Classification of a Proteus penneri clinical isolate with a unique O-antigen structure to a new Proteus serogroup, O80

ABSTRACT Proteus species are well-characterized opportunistic pathogens primarily associated with urinary tract infections (UTI) of humans. The Proteus O antigen is one of the most variable constituents of the cell surface, and O antigen heterogeneity is used for serological classification of Proteus isolates. Even though most Proteus O antigen structures have been identified, the O antigen locus has not been well characterized. In this study, we identified the putative Proteus O antigen locus and demonstrated this region's high degree of heterogeneity by comparing sequences of 40 Proteus isolates using PCR-restriction fragment length polymorphism (RFLP). This analysis identified five putative Proteus O antigen gene clusters, and the probable functions of these O antigen-related genes were proposed, based on their similarity to genes in the available databases. Finally, Proteus-specific genes from these five serogroups were identified by screening 79 strains belonging to the 68 Proteus O antigen serogroups. To our knowledge, this is the first molecular characterization of the putative Proteus O antigen locus, and we describe a novel molecular classification method for the identification of different Proteus serogroups.

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Extended-Spectrum Cephalosporinase in Acinetobacter baumannii

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00050-10 ◽

2010 ◽

Vol 54 (8) ◽

pp. 3484-3488 ◽

Cited By ~ 46

Author(s):

José-Manuel Rodríguez-Martínez ◽

Patrice Nordmann ◽

Esthel Ronco ◽

Laurent Poirel

Keyword(s):

Acinetobacter Baumannii ◽

Clinical Isolate ◽

Site Directed Mutagenesis ◽

Directed Mutagenesis ◽

Extended Spectrum ◽

Class C ◽

High Level ◽

Level Resistance

ABSTRACT An AmpC-type β-lactamase conferring high-level resistance to expanded-spectrum cephalosporins and monobactams was characterized from an Acinetobacter baumannii clinical isolate. This class C β-lactamase (named ADC-33) possessed a Pro210Arg substitution together with a duplication of an Ala residue at position 215 (inside the Ω-loop) compared to a reference AmpC cephalosporinase from A. baumannii. ADC-33 hydrolyzed ceftazidime, cefepime, and aztreonam at high levels, which allows the classification of this enzyme as an extended-spectrum AmpC (ESAC). Site-directed mutagenesis confirmed the role of both substitutions in its ESAC property.

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O-antigen structure and gene clusters of Escherichia coli O51 and Salmonella enterica O57; another instance of identical O-antigens in the two species

Carbohydrate Research ◽

10.1016/j.carres.2011.02.020 ◽

2011 ◽

Vol 346 (6) ◽

pp. 828-832 ◽

Cited By ~ 4

Author(s):

Andrei V. Perepelov ◽

Bin Liu ◽

Sof’ya N. Senchenkova ◽

Dan Guo ◽

Sergei D. Shevelev ◽

...

Keyword(s):

Escherichia Coli ◽

Salmonella Enterica ◽

Gene Clusters ◽

O Antigen ◽

O Antigens ◽

Antigen Structure

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Structure of the O-specific polysaccharide of Proteus penneri 71 and classification of cross-reactive P. penneri strains to a new proposed serogroup O64

European Journal of Biochemistry ◽

10.1046/j.1432-1327.2000.01059.x ◽

2000 ◽

Vol 267 (3) ◽

pp. 808-814 ◽

Cited By ~ 10

Author(s):

Krystyna Zych ◽

Nina A. Kocharova ◽

Marcin Kowalczyk ◽

Filip V. Toukach ◽

Dominika Kaminska ◽

...

Keyword(s):

Specific Polysaccharide ◽

Proteus Penneri

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Structure of the O-antigen of Salmonella O66 and the genetic basis for similarity and differences between the closely related O-antigens of Escherichia coli O166 and Salmonella O66

Microbiology ◽

10.1099/mic.0.037325-0 ◽

2010 ◽

Vol 156 (6) ◽

pp. 1642-1649 ◽

Cited By ~ 10

Author(s):

Bin Liu ◽

Andrei V. Perepelov ◽

Dan Li ◽

Sof'ya N. Senchenkova ◽

Yanfang Han ◽

...

Keyword(s):

Escherichia Coli ◽

Gene Cluster ◽

Gene Clusters ◽

Coding Region ◽

E Coli ◽

Antigen Gene ◽

O Antigen ◽

New Genes ◽

O Antigens ◽

Antigen Structure

O-antigen is a component of the outer membrane of Gram-negative bacteria and is one of the most variable cell surface constituents, leading to major antigenic variability. The O-antigen forms the basis for bacterial serotyping. In this study, the O-antigen structure of Salmonella O66 was established, which differs from the known O-antigen structure of Escherichia coli O166 only in one linkage (most likely the linkage between the O-units) and O-acetylation. The O-antigen gene clusters of Salmonella O66 and E. coli O166 were found to have similar organizations, the only exception being that in Salmonella O66, the wzy gene is replaced by a non-coding region. The function of the wzy gene in E. coli O166 was confirmed by the construction and analysis of deletion and trans-complementation mutants. It is proposed that a functional wzy gene located outside the O-antigen gene cluster is involved in Salmonella O66 O-antigen biosynthesis, as has been reported previously in Salmonella serogroups A, B and D1. The sequence identity for the corresponding genes between the O-antigen gene clusters of Salmonella O66 and E. coli O166 ranges from 64 to 70 %, indicating that they may originate from a common ancestor. It is likely that after the species divergence, Salmonella O66 got its specific O-antigen form by inactivation of the wzy gene located in the O-antigen gene cluster and acquisition of two new genes (a wzy gene and a prophage gene for O-acetyl modification) both residing outside the O-antigen gene cluster.

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O-antigen structure in a virulent strain ofAeromonas hydrophila

FEMS Microbiology Letters ◽

10.1111/j.1574-6968.1984.tb01319.x ◽

1984 ◽

Vol 24 (2-3) ◽

pp. 277-280 ◽

Cited By ~ 18

Author(s):

Derek H. Shaw ◽

M.Jeanne Squires

Keyword(s):

Virulent Strain ◽

O Antigen ◽

Antigen Structure

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Structural Determination and Genetic Identification of the O-Antigen from an Escherichia coli Strain, LL004, Representing a Novel Serogroup

International Journal of Molecular Sciences ◽

10.3390/ijms222312746 ◽

2021 ◽

Vol 22 (23) ◽

pp. 12746

Author(s):

Jing Wang ◽

Yujuan Xu ◽

Chunjun Qin ◽

Jing Hu ◽

Jian Yin ◽

...

Keyword(s):

Escherichia Coli ◽

Nmr Spectra ◽

Coli Strain ◽

Genetic Identification ◽

Gram Negative Bacteria ◽

Gram Negative ◽

E Coli ◽

O Antigen ◽

Antigen Structure ◽

Dependent Pathway

The O-antigen is the outermost component of the lipopolysaccharide layer in Gram-negative bacteria, and the variation of O-antigen structure provides the basis for bacterial serological diversity. Here, we determined the O-antigen structure of an Escherichia coli strain, LL004, which is totally different from all of the E. coli serogroups. The tetrasaccharide repeating unit was determined as →4)-β-d-Galp-(1→3)-β-d-GlcpNAc6OAc(~70%)-(1→3)-β-d-GalpA-(1→3)-β-d-GalpNAc-(1→ with monosaccharide analysis and NMR spectra. We also characterized the O-antigen gene cluster of LL004, and sequence analysis showed that it correlated well with the O-antigen structure. Deletion and complementation testing further confirmed its role in O-antigen biosynthesis, and indicated that the O-antigen of LL004 is assembled via the Wzx/Wzy dependent pathway. Our findings, in combination, suggest that LL004 should represent a novel serogroup of E. coli.

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O-antigen structure of Shigella flexneri serotype Yv and effect of the lpt-O gene variation on phosphoethanolamine modification of S. flexneri O-antigens

Glycobiology ◽

10.1093/glycob/cws222 ◽

2013 ◽

Vol 23 (4) ◽

pp. 475-485 ◽

Cited By ~ 20

Author(s):

Y. A. Knirel ◽

R. Lan ◽

S. N. Senchenkova ◽

J. Wang ◽

A. S. Shashkov ◽

...

Keyword(s):

Shigella Flexneri ◽

Gene Variation ◽

O Antigen ◽

O Antigens ◽

Antigen Structure

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Increased severity of respiratory infections associated with elevated anti-LPS IgG2 which inhibits serum bactericidal killing

Journal of Experimental Medicine ◽

10.1084/jem.20132444 ◽

2014 ◽

Vol 211 (9) ◽

pp. 1893-1904 ◽

Cited By ~ 38

Author(s):

Timothy J. Wells ◽

Deborah Whitters ◽

Yanina R. Sevastsyanovich ◽

Jennifer N. Heath ◽

John Pravin ◽

...

Keyword(s):

Respiratory Infections ◽

Natural Infection ◽

Gram Negative Bacteria ◽

Inhibitory Antibody ◽

Gram Negative ◽

O Antigen ◽

Excess Production ◽

Blocking Antibodies ◽

Antigen Structure ◽

Induce Antibody

Although specific antibody induced by pathogens or vaccines is a key component of protection against infectious threats, some viruses, such as dengue, induce antibody that enhances the development of infection. In contrast, antibody-dependent enhancement of bacterial infection is largely unrecognized. Here, we demonstrate that in a significant portion of patients with bronchiectasis and Pseudomonas aeruginosa lung infection, antibody can protect the bacterium from complement-mediated killing. Strains that resist antibody-induced, complement-mediated killing produce lipopolysaccharide containing O-antigen. The inhibition of antibody-mediated killing is caused by excess production of O-antigen–specific IgG2 antibodies. Depletion of IgG2 to O-antigen restores the ability of sera to kill strains with long-chain O-antigen. Patients with impaired serum-mediated killing of P. aeruginosa by IgG2 have poorer respiratory function than infected patients who do not produce inhibitory antibody. We suggest that excessive binding of IgG2 to O-antigen shields the bacterium from other antibodies that can induce complement-mediated killing of bacteria. As there is significant sharing of O-antigen structure between different Gram-negative bacteria, this IgG2-mediated impairment of killing may operate in other Gram-negative infections. These findings have marked implications for our understanding of protection generated by natural infection and for the design of vaccines, which should avoid inducing such blocking antibodies.

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