Departamento de Biología, Darwin, 2, Universidad Autónoma de Madrid, 28049 Madrid, Spain; College of Marine and Environmental Sciences, James Cook University, Townsville 4811, QLD, Australia.
Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, 0349 Oslo, Norway.
Harmful Algae. 2016 Apr;54:21-43. doi: 10.1016/j.hal.2015.09.007.
The traditional genus Aphanizomenon comprises a group of filamentous nitrogen-fixing cyanobacteria of which several memebers are able to develop blooms and to produce toxic metabolites (cyanotoxins), including hepatotoxins (microcystins), neurotoxins (anatoxins and saxitoxins) and cytotoxins (cylindrospermopsin). This genus, representing geographically widespread and extensively studied cyanobacteria, is in fact heterogeneous and composed of at least five phylogenetically distant groups (Aphanizomenon, Anabaena/Aphanizomenon like cluster A, Cuspidothrix, Sphaerospermopsis and Chrysosporum) whose taxonomy is still under revision. This review provides a thorough insight into the phylogeny, ecology, biogeography and toxicogenomics (cyr, sxt, and ana genes) of the five best documented "Aphanizomenon" species with special relevance for water risk assessment: Aphanizomenon flos-aquae, Aphanizomenon gracile, Cuspidothrix issatschenkoi, Sphaerospermopsis aphanizomenoides and Chrysosporum ovalisporum. Aph. flos-aquae, Aph. gracile and C. issatschenkoi have been reported from temperate areas only whereas S. aphanizomenoides shows the widest distribution from the tropics to temperate areas. Ch. ovalisporum is found in tropical, subtropical and Mediterranean areas. While all five species show moderate growth rates (0.1-0.4day) within a wide range of temperatures (15-30°C), Aph. gracile and A. flos-aquae can grow from around (or below) 10°C, whereas Ch. ovalisporum and S. aphanizomenoides are much better competitors at high temperatures over 30°C or even close to 35°C. A. gracile has been confirmed as the producer of saxitoxins and cylindrospermopsin, C. issatschenkoi of anatoxins and saxitoxins and Ch. ovalisporum of cylindrospermopsin. The suspected cylindrospermopsin or anatoxin-a production of A. flos-aquae or microcystin production of S. aphanizomenoides is still uncertain. This review includes a critical discussion on the the reliability of toxicity reports and on the invasive potential of "Aphanizomenon" species in a climate change scenario, together with derived knowledge gaps and research needs. As a whole, this work is intended to represent a key reference for scientists and water managers involved in the major challenges of identifying, preventing and mitigating toxic Aphanizomenon blooms.
传统的节旋藻属包括一组丝状固氮蓝藻，其中一些成员能够形成水华，并产生有毒的代谢物（蓝藻毒素），包括肝毒素（微囊藻毒素）、神经毒素（anatoxins 和 saxitoxins）和细胞毒素（cylindrospermopsin）。该属代表了地理分布广泛且广泛研究的蓝藻，实际上是异质的，由至少五个在系统发育上相距甚远的群体（节旋藻属、鱼腥藻属/节旋藻属样簇 A、Cuspidothrix、Sphaerospermopsis 和 Chrysosporum）组成，其分类仍在修订中。本综述深入探讨了具有特殊水风险评估意义的五种记录最完善的“节旋藻属”物种的系统发育、生态学、生物地理学和毒发生物学（cyr、sxt 和 ana 基因）：水华束丝藻、纤细节旋藻、Issatschenkia 角丝藻、球形颤藻和卵形棕囊藻。 Aph. flos-aquae、Aph. gracile 和 C. issatschenkoi 仅在温带地区有报道，而 S. aphanizomenoides 的分布范围最广，从热带到温带地区。Ch. ovalisporum 分布于热带、亚热带和地中海地区。虽然这五个物种在较宽的温度范围内（15-30°C）表现出中等的生长速度（0.1-0.4 天），但 Aph. gracile 和 Aph. flos-aquae 可以在 10°C 左右或以下生长，而 Ch. ovalisporum 和 S. aphanizomenoides 在 30°C 以上甚至接近 35°C 的高温下具有更强的竞争力。Aph. gracile 已被确认为 saxitoxins 和 cylindrospermopsin 的产生者，C. issatschenkoi 为 anatoxins 和 saxitoxins 的产生者，Ch. ovalisporum 为 cylindrospermopsin 的产生者。水华束丝藻或球形颤藻产生微囊藻毒素的可疑 cylin-drospermopsin 或anatoxin-a 生产仍不确定。本综述包括对毒性报告的可靠性以及在气候变化情景下“节旋藻属”物种的入侵潜力的批判性讨论，以及由此产生的知识差距和研究需求。总的来说，这项工作旨在为参与识别、预防和减轻有毒节旋藻水华的主要挑战的科学家和水管理人员提供关键参考。
