Department of Biochemistry and Cell Physiology, Voronezh State University, 1 Universitetskaya pl, Voronezh, 394018, Russia.
Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, 119071, Moscow, Russia.
Arch Microbiol. 2021 May;203(4):1595-1599. doi: 10.1007/s00203-020-02158-6. Epub 2021 Jan 5.
Filamentous iron oxides accumulating bacteria Sphaerotilus natans subsp. natans and S. natans subsp. sulfidivorans were described as subspecies based on 99.7% identity of their 16S rRNA sequences, in spite of important physiological difference. The ANI between their genomes was 94.7%, which indicate their assignment to different species. S. natans subsp. sulfidivorans and S. montanus possess genes for a complete SOX system, while S. natans subsp. natans encode only SoxYZ. There are genes for the Calvin cycle in the genomes of S. hippei DSM 566, S. natans subsp. sulfidivorans D-501, and S. montanus HS. Lithoautotrophy on reduced sulfur compounds is probably possible for S. natans subsp. sulfidivorans and S. montanus, but not for S. natans subsp. natans. Considering significant differences in the genome characteristics and metabolic potential of S. natans subsp. sulfidivorans and S. natans subsp. natans, we propose their classification as different species, S. natans and S. sulfidivorans sp. nov.
聚球藻铁氧化菌（Sphaerotilus natans subsp. natans）和聚球藻铁氧化菌（S. natans subsp. sulfidivorans）亚种是根据其 16S rRNA 序列 99.7%的同一性来描述的，尽管它们在生理上有很大的不同。它们的基因组之间的 ANI 为 94.7%，这表明它们属于不同的种。聚球藻铁氧化菌（S. natans subsp. sulfidivorans）和聚球藻铁氧化菌（S. montanus）拥有完整的 SOX 系统基因，而聚球藻铁氧化菌（S. natans subsp. natans）只编码 SoxYZ。海鞘藻（S. hippei DSM 566）、聚球藻铁氧化菌（S. natans subsp. sulfidivorans D-501）和 S. montanus HS 的基因组中都有卡尔文循环的基因。聚球藻铁氧化菌（S. natans subsp. sulfidivorans）和 S. montanus 可能能够利用还原态硫化合物进行自养生活，但聚球藻铁氧化菌（S. natans subsp. natans）则不行。考虑到聚球藻铁氧化菌（S. natans subsp. sulfidivorans）和聚球藻铁氧化菌（S. natans subsp. natans）在基因组特征和代谢潜力方面存在显著差异，我们建议将它们分类为不同的种，即聚球藻（S. natans）和硫氧化聚球藻（S. sulfidivorans sp. nov.）。
