Oceanic cyanobacteria are the most abundant oxygen-generating phototrophs on our planet and are therefore important to life. These organisms are infected by viruses called cyanophages, which have recently shown to encode metabolic genes that modulate host photosynthesis, phosphorus cycling and nucleotide metabolism. Herein we report the characterization of a wild-type flavin-dependent viral halogenase (VirX1) from a cyanophage. Notably, halogenases have been previously associated with secondary metabolism, tailoring natural products. Exploration of this viral halogenase reveals it capable of regioselective halogenation of a diverse range of substrates with a preference for forming aryl iodide species; this has potential implications for the metabolism of the infected host. Until recently, a flavin-dependent halogenase that is capable of iodination in vitro had not been reported. VirX1 is interesting from a biocatalytic perspective as it shows strikingly broad substrate flexibility and a clear preference for iodination, as illustrated by kinetic analysis. These factors together render it an attractive tool for synthesis.

海洋蓝藻是地球上最丰富的产氧光养生物，因此对生命很重要。这些生物体被称为噬藻体的病毒感染，最近显示这些病毒编码调节宿主光合作用、磷循环和核苷酸代谢的代谢基因。在这里，我们报告了来自噬藻体的野生型黄素依赖性病毒卤化酶 (VirX1) 的表征。值得注意的是，卤化酶以前与二次代谢有关，可以定制天然产物。对这种病毒卤化酶的探索表明，它能够对多种底物进行区域选择性卤化，并优先形成芳基碘化物；这对受感染宿主的新陈代谢有潜在的影响。直到最近，尚未报道能够在体外碘化的黄素依赖性卤化酶。从生物催化的角度来看，VirX1 很有趣，因为它显示出惊人的广泛底物灵活性和对碘化的明显偏好，如动力学分析所示。这些因素共同使它成为一种有吸引力的综合工具。