Sample and Predict harmful algae blooms.

In many aquatic ecosystems world-wide, including drinking water supplies, cyanobacteria and dinoflagellates can proliferate into the so-called harmful algal blooms (HAB). Members of these microbial phyla can produce an unparalleled array of bioactive secondary metabolites; some of which are potent toxins. The past ten years has witnessed major advances in our understanding of the genetic basis for toxin production by a number of groups of these microorganisms. 

Genomic information related to toxin synthesis has also indicated their environmental and cellular regulators, as well as associated transport mechanisms. The information gained from the discovery of these toxin biosynthetic pathways has also enabled the genetic screening of various environments for drinking water and seafood quality management. 

Cyanobacteria toxins are produced by many strains of cyanobacteria spanning multiple genera, however, as toxicity is not uniform among strains, conventional bacteriological classification methods are unable to accurately predict toxicity and analytical methods for the detection of the toxins often take days to perform and are not predictive. It has long since been realized that early detection methods for toxic cyanobacteria are critical as the consumption of cyanotoxins can lead to a myriad of serious health effects and can be fatal in high doses.

The synthesis of saxitoxin in dinoflagellates occupying marine environments has been recently found to be catalysed by a group of enzymes encoded by sxt genes, beginning with the unusual gene, sxtA. A quantitative PCR assay targeting sxtA gene to detect saxitoxin-producing dinoflagellates in marine environmental samples is being developed for use in marine environment management. The abundance of sxtA correlates with the abundance of the saxitoxin-producing species of such as Alexandrium species. Using this assay, detection and quantification of sxtA in HAB events in Australia and New Zealand has been correlated with saxitoxin uptake in shellfish.

Diagnostic Technology is developing and validating a molecular based test for the detection of cyanotoxin production in fresh, brackish and marine water environments, that pose a direct threat to public health. The CyanoDTec is a simple molecular assay for the simultaneous detection of hepatotoxins such as microcystin, nodularin and cylindrospermopsin and neurotoxins such as saxitoxin.

News, Developments and Publications:

• Alliance of Coastal Technologies (ACT) releases technical demonstration report for the Phytoxigene™ DinoDTec and CyanoDTec quantitative real-time PCR (qPCR) kits. ACT is a partnership of research institutions, resource managers, and private sector companies dedicated to fostering the development and adoption of effective and reliable sensors and platforms for use in coastal, freshwater and ocean environments. ACT conducts two levels of Technology Evaluations: Verifications and Demonstrations. Technology Verifications focus on classes of commercially available instruments to provide confirmation that each technology meets the manufacturer's performance specifications or claims and/or provides verified data on those operational parameters that stakeholders require to make a use decision. The report is available here.

• CyanoDTec has been assessed as having reached Pioneer Stage (Production & Implementation) in the Water Research Foundation/Water Environment Foundation LIFT program to accelerate innovation into practice. The LIFT Link allows users to Discover new technologies and research needs and is an online platform which serves as a highway of interaction among municipal and industrial water, wastewater, and stormwater agencies, technology providers, consultants, academics, investors, federal agencies, NGOs, and others for advancing innovation.

• Professor Brett Neilan, University of Newcastle and Diagnostic Technology have been awarded a Australian Research Council, Linkage Project Grant for the development of a novel biosynthetic platform for commercially valuable saxitoxins.

• An innovative passive sampling approach for the detection of cyanobacterial gene targets in freshwater sources. Science of The Total Environment, Volume 892, 2023,

• McKindles KM et al A Multiplex Analysis of Potentially Toxic Cyanobacteria in Lake Winnipeg during the 2013 Bloom Season. Toxins (Basel). 2019 Oct 11;11(10)

• J.D. Chaffin et al., Cyanobacterial blooms in the central basin of Lake Erie: Potentials for cyanotoxins and environmental drivers, Journal of Great Lakes Research

• Crawford A et al, Use of three monitoring approaches to manage a major Chrysosporum ovalisporum bloom in the Murray River, Australia, 2016. Environ Monit Assess. 2017 Apr;189(4):202

• NOAA; Hitting it where it hurts; The untold story of harmful algae blooms

• American Water Works Association (AWWA) - Use an Integrated Approach to Monitor Algal Blooms

• Algae Outbreaks Rose 40 Percent in 2018

• Stories of Australian Science cover the development of DinoDTec

• ABC story on the shellfish farming testing and management