title: Aspergillus Sydowii Marine Fungal Bloom in Australian Coastal Waters, Its Metabolites and Potential Impact on Symbiodinium Dinoflagellates.
abstract: Dust has been widely recognised as an important source of nutrients in the marine environment and as a vector for transporting pathogenic microorganisms. Disturbingly, in the wake of a dust storm event along the eastern Australian coast line in 2009, the Continuous Plankton Recorder collected masses of fungal spores and mycelia (~150,000 spores/m³) forming a floating raft that covered a coastal area equivalent to 25 times the surface of England. Cultured A. sydowii strains exhibited varying metabolite profiles, but all produced sydonic acid, a chemotaxonomic marker for A. sydowii. The Australian marine fungal strains share major metabolites and display comparable metabolic diversity to Australian terrestrial strains and to strains pathogenic to Caribbean coral. Secondary colonisation of the rafts by other fungi, including strains of Cladosporium, Penicillium and other Aspergillus species with distinct secondary metabolite profiles, was also encountered. Our bioassays revealed that the dust-derived marine fungal extracts and known A. sydowii metabolites such as sydowic acid, sydowinol and sydowinin A adversely affect photophysiological performance (Fv/Fm) of the coral reef dinoflagellate endosymbiont Symbiodinium. Different Symbiodinium clades exhibited varying sensitivities, mimicking sensitivity to coral bleaching phenomena. The detection of such large amounts of A. sydowii following this dust storm event has potential implications for the health of coral environments such as the Great Barrier Reef.
authors.affiliation: Institute for Marine &amp; Antarctic Studies, University of Tasmania, Hobart, Tasmania 7004, Australia. aiko.hayashi@utas.edu.au.
authors.forename: Aiko
authors.initials: A
authors.lastname: Hayashi
authors.affiliation: Microbial Screening Technologies, Building A, 28-54 Percival Rd, Smithfield NSW 2164, Australia. acrombie@microbialscreening.com.
authors.forename: Andrew
authors.initials: A
authors.lastname: Crombie
authors.affiliation: Microbial Screening Technologies, Building A, 28-54 Percival Rd, Smithfield NSW 2164, Australia. elacey@microbialscreening.com.
authors.forename: Ernest
authors.initials: E
authors.lastname: Lacey
authors.affiliation: CSIRO Marine &amp; Atmospheric Research, Ecosciences Precinct, Brisbane, Queensland 4102, Australia. anthony.richardson@csiro.au.|Centre for Applications in Natural Resource Mathematics, School of Mathematics and Physics, University of Queensland, St Lucia, Queensland 4072, Australia. anthony.richardson@csiro.au.
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Richardson
authors.affiliation: Microbial Screening Technologies, Building A, 28-54 Percival Rd, Smithfield NSW 2164, Australia. dvuong@microbialscreening.com.
authors.forename: Daniel
authors.initials: D
authors.lastname: Vuong
authors.affiliation: Department of Chemistry and Biomolecular Sciences, Macquarie University, NSW 2109, Australia. andrew.piggott@mq.edu.au.
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Piggott
authors.affiliation: Institute for Marine &amp; Antarctic Studies, University of Tasmania, Hobart, Tasmania 7004, Australia. gustaaf.hallegraeff@utas.edu.au.
authors.forename: Gustaaf
authors.initials: G
authors.lastname: Hallegraeff
mesh_terms: D000818:Animals; D001230:Aspergillus / Q000302:isolation & purification* / Q000378:metabolism; D001315:Australia; D057894:Coral Reefs; D004141:Dinoflagellida / Q000382:microbiology*; D004391:Dust; D005658:Fungi / Q000302:isolation & purification; D064210:Secondary Metabolism; D013172:Spores, Fungal / Q000302:isolation & purification*
chemical_list: D004391:Dust
keywords: Aspergillus sydowii; Symbiodinium; coral disease; maximum quantum yield (Fv/Fm); secondary metabolites; sydonic acid; sydonol; sydowinin; sydowinol