Microorganisms in soil as observed by staining with rhodamine-labeled lysozyme

Indigenous soil microorganisms on soil contact slides were stained with rhodamine-labeled lysozyme and counterstained with fluorescein-labeled gelatin. Bacteria and actinomycetes on these slide preparations were readily observed by fluorescence microscopy even if they occurred on or near soil particles. Many fungal hyphae were also stained by the fluorochrome-labeled lysozyme, and it is suggested that chitin, which is present in the cell walls of many fungi, is responsible for the fungal adsorption of lysozyme.