Proof of concept electrochemical sensor as a non-invasive diagnostic tool for the presence fungal pathogens
Lead Research Organisation:
Manchester Metropolitan University
Department Name: School of Science and the Environment
Abstract
Chytrid is the name given to a group of fungi that are capable of infecting and causing significant harm to amphibians such as frogs. The fungi can pass from amphibian-to-amphibian by direct contact or Chytrid can survive in the environment (such as in water) where it can be picked up and cause an infection. Following infection from Chytrid, amphibians can become lethargic, eat less, display poor swimming ability and skin complaints, and can result in death. Chytrid has been responsible for the decline of at least 501 amphibian species, with 90 species confirmed or presumed extinct in the wild and a further 124 species experiencing a reduction of over 90% abundance, signifying the greatest loss of biodiversity attributable to a pathogen.
Chytrid is now widespread in the wild across the globe, and as such, strategies have been developed to save populations using chambers (tanks) that are kept under strict conditions to allow the amphibians to thrive whilst keeping them free of infection. To ensure this is successful, it is essential those trying to save the amphibians can detect the presence of Chytrid and enact plans to keep the amphibians safe from infection. Currently, existing methods of detection require complex equipment, specialised training, and can be expensive and time consuming. To ensure researchers and conservationists are well equipped in the fight against Chytrid, a more efficient and cheaper detection method is required.
As part of the life cycle of Chytrid, cells produce 'volatile organic compounds' - these compounds can be noted by smell. Each species of fungi can produce them, but each species is likely to produce different selections of compounds, meaning the particular compounds produced by Chytrid are likely unique. In this project we will measure the compounds produced by Chytrid to discover this unique pattern of compounds, and then use advanced engineering techniques to understand if we can detect and measure these signature compounds (which would infer the presence of Chytrid) using a cheap, easy-to-use, reproducible and instant sensor technology known as screen-printed electrochemistry.
The diagnostic tool being developed through this project will aid conservation efforts to sustain healthy amphibian populations. It will also contribute to better understanding and combating Chytrid infections.
Chytrid is now widespread in the wild across the globe, and as such, strategies have been developed to save populations using chambers (tanks) that are kept under strict conditions to allow the amphibians to thrive whilst keeping them free of infection. To ensure this is successful, it is essential those trying to save the amphibians can detect the presence of Chytrid and enact plans to keep the amphibians safe from infection. Currently, existing methods of detection require complex equipment, specialised training, and can be expensive and time consuming. To ensure researchers and conservationists are well equipped in the fight against Chytrid, a more efficient and cheaper detection method is required.
As part of the life cycle of Chytrid, cells produce 'volatile organic compounds' - these compounds can be noted by smell. Each species of fungi can produce them, but each species is likely to produce different selections of compounds, meaning the particular compounds produced by Chytrid are likely unique. In this project we will measure the compounds produced by Chytrid to discover this unique pattern of compounds, and then use advanced engineering techniques to understand if we can detect and measure these signature compounds (which would infer the presence of Chytrid) using a cheap, easy-to-use, reproducible and instant sensor technology known as screen-printed electrochemistry.
The diagnostic tool being developed through this project will aid conservation efforts to sustain healthy amphibian populations. It will also contribute to better understanding and combating Chytrid infections.
Technical Summary
Batrachochytrium dendrobatidis and Batrachochytrium salamandrivorans (commonly known as Chytrid) are highly virulent fungal pathogens which can cause the fungal disease chytridiomycosis. Transmitted through the environment (water) or via direct amphibian-to-amphibian contact, infection with Chytrid can cause sub-lethal and lethal effects. Chytrid has been responsible for the decline of at least 501 amphibian species, with 90 species confirmed or presumed extinct in the wild and a further 124 species experiencing a reduction of over 90% abundance, signifying the greatest loss of biodiversity attributable to a pathogen. Chytrid is now widespread in the wild, and as such, strategies exist to preserve populations using amphibian ex situ environments. However, testing for the presence of the pathogen is still central to management and control. The existing methods requires expensive equipment, specialised training, can be costly and time consuming. To ensure researchers and conservationists are well equipped in the fight against Chytrid, a more efficient and cheaper detection method is required.
This project will assess the feasibility of a rapid, low-cost diagnostic sensor for the detection of Chytrid by assessing the microbial volatile organic compounds produced by Chytrid. These compounds (formed as part of either primary or secondary metabolic process, usually as side-products. MVOCs are typically small, odourous compounds with low molecular mass are greatly affected by particular species, growth conditions and other environmental factors, meaning each fungal species is likely to have a unique MVOC profile. Following quantification of Chytrid MVOC profiles, feasibility of screen-printed electrochemical sensors will be assessed. These sensors are widely considered to be cost effective, highly reproducible and sensitive towards the detection of target analytes.
This project will assess the feasibility of a rapid, low-cost diagnostic sensor for the detection of Chytrid by assessing the microbial volatile organic compounds produced by Chytrid. These compounds (formed as part of either primary or secondary metabolic process, usually as side-products. MVOCs are typically small, odourous compounds with low molecular mass are greatly affected by particular species, growth conditions and other environmental factors, meaning each fungal species is likely to have a unique MVOC profile. Following quantification of Chytrid MVOC profiles, feasibility of screen-printed electrochemical sensors will be assessed. These sensors are widely considered to be cost effective, highly reproducible and sensitive towards the detection of target analytes.
