Role of toxin genes in juvenile pearl oyster mortality syndrome

Role of toxin genes in juvenile pearl oyster mortality syndrome

Advisor/s

Professor Dean Jerry

College or Research Centre

College of Science & Engineering

Summary of Project

A decade ago pearl farming was one of the major employers and contributors to the social-economic fabric of northern Australia, contributing $189.7 million farm-gate to the national economy and generating another $200 million in tourism related activities. However, in recent years Australian pearl production has been severely impacted by episodic and large-scale mortality events by an as yet unidentified causative factor. This causative factor impacts within the first few months of grow-out when juvenile oysters are stocked into the ocean and often result in upwards of 90% mortality. These mortality events, termed juvenile pearl oyster mortality syndrome (or JPOMS), have resulted in massive write-downs in production and economic value of the industry and led to uncertainty within the future of the industry. The cause of JPOMS is unknown, but when an outbreak is first detected it generally sweeps rapidly through farm nursery areas suggesting a pathogenic agent is responsible for the syndrome. The causative agent has yet to be identified despite intensive investigation, but one possibility is that JPOMS is related to an organism that is always present but becomes pathogenic through the expression of toxin genes carried in bacterial plasmids under certain environmental conditions. In fact, plasmid transmitted toxin genes (Pir A &B) have been shown to be the causative agent for the recent pandemic of early mortality syndrome (or AHPND) in farmed shrimp and are associated with Vibrio spp. The occurrence of possible toxin genes, however, has not been extensively examined in pearl oysters subject to JOMS. This project, which will be a collaboration between Prof Dean Jerry from JCU https://research.jcu.edu.au/portfolio/dean.jerry/, Cygnet Bay Pearls, and Clipper Pearls, will use next generation sequencing, bioinformatic analyses, and histological approaches to look for the occurrence of likely toxin genes and their association with onset of JOMS in Australian pearl oysters. Enquiries to: dean.jerry@jcu.edu.au

Key Words

aquaculture; genetic tools; pearl oyster mortality syndrome; JPOMS; genes

Would suit an applicant who

Available to both domestic and international applicants wishing to undertake a PhD or Masters by research degree. Applicants will need to apply for a JCU competitive Research Scholarship and should be familiar with the Higher Degree by Research Requirements.

Updated: 11 Apr 2020