The goal of this symposium was to cover the various important aspects of immobilized cells and to bring together scientists from different disciplines. In view of the projected importance of the use of immobilized cells in future biotechnological processes, it is essential that a better insight into the physiology of immobilized cells is obtained. The performance of artificially immobilized cells was compared with the role immobilized cells play in nature, and both physico-chemical and physiological aspects were handled. Special attention was given to novel approaches in the study of immobilized cells since the study of such cells today is not only based on traditional cultivation experiments but also depends very much on sophisticated physico-chemical instrumentation. Since the physiological conditions of immobilized cells is becoming increasingly important, a better understanding will facilitate the prediction of behaviour of certain cells when immobilized. Furthermore, a development is foreseen towards employing various means to modulate microbial physiology in desirable directions.
(Due to space limitations, only a random selection of papers are listed below. The number of papers in each section is given in parentheses). Opening Lectures (2). Conversions by immobilized cells versus traditional fermentations (J. Tramper). Immobilized cells in nature and their physiology (10). Surfaces and bacteria in natural environments - Nature's banquet table? (M. Fletcher). Comparative physiology of naturally and artificially immobilized Anabaena azollae (M. Brouers et al.). Bacterial biofilm sloughing: Nutrient limitation effects (D.H. Applegate and J.D. Bryers). Artificially immobilized cells and performance (31). Ethanol production by Zymomonas mobilis in a fluidized bed fermenter (M.J. Dempsey). Immobilized light-emitting E. coli cells expressing LUX genes (K.E. *aOAkerman et al.). Effect of glucose on the level of invertase activity yeast cells immobilized by a novel technique (P. Parascandola et al.). Cell immobilization in thermogels: Activity retention after gelling in various organic solvents (R.M. Buitelaar et al.). Recombinant human erythropoietin production by Bowes melanoma cells in alignate beads (L. Keay et al.). Comparative investigations on the physiological parameters of free and immobilized yeast cells for effective treatment of dairy effluents (S.S. Marwaha et al.). Characterization of the rotating nozzle-ring technique for the production of small spherical biocatalysts (M. Siemann et al.). H 2 S removal by immobilized Rhodococcus sp. 261 (Y. Ohta et al.). Membrane properties of mammalian neurons immobilized in calcium alginate beads (M. Simonneau et al.). Unexpected discovery and production of novel site-specific peptidase with immobilized yeast cells (K. Sonomoto et al.). Application of polyvinyl alcohol cryogels for immobilization of mesophilic and thermophilic microorganisms (S.D. Varfolomeyev et al.). The micro-environment: Physico-chemical aspects (21). The micro-environment of immobilized cells: Critical assessment of the influence of surfaces and local concentrations (P.G. Rouxhet and N. Mozes). Screening for matrices for viable cells (C. Syldatk et al.). Studies on the production of b-glucanase by free and immobilized recombinant yeast cells (G. Cahill et al.). Photosynthetic, respiratory and photorespiratory activities in Chlamydomonas reinhardtii cells entrapped in alginate matrix (F. Galvan et al.). Change of the microbial activity after immobilization of microorganisms (L.N. Nikolov and D.G. Karamanev). The environment: Physiological aspects (19). Physiological aspects of immobilized cells: A general overview (B. Hahn-Hagerdal). Morphological and physiological peculiarities of Gluconobacter oxydans cells entrapped in natural and synthetic polymer gels (M.V. Donova et al.). Improved production of ethanol and n-butanol in immobilized cell bioreactors (L. Keay et al.). Immobilized cell antibiotic production (F.J. Morgan and C. Webb).