3E4B

Crystal structure of AlgK from Pseudomonas fluorescens WCS374r

Summary for 3E4B

• Entry DOI: 10.2210/pdb3e4b/pdb
• Descriptor: AlgK, CHLORIDE ION, GLYCEROL, ... (4 entities in total)
• Functional Keywords: algk, tetratricopeptide repeat, superhelix, alginate biosynthesis, pseudomonas, protein binding
• Biological source: Pseudomonas fluorescens
• Total number of polymer chains: 4
• Total formula weight: 198939.86

Authors

Keiski, C.-L.,Harwich, M.,Jain, S.,Neculai, A.M.,Yip, P.,Robinson, H.,Whitney, J.C.,Burrows, L.L.,Ohman, D.E.,Howell, P.L. (deposition date: 2008-08-11, release date: 2009-08-25, Last modification date: 2024-10-09)

Primary citation

Keiski, C.L.,Harwich, M.,Jain, S.,Neculai, A.M.,Yip, P.,Robinson, H.,Whitney, J.C.,Riley, L.,Burrows, L.L.,Ohman, D.E.,Howell, P.L.
AlgK is a TPR-containing protein and the periplasmic component of a novel exopolysaccharide secretin.
Structure, 18:265-273, 2010

PubMed Abstract: 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 A 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.

PubMed: 20159471
DOI: 10.1016/j.str.2009.11.015

Experimental method

X-RAY DIFFRACTION (2.5 Å)