title: Role of alginate O acetylation in resistance of mucoid Pseudomonas aeruginosa to opsonic phagocytosis.
abstract: Establishment and maintenance of chronic lung infections with mucoid Pseudomonas aeruginosa in patients with cystic fibrosis (CF) require that the bacteria avoid host defenses. Elaboration of the extracellular, O-acetylated mucoid exopolysaccharide, or alginate, is a major microbial factor in resistance to immune effectors. Here we show that O acetylation of alginate maximizes the resistance of mucoid P. aeruginosa to antibody-independent opsonic killing and is the molecular basis for the resistance of mucoid P. aeruginosa to normally nonopsonic but alginate-specific antibodies found in normal human sera and sera of infected CF patients. O acetylation of alginate appears to be critical for P. aeruginosa resistance to host immune effectors in CF patients.
authors.affiliation: Channing Laboratory, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115-5804, USA. gpier@channing.harvard.edu
authors.forename: G B
authors.initials: GB
authors.lastname: Pier
authors.forename: F
authors.initials: F
authors.lastname: Coleman
authors.forename: M
authors.initials: M
authors.lastname: Grout
authors.forename: M
authors.initials: M
authors.lastname: Franklin
authors.forename: D E
authors.initials: DE
authors.lastname: Ohman
mesh_terms: D000107:Acetylation; D000464:Alginates; D016667:Bacterial Capsules; D003167:Complement Activation; D003170:Complement Pathway, Alternative; D003550:Cystic Fibrosis / Q000150:complications; D006801:Humans; D008171:Lung Diseases / Q000150:complications / Q000209:etiology; D009895:Opsonin Proteins; D010587:Phagocytosis; D011552:Pseudomonas Infections / Q000150:complications / Q000209:etiology; D011550:Pseudomonas aeruginosa / Q000472:pathogenicity*
chemical_list: D000464:Alginates; D009895:Opsonin Proteins