Binding of Escherichia coli to Penrose Rubber Drains — in vitro Study

Ten different isolates of Escherichia coli were used to compare bacterial attachment to Penrose rubber drains at different temperatures and to investigate a possible relation with cell surface hydrophobicity and charges, as well as the capacity of autoaggregation. Penrose rubber drain pieces of 1 cm² were incubated with 4.8 × 10⁶E. coli cells for 1 h at 22, 37 and 42 °C, respectively. After rinsing with phosphate buffered saline (PBS), the number of adhering bacteria on the drain pieces was calculated by measuring cellular ATP (adenosine triphosphate) bioluminescence. Bacterial cell surface properties at different temperatures were determined by two-phase partitioning and autoaggregation was determined by arbitrary scoring under the dissecting microscope. For most strains of E. coli, the number of adherence to Penrose rubber drain was higher at 22 °C than at 37 °C and 42 °C. Bacterial cell-surface properties and autoaggregation capacity were influenced by the growth temperature, but without correlation to bacterial ability to attach to rubber drains. Thus, the present study demonstrates that attachment of E. coli to Penrose rubber drains was significantly influenced by temperature, but bacterial cell-surface hydrophobicity and charge as well as autoaggregation capacity had no influence on bacterial attachment ability.