Merck
  • Home
  • Search Results
  • Cadmium-induced formation of sulphide and cadmium sulphide particles in the aquatic hyphomycete Heliscus lugdunensis.

Cadmium-induced formation of sulphide and cadmium sulphide particles in the aquatic hyphomycete Heliscus lugdunensis.

Journal of trace elements in medicine and biology : organ of the Society for Minerals and Trace Elements (GMS) (2015-05-26)
Dirk Dobritzsch, Petra Ganz, Michael Rother, James Ehrman, Renate Baumbach, Jürgen Miersch
ABSTRACT

Freshwater fungi which can survive under metal exposure receive increasing scientific attention. Enhanced synthesis of sulphide and glutathione but no phytochelatin synthesis in response to cadmium (up to 80 μM Cd(2+) in the medium) was measured in the aquatic hyphomycete Heliscus lugdunensis. Up to 25 μmol g(-1) dry mass the fungus formed sulphide in an exponentially Cd(2+)-concentration-dependent manner. Using light microscopy, precipitates were observed outside of the hyphae which could be determined as amorphous particles by X-ray diffraction (XRD). Energy dispersive X-ray spectroscopy (EDS) analysis indicated that these particles were mainly composed of Cd and S with an atomic ratio of 1:1, but some elements of the culture medium such as P and Cl were also present. Fungal cells exposed to Cd(2+) accumulated 12-28 μmol metal g(-1) dry mass over a period of 7-28 days. The results may indicate that sulphide could sequester excess Cd(2+) under oxygen deprived conditions and thereby reduce its toxicity via an additional avoidance mechanism of this fungus.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Sulfuric acid, 99.999%