PubMed | Macquarie University, University of Tasmania, Microbial Screening Technologies and CSIRO
Type: Journal Article | Journal: Marine drugs | Year: 2016
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/m) 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.
Ejje N.,University of Sydney |
Lacey E.,Microbial Screening Technologies |
Codd R.,University of Sydney
RSC Advances | Year: 2012
The potent histone deacetylase inhibitor trichostatin A (TSA) has been captured in a single step with high selectivity from the culture supernatant of the native TSA-producing strain Streptomyces hygroscopicus MST-AS5346 using analytical-scale Ni(ii)-based immobilised metal affinity chromatography. © 2012 The Royal Society of Chemistry.
Fremlin L.,University of Queensland |
Farrugia M.,University of Queensland |
Piggott A.M.,University of Queensland |
Khalil Z.,University of Queensland |
And 2 more authors.
Organic and Biomolecular Chemistry | Year: 2011
Chemical analysis of fermentation products from two Australian Streptomyces isolates yielded all four known and twelve new examples of the rare reveromycin class of polyketide spiroketals, including hemi-succinates, hemi-fumarates and hemi-furanoates. Reveromycins were identified with the aid of HPLC-DAD-MS and HPLC-DAD-SPE-NMR methodology, and structures were assigned by detailed spectroscopic analysis. The structural and mechanistic requirements for an unprecedented hemi-succinate:ketal-succinyl equilibrium were defined and provided a basis for proposing that reveromycin 4′-methyl esters and 5,6-spiroketals were artifacts. A plausible reveromycin polyketide biosynthesis is proposed, requiring a 2-methylsuccinyl-CoA starter unit, with flexible incorporation of a C6-8 polyketide chain extension and diacid esterification units. Structure activity relationship investigations by co-metabolites were used to assess the anticancer, antibacterial and antifungal properties of reveromycins. © 2011 The Royal Society of Chemistry.
Khalil Z.G.,University of Queensland |
Salim A.A.,University of Queensland |
Lacey E.,Microbial Screening Technologies |
Blumenthal A.,University of Queensland |
Capon R.J.,University of Queensland
Organic Letters | Year: 2014
A soil Streptomyces nov. sp. (MST-115088) isolated from semiarid terrain near Wollogorang Station, Queensland, returned two known and two new examples of a rare class of cyclic hexapeptide, desotamides A and B (1 and 2) and E and F (3 and 4), respectively, together with two new d-Orn homologues, wollamides A and B (5 and 6). Structures were assigned by detailed spectroscopic and C3 Marfey's analysis. The desotamides/wollamides exhibit growth inhibitory activity against Gram-positive bacteria (IC50 0.6-7 μM) and are noncytotoxic to mammalian cells (IC50 >30 μM). The wollamides exhibit antimycobacterial activity (IC50 2.8 and 3.1 μM), including reduction in the intracellular mycobacterial survival in murine bone marrow-derived macrophages. © 2014 American Chemical Society.
Emery N.J.,Microbial Screening Technologies |
Lacey E.,Microbial Screening Technologies
Seed Science and Technology | Year: 2010
There is considerable interest in establishing the flannel flower, Actinotus helianthi as a cut flower crop and commercial potted plant. This species is documented to have erratic germination, a feature common in many smoke-responsive plants. The present study proposes a foundation germination assay by optimizing the exposure of the seeds to smoke using an agar medium. Maximum germination was exhibited in two populations of A. helianthi when seeds were sown directly onto a 1% smoke water agar medium. It is recommended that future assays should adopt smoke water as a useful media for the germination of smoke-responsive plants.