scholarly journals Conserved-residue mutations in Wzy affect O-antigen polymerization and Wzz-mediated chain-length regulation in Pseudomonas aeruginosa PAO1

2013 ◽  
Vol 3 (1) ◽  
Author(s):  
Salim T. Islam ◽  
Steven M. Huszczynski ◽  
Timothy Nugent ◽  
Alexander C. Gold ◽  
Joseph S. Lam
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Chain Length ◽  
Pseudomonas Aeruginosa Pao1 ◽  
O Antigen ◽  
Length Regulation ◽  
Conserved Residue

scholarly journals Lipopolysaccharide O-Antigen Chain Length Regulation in Pseudomonas aeruginosa Serogroup O11 Strain PA103

2007 ◽  
Vol 190 (8) ◽  
pp. 2709-2716 ◽  
Author(s):  
Erica Kintz ◽  
Jennifer M. Scarff ◽  
Antonio DiGiandomenico ◽  
Joanna B. Goldberg
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Chain Length ◽  
Gene Mutations ◽  
Side Chain ◽  
Wild Type ◽  
O Antigen ◽  
Length Regulation ◽  
O Antigens ◽  
Chain Lengths ◽  
Long Chain

ABSTRACT The Wzz proteins are important for determining the length of the O-antigen side chain attached to lipopolysaccharide (LPS). Several bacteria, including Pseudomonas aeruginosa strain PAO1 (serogroup O5), produce two such proteins responsible for the preference of two different chain lengths on the surface. Our group has previously identified one wzz gene (wzz1) within the O-antigen locus of P. aeruginosa strain PA103 (serogroup O11). In this study we have identified the second wzz gene (wzz2), located in the same region of the genome and with 92% similarity to PAO1's wzz2 gene. Mutations were generated in both wzz genes by interruption with antibiotic resistance cassettes, and the effects of these mutations were characterized. Wild-type PA103 prefers two O-antigen chain lengths, referred to as long and very long. The expression of the long O-antigen chain length was reduced in the wzz1 mutant, indicating the Wzz1 protein is important for this chain length preference. The wzz2 mutant, on the other hand, was missing O-antigens of the very long chain length, indicating the Wzz2 protein is responsible for the production of very long O-antigen. The effects of the wzz mutations on virulence were also investigated. In both serum sensitivity assays and a mouse pneumonia model of infection, the wzz1 mutants exhibited greater defects in virulence compared to either wild-type PA103 or the wzz2 mutant, indicating the long chain length plays a greater role during these infectious processes.

scholarly journals Pseudomonas aeruginosa B-band O-antigen chain length is modulated by Wzz (Ro1).

1997 ◽  
Vol 179 (5) ◽  
pp. 1482-1489 ◽  
Author(s):  
L L Burrows ◽  
D Chow ◽  
J S Lam
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Chain Length ◽  
O Antigen

scholarly journals Remodeling of O Antigen in MucoidPseudomonas aeruginosavia Transcriptional Repression ofwzz2

mBio ◽  
2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Ashley R. Cross ◽  
Joanna B. Goldberg
Keyword(s):  
Cystic Fibrosis ◽  
Pseudomonas Aeruginosa ◽  
Chain Length ◽  
Transcriptional Repression ◽  
Antigen Expression ◽  
Opportunistic Pathogen ◽  
Negative Regulator ◽  
Content Type ◽  
O Antigen ◽  
Alginate Production

ABSTRACTPseudomonas aeruginosais an opportunistic pathogen that causes chronic lung infections in people with cystic fibrosis (CF). ChronicP. aeruginosaisolates generally do not express O antigen and often have a mucoid phenotype, which is characterized by the overproduction of the exopolysaccharide alginate. Therefore, O antigen expression and the mucoid phenotype may be coordinately regulated upon chronic adaption to the CF lung. Here we demonstrate that PDO300, a mucoid strain derived from the nonmucoid laboratory isolate PAO1, does not produce very long O antigen due to decreased expression of Wzz2, the very long O antigen chain length control protein, and that mucoid clinical isolates express reduced levels of Wzz2 compared to nonmucoid isolates. Further, we show that forcing the expression of very long O antigen by PDO300, by providingwzz2intrans, does not alter alginate production, suggesting that sugar precursors are not limited between the two biosynthesis pathways. Moreover, we confirm that AmrZ, a transcription factor highly expressed in mucoid strains, is a negative regulator ofwzz2promoter activity and very long O antigen expression. These experiments identify the first transcriptional regulator of O antigen chain length inP. aeruginosaand support a model where transition to a chronic mucoid phenotype is correlated with downregulation of very long O antigen through decreased Wzz2 production.IMPORTANCEDetection of mucoidPseudomonas aeruginosa, characterized by the overproduction of alginate, is correlated with the establishment of a chronic pulmonary infection and disease progression in people with cystic fibrosis (CF). In addition to the overproduction of alginate, loss of O antigen lipopolysaccharide production is also selected for in chronic infection isolates. In this study, we have identified the regulatory network that inversely regulates O antigen and alginate production. Understanding the regulation of these chronic phenotypes will elucidate mechanisms that are important for the establishment of a long-termP. aeruginosalung infection and ultimately provide an opportunity for intervention. PreventingP. aeruginosafrom chronically adapting to the CF lung environment could provide a better outcome for people who are infected.

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