Cell surface analysis often requires manipulation of cells prior to examination. The most commonly employed procedures are centrifugation at different speeds, changes of media during washing or final resuspension, desiccation (either air drying for contact angle measurements or freeze-drying for sensitive spectroscopic analysis, such as X-ray photoelectron spectroscopy), and contact with hydrocarbon (hydrophobicity assays). The effects of these procedures on electrophoretic mobility, adhesion to solid substrata, affinity to a number of Sepharose columns, structural integrity, and cell viability were systematically investigated for a range of model organisms, including carbon- and nitrogen-limited Psychrobacter sp. strain SW8 (glycocalyx-bearing cells), Escherichia coli(gram-negative cells without a glycocalyx), and Staphylococcus epidermidis (gram-positive cells without a glycocalyx). All of the cell manipulation procedures severely modified the physicochemical properties of cells, but with each procedure some organisms were more susceptible than others. Considerable disruption of cell surfaces occurred when organisms were placed in contact with a hydrocarbon (hexadecane). The majority of cells became nonculturable after air drying and freeze-drying. Centrifugation at a high speed (15,000 × g) modified many cell surface parameters significantly, although cell viability was considerably affected only in E. coli. The type of washing or resuspension medium had a strong influence on the values of cell surface parameters, particularly when high-salt solutions were compared with low-salt buffers. The values for parameters obtained with different methods that allegedly measure similar cell surface properties did not correlate for most cells. These results demonstrate that the methods used to prepare cells for cell surface analysis need to be critically investigated for each microorganism so that the final results obtained reflect the nature of the in situ microbial cell surface as closely as possible. There is an urgent need for new, reliable, nondestructive, minimally manipulative cell surface analysis techniques that can be used in situ.

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Shallow (5–13 m) and deep (35–65 m) groundwaters were evaluated for their ability to generate conditioning films which affect bacterial adhesion to natural (sandstone, shale, andesite) and man‐made substrata (polypropylene, stainless steel). Water contact angles indicated that all water samples produced conditioning films. Most films modified retention of the nonmotile Gram‐negative bacterium SW8, but attachment of the organism did not correlate with water contact angles. Each borewater produced conditioning films with a characteristic attachment profile of SW8. Films adsorbed from standing borewaters often retained SW8 in different numbers than coatings derived from pumped bores. Groundwater chemistry was very heterogeneous and microbiological data indicated the presence of a diverse aerobic and anaerobic microbial community. These results indicate that conditioning films derived from dissolved compounds may play a significant role in controlling the interaction of bacteria with substrata in the subsurface.