Molecular characterization of aromatic peroxygenase from Agrocybe aegerita.

Recently, a novel group of fungal peroxidases, known as the aromatic peroxygenases (APO), has been discovered. Members of these extracellular biocatalysts produced by agaric basidiomycetes such as Agrocybe aegerita or Coprinellus radians catalyze reactions--for example, the peroxygenation of naphthalene, toluene, dibenzothiophene, or pyridine--which are actually attributed to cytochrome P450 monooxygenases. Here, for the first time, genetic information is presented on this new group of peroxide-consuming enzymes.

The coprophilous mushroom Coprinus radians secretes a haloperoxidase that catalyzes aromatic peroxygenation.

Coprophilous and litter-decomposing species (26 strains) of the genus Coprinus were screened for peroxidase activities by using selective agar plate tests and complex media based on soybean meal. Two species, Coprinus radians and C. verticillatus, were found to produce peroxidases, which oxidized aryl alcohols to the corresponding aldehydes at pH 7 (a reaction that is typical for heme-thiolate haloperoxidases).

Stimulated embryo production as a parameter of estrogenic exposure via sediments in the freshwater mudsnail Potamopyrgus antipodarum.

The effects of three suspected endocrine disrupting chemicals, the xeno-estrogens bisphenol A (BPA), 4-tert-octylphenol (OP) and 4-n-nonylphenol (NP), were investigated in a whole-sediment biotest with the freshwater mudsnail Potamopyrgus antipodarum (Gastropoda, Prosobranchia). Artificial sediments were spiked with five nominal concentrations (six for NP), ranging from 1-300 microg/kg dry weight (1-1000 microg/kg for NP). After 2, 4 and 8 weeks of exposure, the responses of the test species were analysed.

Carcinogenesis and chemotherapy viewed from the perspective of stoichiometric network analysis (SNA): what can the biological system of the elements contribute to an understanding of tumour induction by elemental chemical noxae (e.g., Ni2+ , Cd2+ ) and to an understanding of chemotherapy?

The biological application of stoichiometric network analysis (SNA) permits an understanding of tumour induction, carcinogenesis, and chemotherapy. Starting from the Biological System of the Elements, which provides a comprehensive treatment of the functions and distributions of chemical (trace) elements in biology, an attempt is made to interrelate the essential feature of biology and--regrettably--of tumour genesis by superimposing SNA reasoning on common features of all crucial biological processes. For this purpose, aspects, effects and drawbacks of autocatalysis (identical reproduction which can occur either under control or without control [in tumours]) are linked with the known facts about element distributions in living beings and about interference of metals with tumours (in terms of both chemotherapy and carcinogenesis).

Toxicity of triphenyltin and tributyltin to the freshwater mudsnail Potamopyrgus antipodarum in a new sediment biotest.

The effects of two suspected endocrine-disrupting chemicals, the xeno-androgens triphenyltin (TPT) and tributyltin (TBT), were investigated in a new whole-sediment biotest with the freshwater mudsnail Potamopyrgus antipodarum (Gastropoda, Prosobranchia). Artificial sediments were spiked with seven concentrations, ranging from 10 to 500 microg nominal TPT-Sn/kg dry weight and TBT-Sn/kg dry weight, respectively. We analyzed the responses of the test species after two, four, and eight weeks exposure.

The German heavy metal survey by means of mosses.

This is the first attempt to determine pollution with metals throughout the Federal Republic of Germany by analysing moss samples. Samples of Pleurozium schreberi, Scleropodium purum, Hypnum cupessiforme and Hylocomium splendens were collected at 593 sites and analysed by ICP-AES and AAS for the elements As, Cd, Cr, Cu, Fe, Ni, Pb, V and Zn. Citrus leaves and pine needles were used as reference materials to ensure the quality of the results.