Regulation of O antigen Chain Length in Pseudomonas aeruginosa

2011 ◽  
Author(s):  
Erica Nichole Kintz
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Chain Length ◽  
O Antigen

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 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 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.

Pseudomonas aeruginosa O-antigen chain length is determined before ligation to lipid A core

2002 ◽  
Vol 4 (12) ◽  
pp. 883-897 ◽  
Author(s):  
Craig Daniels ◽  
Corrie Griffiths ◽  
Bryony Cowles ◽  
Joseph S. Lam
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Chain Length ◽  
Lipid A ◽  
O Antigen

scholarly journals Unique Regions of the Polysaccharide Copolymerase Wzz2fromPseudomonas aeruginosaAre Essential for O-Specific Antigen Chain Length Control

2019 ◽  
Vol 201 (15) ◽  
Author(s):  
Steven M. Huszczynski ◽  
Chelsea Coumoundouros ◽  
Phi Pham ◽  
Joseph S. Lam ◽  
Cezar M. Khursigara
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Amino Acid ◽  
Chain Length ◽  
Virulence Factor ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
Content Type ◽  
O Antigen ◽  
Chain Lengths ◽  
Insight Into

ABSTRACTThe outer leaflet of the outer membrane of nearly all Gram-negative bacteria contains lipopolysaccharide (LPS). The distal end of LPS may be capped with O antigen, a long polysaccharide that can range from a few to hundreds of sugars in length. The chain length of the polysaccharide has many implications for bacterial survival and consequently is tightly controlled. In the Wzx/Wzy-dependent route of O antigen synthesis, one or more Wzz proteins determine the chain length via an unknown mechanism. To gain insight into this mechanism, we identified and characterized important regions of two Wzz proteins inPseudomonas aeruginosaserotype O13, which confer the production of “long” (Wzz1) and “very long” (Wzz2) chain lengths, respectively. We found that compared to Wzz1, Wzz2has distinct amino acid insertions in the central α-helices (insα6and insα7) and in membrane-distal (insL4) and -proximal (insIL) loops. When these regions were deleted in Wzz2, the mutant proteins conferred drastically shortened chain lengths. Within these regions we identified several conserved amino acid residues that were then targeted for site-directed mutagenesis. Our results implicate an RTE motif in loop 4 and a “hot spot” of charged and polar residues in insα7in the function of Wzz2. We present evidence that the functionally important residues of insα7are likely involved in stabilizing Wzz through coiled-coil interactions.IMPORTANCEO antigen is an important virulence factor presented on the cell surface of Gram-negative bacteria that is critical for bacterial physiology and pathogenesis. However, some aspects of O antigen biosynthesis, such as the mechanisms for determining polysaccharide chain length, are poorly understood. In this study, we identified unique regions in the O antigen chain length regulators (termed Wzz) of the problematic opportunistic pathogenPseudomonas aeruginosa. We show that these regions are critical for determining O antigen chain length, which provides new insight into the model of the Wzz mechanism. Ultimately, our work adds knowledge toward understanding an important step in the biosynthesis of this virulence factor, which is applicable to a wide range of Gram-negative pathogens.

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