title: Quantitative Determination of the Spatial Distribution of Nitrosomonas europaea and Nitrobacter agilis Cells Immobilized in kappa-Carrageenan Gel Beads by a Specific Fluorescent-Antibody Labelling Technique.
abstract: A novel technique, combining labelling and stereological methods, for the determination of spatial distribution of two microorganisms in a biofilm is presented. Cells of Nitrosomonas europaea (ATCC 19718) and Nitrobacter agilis (ATCC 14123) were homogeneously distributed in a kappa-carrageenan gel during immobilization and allowed to grow out to colonies. The gel beads were sliced in thin cross sections after fixation and embedding. A two-step labelling method resulted in green fluorescent colonies of either N. europaea or N. agilis in the respective cross sections. The positions and surface areas of the colonies of each species were determined, and from that a biomass volume distribution for N. europaea and N. agilis in kappa-carrageenan gel beads was estimated. This technique will be useful for the validation of biofilm models, which predict such biomass distributions.
authors.affiliation: Department of Food Science, Food and Bioprocess Engineering Group, and Department of Plant Cytology and Morphology, Agricultural University, P.O. Box 8129, 6700 EV Wageningen, and Netherlands Institute for Ecology-Centre for Terrestrial Ecology, Heteren, The Netherlands.
authors.forename: J H
authors.initials: JH
authors.lastname: Hunik
authors.forename: M P
authors.initials: MP
authors.lastname: van den Hoogen
authors.forename: W
authors.initials: W
authors.lastname: de Boer
authors.forename: M
authors.initials: M
authors.lastname: Smit
authors.forename: J
authors.initials: J
authors.lastname: Tramper