Department of Botany, School of Biology, Aristotle University of Thessaloniki, GR-541 24 Thessaloniki, Greece.
Department of Microbiology, University of Helsinki, Viikinkaari 9, FI-00014 Helsinki, Finland.
Mar Drugs. 2021 May 24;19(6):298. doi: 10.3390/md19060298.
Sponges form symbiotic relationships with diverse and abundant microbial communities. Cyanobacteria are among the most important members of the microbial communities that are associated with sponges. Here, we performed a genus-wide comparative genomic analysis of the newly described marine benthic cyanobacterial genus (Synechococcales). We obtained draft genomes from TAU-MAC 1615 and TAU-MAC 1115, isolated from marine sponges. We identified five additional genomes, host-associated or free-living, using a phylogenomic approach, and the comparison of all genomes showed that the sponge-associated strains display features of a symbiotic lifestyle. and have undergone genome reduction; they harbored considerably fewer genes encoding for (i) cofactors, vitamins, prosthetic groups, pigments, proteins, and amino acid biosynthesis; (ii) DNA repair; (iii) antioxidant enzymes; and (iv) biosynthesis of capsular and extracellular polysaccharides. They have also lost several genes related to chemotaxis and motility. Eukaryotic-like proteins, such as ankyrin repeats, playing important roles in sponge-symbiont interactions, were identified in sponge-associated genomes. The sponge-associated stains harbored biosynthetic gene clusters encoding novel natural products despite genome reduction. Comparisons of the biosynthetic capacities of with chemically rich cyanobacteria revealed that is another promising marine cyanobacterium for the biosynthesis of novel natural products.
海绵与多样且丰富的微生物群落形成共生关系。蓝细菌是与海绵相关的微生物群落中最重要的成员之一。在这里，我们对新描述的海洋底栖蓝细菌属 （螺旋藻目）进行了全属比较基因组分析。我们从海洋海绵中分离出的 TAU-MAC 1615 和 TAU-MAC 1115 获得了草图基因组。我们使用系统发育基因组学方法鉴定了另外五个宿主相关或自由生活的 基因组，对所有基因组的比较表明，与海绵相关的菌株显示出共生生活方式的特征。 和 经历了基因组缩减；它们编码的（i）辅因子、维生素、 prosthetic groups、色素、蛋白质和氨基酸生物合成；（ii）DNA 修复；（iii）抗氧化酶；（iv）荚膜和胞外多糖生物合成的基因数量显著减少。它们还失去了几个与趋化性和运动性相关的基因。在与海绵相关的 基因组中发现了真核样蛋白，如在海绵-共生体相互作用中起重要作用的锚蛋白重复序列。尽管基因组缩减，与海绵相关的 菌株仍具有编码新型天然产物的生物合成基因簇。与化学丰富的蓝细菌的生物合成能力比较表明， 是另一种有前途的海洋蓝细菌，可用于新型天然产物的生物合成。
