Center for Nuclear Energy in Agriculture, University of São Paulo, Avenida Centenário 303, Piracicaba, 13400-970 São Paulo, Brazil.
Department of Microbiology, University of Helsinki, Viikinkaari 9, FI-00014 Helsinki, Finland.
Toxins (Basel). 2020 Feb 25;12(3):141. doi: 10.3390/toxins12030141.
The bloom-forming cyanobacterium CENA596 encodes the biosynthetic gene clusters (BGCs) of the known natural products nodularins, spumigins, anabaenopeptins/namalides, aeruginosins, mycosporin-like amino acids, and scytonemin, along with the terpenoid geosmin. Targeted metabolomics confirmed the production of these metabolic compounds, except for the alkaloid scytonemin. Genome mining of CENA596 and its three closely related strains-two planktonic strains from the Baltic Sea and one benthic strain from Japanese marine sediment-revealed that the number of BGCs in planktonic strains was higher than in benthic one. Geosmin-a volatile compound with unpleasant taste and odor-was unique to the Brazilian strain CENA596. Automatic annotation of the genomes using subsystems technology revealed a related number of coding sequences and functional roles. Orthologs from the genomes are involved in the primary and secondary metabolisms. Phylogenomic analysis of CENA596 based on 120 conserved protein sequences positioned this strain close to the Baltic . Phylogeny of the 16S rRNA genes separated the Brazilian CENA596 strain from those of the Baltic Sea, despite their high sequence identities (99% identity, 100% coverage). The comparative analysis among planktic strains showed that their genomes were considerably similar despite their geographically distant origin.
形成水华的蓝藻 CENA596 编码已知天然产物 nodularin、spumigin、anabaenopeptins/namalides、aeruginosins、mycosporin-like amino acids 和 scytonemin 以及萜烯类物质 geosmin 的生物合成基因簇 (BGCs)。靶向代谢组学证实了这些代谢化合物的产生,除了生物碱 scytonemin 外。对 CENA596 及其三个密切相关菌株(波罗的海的两个浮游菌株和日本海洋沉积物的一个底栖菌株)的基因组挖掘显示,浮游菌株中的 BGCs 数量高于底栖菌株。Geosmin-一种具有不愉快味道和气味的挥发性化合物-是巴西菌株 CENA596 所特有的。使用子系统技术对基因组进行自动注释揭示了数量相当的编码序列和功能角色。基因组的同源物参与初级和次级代谢。基于 120 个保守蛋白质序列的 CENA596 系统发育分析将该菌株定位在波罗的海附近。尽管 16S rRNA 基因的系统发育将巴西的 CENA596 菌株与波罗的海的菌株分开,但它们的序列高度相似(99%的同一性,100%的覆盖率)。浮游菌株之间的比较分析表明,尽管它们的起源地理位置遥远,但它们的基因组非常相似。