AlgK is a TPR-containing Protein and the Periplasmic Component of a Novel Exopolysaccharide Secretin

Journal Article · Fri Jan 01 00:00:00 EST 2010 · Structure

DOI:https://doi.org/10.1016/j.str.2009.11.015· OSTI ID:1020010

Keiski, C; Harwich, M; Jain, S; Neculai, A; Whitney, J; Yip, P; Robinson, H; Riley, L; Burrows, L

The opportunistic pathogen Pseudomonas aeruginosa causes chronic biofilm infections in cystic fibrosis patients. During colonization of the lung, P. aeruginosa converts to a mucoid phenotype characterized by overproduction of the exopolysaccharide alginate. Here we show that AlgK, a protein essential for production of high molecular weight alginate, is an outer membrane lipoprotein that contributes to the correct localization of the porin AlgE. Our 2.5 {angstrom} structure shows AlgK is composed of 9.5 tetratricopeptide-like repeats, and three putative sites of protein-protein interaction have been identified. Bioinformatics analysis suggests that BcsA, PgaA, and PelB, involved in the production and export of cellulose, poly-{beta}-1,6-N-Acetyl-d-glucosamine, and Pel exopolysaccharide, respectively, share the same topology as AlgK/E. Together, our data suggest that AlgK plays a role in the assembly of the alginate biosynthetic complex and represents the periplasmic component of a new type of outer membrane secretin that differs from canonical bacterial capsular polysaccharide secretion systems.

• Research Organization: Brookhaven National Lab. (BNL), Upton, NY (United States). National Synchrotron Light Source
• Sponsoring Organization: DOE - OFFICE OF SCIENCE
• DOE Contract Number: DE-AC02-98CH10886
• OSTI ID: 1020010
• Report Number(s): BNL-95856-2011-JA; TRN: US201115%%646
• Journal Information: Structure, Vol. 18, Issue 2; ISSN 0969-2126
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE
ALGINATES
CELLULOSE
EXPORTS
FIBROSIS
LIPOPROTEINS
MEMBRANES
MOLECULAR WEIGHT
PATHOGENS
PATIENTS
PHENOTYPE
POLYSACCHARIDES
PORINS
PRODUCTION
PROTEINS
PSEUDOMONAS
SECRETIN
SECRETION
TOPOLOGY
national synchrotron light source