CIIMAR/CIMAR-Laboratory of Ecotoxicology, Genomic and Evolution-Centre of Environmental and Marine Research, University of Porto, Rua dos Bragas 289, 4050-123 Porto, Portugal.
Mar Environ Res. 2012 Feb;73:7-16. doi: 10.1016/j.marenvres.2011.10.005. Epub 2011 Oct 31.
Cyanobacteria from estuarine habitats have been poorly studied regarding diversity and potential bioactive compounds production compared with their fresh and marine waters' congeners. In this work, 44 cyanobacteria isolates characterised from three Portuguese estuarine environments. Identification was performed based on diacritical morphological features of the isolates (e.g. cell shape, cell size, presence/absence of sheaths) and on 16S rRNA gene sequences phylogenetic analysis. Diversity of produced secondary metabolites was assessed by molecular and analytical tools. The isolates (mostly benthic forms) belonged to: (i) Chroococcales (Cyanobium, Synechocystis and Synechococcus), (ii) Oscillatoriales (Leptolyngbya, Microcoleus, Phormidium and Romeria) and (iii) Nostocales (Nostoc and Nodularia). 19 morphotypes were assigned at the species level, while phylogeny allowed us to distinguish 21 phylotypes spread amongst three distinct large clades. McyA and sxtI gene fragments were detected in some isolates, despite absence of toxins. Simultaneous presence of anabaenopeptins A and D was for the first time identified in Nostoc (LEGE06077). No correlation between morphological/phylogenetic relationships and the secondary-metabolite profile of the isolates was found. This is the first comprehensive study of estuarine cyanobacteria of Portuguese habitats revealing a diverse array of cyanobacteria that constitute an important source of potential bioactive compounds with ecological relevance and/or biomedical application.
与淡水和海洋水域的同类相比，河口生境中的蓝藻在多样性和潜在生物活性化合物生产方面的研究较少。在这项工作中，从三个葡萄牙河口环境中分离出了 44 株蓝藻。鉴定是基于分离物的形态特征（如细胞形状、细胞大小、有无鞘）和 16S rRNA 基因序列系统发育分析。通过分子和分析工具评估了次生代谢产物的多样性。这些分离物（主要是底栖形式）属于：（i）色球藻目（蓝藻、集胞藻和集球藻），（ii）颤藻目（颤藻、微鞘藻、普氏藻和罗梅里亚）和（iii）念珠藻目（念珠藻和鱼腥藻）。19 种形态型被分配到种水平，而系统发育使我们能够区分分布在三个不同大分支中的 21 个系统发育型。尽管没有毒素，但在一些分离物中检测到 McyA 和 sxtI 基因片段。鱼腥藻（LEGE06077）中首次同时鉴定出了 anabaenopeptins A 和 D。分离物的形态/系统发育关系与次生代谢产物谱之间没有相关性。这是对葡萄牙生境河口蓝藻的首次全面研究，揭示了一系列多样化的蓝藻，它们是具有生态相关性和/或医学应用的潜在生物活性化合物的重要来源。
