Formation of 9-nm filaments from pilin monomers obtained by octyl-glucoside dissociation of Pseudomonas aeruginosa pili.

Pili isolated from Pseudomonas aeruginosa PAK were solubilized in the detergent octyl-glucoside. Subsequent removal of the detergent by dialysis resulted in the formation of short rods of about 9 nm in diameter and various lengths. The aggregation process was followed by ultracentrifugation, viscometry, and electron microscopy to show that the aggregates produced in this way are distinct from pili produced by the bacteria, both in diameter, as measured by electron micrographs, and in their inability to compete in a biological assay for pili.