IMPACT OF DIFFERENT SUBSTRATES ON BIOMASS PROTEIN-COMPOSITION DURING WASTE-WATER TREATMENT INVESTIGATED BY 2-DIMENSIONAL ELECTROPHORESIS

The influence of different influent substrates on biomass protein comp osition was examined by two-dimensional polyacrylamide gel electrophor esis (2D-PAGE). Activated sludge from six sequencing batch reactors (S BRs) was investigated; four reactors were fed with model substrates an d two received effluents from a wood milling process and a paper produ ction process, respectively. Our investigations showed that in 2D-PAGE complex substrates caused a less diverse protein pattern than model w astewater composed of simple and low molecular weight compounds. This may be caused by complex formation by high molecular weight compounds of substrate with proteins, A more likely explanation is the presence of a more diversified microbial population resulting in a lower concen tration of individual proteins, so that detection limits after stainin g were too high to observe discrete spots. (C) 1998 IAWQ. Published by Elsevier Science Ltd.