Colophon. Editors' preface. 1. Strategic views. Application of the biotechnological potential for environmental challenges in the chemical industry. G. Stucki, P. Steinle. 2. Molecular aspects of xenobiotic degradation. Molecular characterisation of key enzymes in halorespiration. H. Smidt, et al. Diversity and activity of microbes oxidizing methane and ammonium in northern organic soils under changing environmental conditions. P.J. Martikainen, et al. The haloalkane dehalogenase genes dhlA and dhaA are globally distrtibuted Microbial aspects in bioremediation of soils polluted by polyaromatic hydrocarbons. P. Wattiau. Transfer of catabolic plasmids in soil and activated sludge: a feasible bioaugmentation strategy? E.M. Top. Coping with a halogenated one-carbon diet: aerobic dichloromethane-mineralising bacteria. S. Vuilleumier. Microbial degradation of pollutants at low concentrations and in the presence of alternative carbon substrates: emerging patterns. T. Egli. Towards a better understanding of enhanced pesticide biodegradation. S.J. Goux, et al. Microbial degradation of chlorinated aromatic compounds. W. Reineke, et al. The role of environmental conditions and biotic interactions between microbial species in degradation of chlorinated pollutants. O. Drzyzga, et al. Characterised reactions in aerobic and anaerobic utilisation of linear alkylbenzenesulphonate (LAS). W. Dong, et al. Mechanisms involving the aerobic biodegradation of PCB in the environment. D.D. Focht, et al. Enzymology of the breakdown of synthetic chelating agents. T. Egli, M. Witschel. 4. Ecotoxicology. Transgenic nematodes as biosensors of environmental stress. D.I. De Pomerai, et al. Index.