DataSheet2_The survivor strain: isolation and characterization of Phormidium yuhuli AB48, a filamentous phototactic cyanobacterium with biotechnological potential.docx

Despite their recognized potential, current applications of cyanobacteria as microbial cell factories remain in early stages of development. This is partly due to the fact that engineered strains are often difficult to grow at scale. This technical challenge contrasts with the dense and highly productive cyanobacteria populations thriving in many natural environments. It has been proposed that the selection of strains pre-adapted for growth in industrial photobioreactors could enable more productive cultivation outcomes. Here, we described the initial morphological, physiological, and genomic characterization of Phormidium yuhuli AB48 isolated from an industrial photobioreactor environment. P. yuhuli AB48 is a filamentous phototactic cyanobacterium with a growth rate comparable to Synechocystis sp. PCC 6803. The isolate forms dense biofilms under high salinity and alkaline conditions and manifests a similar nutrient profile to Arthrospira platensis (Spirulina). We sequenced, assembled, and analyzed the P. yuhuli AB48 genome, the first closed circular isolate reference genome for a member of the Phormidium genus. We then used cultivation experiments in combination with proteomics and metabolomics to investigate growth characteristics and phenotypes related to industrial scale cultivation, including nitrogen and carbon utilization, salinity, and pH acclimation, as well as antibiotic resistance. These analyses provide insight into the biological mechanisms behind the desirable growth properties manifested by P. yuhuli AB48 and position it as a promising microbial cell factory for industrial-scale bioproduction[221, 1631].

尽管蓝细菌（cyanobacteria）作为微生物细胞工厂（microbial cell factories）的应用潜力已得到广泛认可，但目前其相关应用仍处于早期研发阶段。这一现状部分源于工程菌株往往难以实现规模化培养。这一技术难题，与自然环境中大量存在且生产力极高的蓝细菌种群形成鲜明对比。有研究提出，筛选预先适应工业光生物反应器（photobioreactor）生长环境的菌株，有望实现更高效的规模化培养。本研究对一株分离自工业光生物反应器环境的尤利颤丝藻AB48（Phormidium yuhuli AB48）进行了初步的形态学、生理学及基因组学表征。该菌株为丝状趋光性蓝细菌，生长速率与集胞藻PCC 6803（Synechocystis sp. PCC 6803）相当。其在高盐、碱性条件下可形成致密的生物被膜，营养特征与钝顶节旋藻（螺旋藻，Arthrospira platensis (Spirulina)）相似。我们完成了尤利颤丝藻AB48的全基因组测序、组装与分析，这是颤丝藻属（Phormidium）首个闭合环状分离参考基因组。随后结合培养实验与蛋白质组学（proteomics）、代谢组学（metabolomics）分析，探究了该菌株与工业规模化培养相关的生长特性与表型，包括氮碳利用、盐度与pH适应性，以及抗生素抗性。这些分析揭示了尤利颤丝藻AB48所具备的优良生长特性背后的生物学机制，使其成为工业规模生物生产领域极具潜力的微生物细胞工厂[221, 1631]。