title: Pili of Aeromonas hydrophila: purification, characterization, and biological role.
abstract: Aeromonas hydrophila (Ae6) has 2 morphologically distinctive kinds of pili. One appeared rigid, channeled, and straight with a diameter of 9 nm (Ae6-R pili). The other looked flexible, wavy, and having helical structure with a diameter of 7 nm (Ae6-W pili). Ae6-R pili were purified and characterized. The pili consisted of a subunit protein with a molecular weight of 18 kDa as estimated by SDS-PAGE, and contained 42.3% hydrophobic amino acids and one cysteine residue. The pilus was solubilized to 18 kDa subunit protein by 2-mercaptoethanol, dithiothreitol, hydrochloric acid, or heating at 120 C for 5 min. The organism Ae6 was strongly adhesive to rabbit intestines as well as human intestines, and agglutinated erythrocytes. Anti-pili antibody (Fab fraction) did not block the adhesion. Purified Ae6-R pili did not adhere to the intestine or to the erythrocytes. However, the anti-pili Fab inhibited pellicle formation of the organisms cultured in broth, and also inhibited salt agglutination with ammonium sulfate. From these results, Ae6-R pili are not likely a colonization factor but probably play a role in the autoaggregation of the organisms.
authors.affiliation: Department of Bacteriology, University of the Ryukyus School of Medicine, Okinawa.
authors.forename: Y
authors.initials: Y
authors.lastname: Honma
authors.forename: N
authors.initials: N
authors.lastname: Nakasone
mesh_terms: D000333:Aeromonas / Q000502:physiology / Q000648:ultrastructure*; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D000907:Antibodies, Bacterial / Q000276:immunology; D001422:Bacterial Adhesion; D015153:Blotting, Western; D005243:Feces / Q000382:microbiology; D010861:Fimbriae, Bacterial / Q000502:physiology / Q000648:ultrastructure*; D006384:Hemagglutination; D006801:Humans; D007422:Intestines / Q000382:microbiology / Q000502:physiology; D008855:Microscopy, Electron, Scanning; D011817:Rabbits
chemical_list: D000596:Amino Acids; D000907:Antibodies, Bacterial