title: Cadmium induces a novel metallothionein and phytochelatin 2 in an aquatic fungus.
abstract: Cadmium stress response was measured at the thiol peptide level in an aquatic hyphomycete (Heliscus lugdunensis). In liquid culture, 0.1 mM cadmium increased the glutathione (GSH) content and induced the synthesis of additional thiol peptides. HPLC, electrospray ionization mass spectrometry, and Edman degradation confirmed that a novel small metallothionein as well as phytochelatin (PC2) were synthesized. The metallothionein has a high homology to family 8 metallothioneins (http://www.expasy.ch/cgi-bin/lists?metallo.txt). The bonding of at least two cadmium ions to the metallothionein was demonstrated by mass spectrometry (MALDI MS). This is the first time that simultaneous induction of metallothionein and phytochelatin accompanied by an increase in GSH level has been shown in a fungus under cadmium stress, indicating a potential function of these complexing agents for in vivo heavy metal detoxification. The method presented here should be applicable as biomarker tool.
authors.affiliation: UFZ Centre for Environmental Research Leipzig-Halle in the Helmholtz Association, Department of Environmental Microbiology, Halle/Saale, Germany.
authors.forename: Petra
authors.initials: P
authors.lastname: Jaeckel
authors.forename: Gudrun
authors.initials: G
authors.lastname: Krauss
authors.forename: Sieglinde
authors.initials: S
authors.lastname: Menge
authors.forename: Angelika
authors.initials: A
authors.lastname: Schierhorn
authors.forename: Peter
authors.initials: P
authors.lastname: Rücknagel
authors.forename: Gerd-Joachim
authors.initials: GJ
authors.lastname: Krauss
mesh_terms: D001673:Biodegradation, Environmental; D002104:Cadmium / Q000493:pharmacokinetics* / Q000494:pharmacology*; D005978:Glutathione / Q000378:metabolism*; D008667:Metalloproteins / Q000378:metabolism*; D008668:Metallothionein / Q000378:metabolism*; D003904:Mitosporic Fungi / Q000145:classification / Q000187:drug effects / Q000378:metabolism*; D054811:Phytochelatins; D013045:Species Specificity; D018508:Water Purification / Q000379:methods
chemical_list: D008667:Metalloproteins; D002104:Cadmium; D008668:Metallothionein; D054811:Phytochelatins; D005978:Glutathione