Developing a predictive understanding of harmful cyanbacteria growth, toxins production and comparative toxicity across environmentally important gradients of n:p and salinity

项目总结 该项目将具体支持实现南卡罗来纳大学中心的总体目标 (南加州大学中心)及其总体具体目标，其中包括评估气候变化的影响(通过 温度、盐度、pH的变化以及痕量金属和微塑料的生物地球化学循环) 弧菌的耐药性和毒力与蓝藻的生长和产毒 对人类的饮用水、接触娱乐和海鲜安全暴露产生不利影响，这可能 导致弧菌感染增加、炎症增加和疾病(如非酒精性肝病) 在人类身上。尽管我们几十年前就知道，地表水的营养丰富可以导致 藻类过度生长，包括有害藻华(赤潮)的发展，其原因和 这些水华产生的毒素的后果最近受到了来自 环境公共卫生从业者。营养丰富，主要来自磷(P)和氮(N)， 增加沿淡水到海洋连续体的水华的频率和强度。然而，更少的是 已知N和P之间的化学计量相互作用如何跨越与环境相关的梯度， 特别是与盐度相结合时，可能会影响藻类的生长、毒素产生和比较毒性 蓝藻赤潮藻。气候变化会影响赤潮和盐度事件，这两种情况都可能改变 降水(干旱或洪水)和海平面上升的变化。鉴于生态研究和监测 以前的活动已经检查了“毒性”，这些努力通常由于缺乏强有力的分析而受到限制。 特定HAB种类产生的各种毒素的定量和通过 多种作用机制，包括水质状况的重大变化导致差异 对人类健康和生态系统的风险。这是对水管理的一个重要考虑。 资源和人类健康保护，因为藻类生长不一定能预测毒素 生产，但例行监测和监测活动，这是一项基本的环境公共卫生服务， 当这些努力确实存在时，使用蓝藻的显微方法，因此不要量化存在 有毒物质。如果进行了毒素分析，它最常用的是使用ELISA技术来检查是否存在 微囊藻毒素。此外，常用的水质模型缺乏毒素产生的输入，而毒素的产生本身就是 限制HAB事件的预测能力。蓝藻的一些物种进化出了独特的适应能力 在缺氮条件下促进它们的生长，但这些性状是否积极尚不清楚 与毒素的产生同时存在。发展预测生长、毒素生产和比较 通过本项目的具体目标提出的对通常占主导地位的蓝藻的毒性模型 因此，跨相关环境梯度的有毒HAB事件对于预测、诊断和 预防藻类毒素对人类健康构成的风险，藻类毒素似乎对 水资源评估与管理。

PROJECT SUMMARY This project will specifically support achieving the overarching goal of the University of South Carolina Center (USC Center) and its overall Specific Aim, which includes assessing the effects of climate change (through alterations in temperature, salinity, pH and biogeochemical cycling of trace metals and microplastics) on the antibiotic resistance and/virulence of Vibrio bacteria and the growth and toxins production by cyanobacteria that adversely affect drinking water, contact recreation and seafood safety exposure to humans, which may lead to increases in Vibrio infections, increased inflammation and disease (e.g., Non Alcoholic Liver Disease) in humans. Though we have known for decades that nutrient enrichment of surface waters can lead to excessive algal growth, including the development of harmful algal blooms (HABs), the causes and consequences of toxins produced by these blooms has recently received heightened attention from environmental public health practitioners. Nutrient enrichment, primarily from phosphorus (P) and nitrogen (N), increases the frequency and magnitude of blooms along the freshwater to marine continuum. However, less is known about how the stoichiometric interactions between N and P across environmentally relevant gradients, particularly in combination with salinity, may influence the growth, toxins production and comparative toxicity of cyanobacteria HABs. Climate change can affect incidents of HABs and salinity, which can be altered by both changes in precipitation (droughts or floods) and sea level rise. Whereas ecological studies and monitoring activities have previously examined “toxicity,” these efforts are routinely limited by absence of robust analytical quantitation of diverse toxins produced by specific HAB species and comparative toxicity exerted through multiple mechanisms of action including major alterations in water quality conditions resulting in differential risks to human health and ecosystems. This represents a critical consideration for management of water resources and protection of human health because algae growth does not necessarily predict toxins production, yet routine monitoring and surveillance activities, an essential environmental public health service, when these efforts do exist, use microscopic methods for cyanobacteria and thus do not quantify the presence of toxins. If toxins analysis occurs, it most commonly uses ELISA techniques to check for presence of microcystins. Further, commonly used water quality models lack inputs for toxins production, which inherently limits predictive capacity of HAB events. Some species of cyanobacteria have evolved unique adaptations to promote their growth under N-deficient conditions, but it remains unknown whether or not these traits actively exist simultaneously with toxins production. Developing predictive growth, toxins production and comparative toxicity models, proposed through the Specific Aims of this project, for cyanobacteria that commonly dominate toxic HAB events across relevant environmental gradients is thus imperative for forecasting, diagnosing and preventing human health risks presented by algal toxins, which appear to represent a transformative threat to water resources assessment and management.