝藻的噬藻病毒共存。噬蓝体携带许多从宿主获得的辅助代谢基因，这些基因被认为可以重新定向宿主的代谢，以使噬菌体受益。其中一个这样的基因是NblA，它存在于多个噬蓝细胞家族中。在营养剥夺的情况下，蓝藻NblA负责诱导藻胆异构体的蛋白水解降解，藻胆异构体是蓝藻的大型光合收光复合体。这增加了可用于基本任务的氨基酸库，作为一种生存机制。不同的噬蓝体NblA基因异位表达导致宿主色素蛋白降解。然而，病毒编码的NblA对噬蓝体的益处以及对宿主的更广泛影响尚不清楚。

附：英文原文

Title: Viral NblA proteins negatively affect oceanic cyanobacterial photosynthesis

Author: Nadel, Omer, Hanna, Rawad, Rozenberg, Andrey, Shitrit, Dror, Tahan, Ran, Pekarsky, Irena, Bj, Oded, Kleifeld, Oded, Lindell, Debbie

Issue&Volume: 2025-11-12

Abstract: Marine picocyanobacteria are abundant photosynthetic organisms of global importance. They coexist in the ocean with cyanophages—viruses that infect cyanobacteria. Cyanophages carry many auxiliary metabolic genes acquired from their hosts that are thought to redirect host metabolism for the phage’s benefit1,2,3,4,5. One such gene is nblA, which is present in multiple cyanophage families2,6,7,8. Under nutrient deprivation cyanobacterial NblA is responsible for inducing proteolytic degradation of the phycobilisome9,10,11, the large cyanobacterial photosynthetic light-harvesting complex. This increases the pool of amino acids available for essential tasks11, serving as a survival mechanism12. Ectopic expression of different cyanophage nblA genes results in host pigment protein degradation6,8,13. However, the benefit of the virus-encoded NblA for cyanophages and the broader impact on the host are unclear. Here, using a recently developed genetic manipulation system for marine cyanophages14, we reveal that viral NblA significantly accelerates the cyanophage infection cycle, directs degradation of the host phycobilisome and other proteins, and reduces host photosynthetic light-harvesting efficiency. Metagenomic analysis revealed that cyanophages carrying nblA are widespread in the oceans and comprise 35% and 65% of oceanic T7-like cyanophages in surface and deep photic zones, respectively. Our results show a large benefit of NblA to the cyanophage, while it exerts a negative effect on the host photosynthetic apparatus and host photosynthesis. These findings suggest that cyanophage NblA has an adverse global impact on light harvesting by oceanic picocyanobacteria.

DOI: 10.1038/s41586-025-09656-x

Source: https://www.nature.com/articles/s41586-025-09656-x