Distinct biological activity of lipopolysaccharides with different lipid a acylation status from mutant strains of Yersinia pestis and some members of genus Psychrobacter

The lipopolysaccharides LPS I and LPS II, isolated from the hypovirulent EV40 strain of Yersinia pestis, are composed only of type R lipopolysaccharides. This type consists of two forms, a and b, depending on their solubility pattern in a solvent mixture containing varying proportions of chloroform, methanol, hexane, and hydrochloric acid. LPS I consists of one subtype, RIb, while LPS II consists of two subtypes, RIIa and RIIb. Analysis by gel electrophoresis shows that the mass of these lipopolysaccharide forms are in the vicinity of 2000-3000 Da. The RIb and RIIb subtypes, which are found in the majority of lipopolysaccharide I and II fractions, are composed of ketoses and amines that are similar to those occurring in LPS I and LPS II. In contrast, the two subtypes RIIa and RIIb are different both in terms of the composition of lipid A and the extent of its substitution. Certain fractions of RIIa contain only lipid A and 3-deoxy-D-manno-octulosonic acid (KDO), while other fractions of RIIb possess a lipid A, which is not substituted by arabinose. The whole set of these R-type lipopolysaccharide forms are excellent models for the study of the role of the primary structure of the polysaccharide region, and for the effect of lipid A substitution on the biological activity of bacterial lipopolysaccharides.Key words: Yersinia pestis, hypovirulence, lipopolysaccharides, R type.[Journal translation]

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Structural and Functional Properties and Biological Activity of the Capsule Antigen 'Murine' Toxin and Yersinia Pestis Endotoxin

10.21236/ada241776 ◽

1991 ◽

Author(s):

Zh. M. Isin ◽

T. I. Tugambayev

Keyword(s):

Biological Activity ◽

Yersinia Pestis ◽

Functional Properties ◽

Structural And Functional Properties

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Bacterial Endotoxins: Relationships between Chemical Structure and Biological Activity of the Inner Core-Lipid a Domain

Microbial Surface Components and Toxins in Relation to Pathogenesis ◽

10.1007/978-1-4684-8995-8_23 ◽

1991 ◽

pp. 209-217 ◽

Cited By ~ 2

Author(s):

Ernst Th. Rietschel ◽

Lore Brade ◽

Ulrich Schade ◽

Ulrich Seydel ◽

Ulrich Zähringer ◽

...

Keyword(s):

Biological Activity ◽

Chemical Structure ◽

Lipid A ◽

Inner Core ◽

Core Lipid ◽

Bacterial Endotoxins

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The amoebae plate test implicates a paralogue of lpxB in the interaction of Legionella pneumophila with Acanthamoeba castellanii

Microbiology ◽

10.1099/mic.0.27563-0 ◽

2005 ◽

Vol 151 (1) ◽

pp. 167-182 ◽

Cited By ~ 36

Author(s):

Urs Albers ◽

Katrin Reus ◽

Howard A. Shuman ◽

Hubert Hilbi

Keyword(s):

Legionella Pneumophila ◽

Lipid A ◽

Sequence Similarity ◽

Acanthamoeba Castellanii ◽

Growth Defect ◽

Wild Type ◽

Intracellular Growth ◽

Plate Test ◽

Raw264.7 Macrophages ◽

Mutant Strains

Legionella pneumophila is a bacterial parasite of freshwater amoebae which also grows in alveolar macrophages and thus causes the potentially fatal pneumonia Legionnaires' disease. Intracellular growth within amoebae and macrophages is mechanistically similar and requires the Icm/Dot type IV secretion system. This paper reports the development of an assay, the amoebae plate test (APT), to analyse growth of L. pneumophila wild-type and icm/dot mutant strains spotted on agar plates in the presence of Acanthamoeba castellanii. In the APT, wild-type L. pneumophila formed robust colonies even at high dilutions, icmT, -R, -P or dotB mutants failed to grow, and icmS or -G mutants were partially growth defective. The icmS or icmG mutant strains were used to screen an L. pneumophila chromosomal library for genes that suppress the growth defect in the presence of the amoebae. An icmS suppressor plasmid was isolated that harboured the icmS and flanking icm genes, indicating that this plasmid complements the intracellular growth defect of the mutant. In contrast, different icmG suppressor plasmids rendered the icmG mutant more cytotoxic for A. castellanii without enhancing intracellular multiplication in amoebae or RAW264.7 macrophages. Deletion of individual genes in the suppressor plasmids inserts identified lcs (Legionella cytotoxic suppressor) -A, -B, -C and -D as being required for enhanced cytotoxicity of an icmG mutant strain. The corresponding proteins show sequence similarity to hydrolases, NlpD-related metalloproteases, lipid A disaccharide synthases and ABC transporters, respectively. Overexpression of LcsC, a putative paralogue of the lipid A disaccharide synthase LpxB, increased cytotoxicity of an icmG mutant but not that of other icm/dot or rpoS mutant strains against A. castellanii. Based on sequence comparison and chromosomal location, lcsB and lcsC probably encode enzymes involved in cell wall maintenance and peptidoglycan metabolism. The APT established here may prove useful to identify other bacterial factors relevant for interactions with amoeba hosts.

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Early evolutionary loss of the lipid A modifying enzyme PagP resulting in innate immune evasion in Yersinia pestis

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1917504117 ◽

2020 ◽

Vol 117 (37) ◽

pp. 22984-22991 ◽

Cited By ~ 3

Author(s):

Courtney E. Chandler ◽

Erin M. Harberts ◽

Mark R. Pelletier ◽

Iyarit Thaipisuttikul ◽

Jace W. Jones ◽

...

Keyword(s):

Yersinia Pestis ◽

Immune Evasion ◽

Lipid A ◽

Yersinia Pseudotuberculosis ◽

Innate Immune ◽

Nucleotide Polymorphism ◽

Single Nucleotide ◽

Structural Modifications ◽

Tlr4 Signaling Pathway ◽

Innate Immune Evasion

Immune evasion through membrane remodeling is a hallmark of Yersinia pestis pathogenesis. Yersinia remodels its membrane during its life cycle as it alternates between mammalian hosts (37 °C) and ambient (21 °C to 26 °C) temperatures of the arthropod transmission vector or external environment. This shift in growth temperature induces changes in number and length of acyl groups on the lipid A portion of lipopolysaccharide (LPS) for the enteric pathogens Yersinia pseudotuberculosis (Ypt) and Yersinia enterocolitica (Ye), as well as the causative agent of plague, Yersinia pestis (Yp). Addition of a C16 fatty acid (palmitate) to lipid A by the outer membrane acyltransferase enzyme PagP occurs in immunostimulatory Ypt and Ye strains, but not in immune-evasive Yp. Analysis of Yp pagP gene sequences identified a single-nucleotide polymorphism that results in a premature stop in translation, yielding a truncated, nonfunctional enzyme. Upon repair of this polymorphism to the sequence present in Ypt and Ye, lipid A isolated from a Yp pagP+ strain synthesized two structures with the C16 fatty acids located in acyloxyacyl linkage at the 2′ and 3′ positions of the diglucosamine backbone. Structural modifications were confirmed by mass spectrometry and gas chromatography. With the genotypic restoration of PagP enzymatic activity in Yp, a significant increase in lipid A endotoxicity mediated through the MyD88 and TRIF/TRAM arms of the TLR4-signaling pathway was observed. Discovery and repair of an evolutionarily lost lipid A modifying enzyme provides evidence of lipid A as a crucial determinant in Yp infectivity, pathogenesis, and host innate immune evasion.

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Induction of Protective Antiplague Immune Responses by Self-Adjuvanting Bionanoparticles Derived from Engineered Yersinia pestis

Infection and Immunity ◽

10.1128/iai.00081-20 ◽

2020 ◽

Vol 88 (5) ◽

Cited By ~ 2

Author(s):

Xiuran Wang ◽

Amit K. Singh ◽

Xiangmin Zhang ◽

Wei Sun

Keyword(s):

Immune Responses ◽

Yersinia Pestis ◽

Rational Design ◽

Lipid A ◽

Vaccine Development ◽

Lethal Dose ◽

Outer Membrane Vesicles ◽

Vector System ◽

Content Type ◽

Monophosphoryl Lipid A

ABSTRACT A Yersinia pestis mutant synthesizing an adjuvant form of lipid A (monophosphoryl lipid A, MPLA) displayed increased biogenesis of bacterial outer membrane vesicles (OMVs). To enhance the immunogenicity of the OMVs, we constructed an Asd-based balanced-lethal host-vector system that oversynthesized the LcrV antigen of Y. pestis, raised the amounts of LcrV enclosed in OMVs by the type II secretion system, and eliminated harmful factors like plasminogen activator (Pla) and murine toxin from the OMVs. Vaccination with OMVs containing MPLA and increased amounts of LcrV with diminished toxicity afforded complete protection in mice against subcutaneous challenge with 8 × 105 CFU (80,000 50% lethal dose [LD50]) and intranasal challenge with 5 × 103 CFU (50 LD50) of virulent Y. pestis. This protection was significantly superior to that resulting from vaccination with LcrV/alhydrogel or rF1-V/alhydrogel. At week 4 postimmunization, the OMV-immunized mice showed more robust titers of antibodies against LcrV, Y. pestis whole-cell lysate (YPL), and F1 antigen and more balanced IgG1:IgG2a/IgG2b-derived Th1 and Th2 responses than LcrV-immunized mice. Moreover, potent adaptive and innate immune responses were stimulated in the OMV-immunized mice. Our findings demonstrate that self-adjuvanting Y. pestis OMVs provide a novel plague vaccine candidate and that the rational design of OMVs could serve as a robust approach for vaccine development.

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Immunomodulatory Effects of Yersinia pestis Lipopolysaccharides on Human Macrophages

Clinical and Vaccine Immunology ◽

10.1128/cvi.00336-09 ◽

2009 ◽

Vol 17 (1) ◽

pp. 49-55 ◽

Cited By ~ 20

Author(s):

Motohiro Matsuura ◽

Hideyuki Takahashi ◽

Haruo Watanabe ◽

Shinji Saito ◽

Kazuyoshi Kawahara

Keyword(s):

Inflammatory Response ◽

Yersinia Pestis ◽

Lipid A ◽

Antagonistic Activity ◽

Gram Negative Bacteria ◽

Toll Like Receptor ◽

Defense System ◽

Toll Like Receptor 4 ◽

Bacterial Binding ◽

Binding Forms

ABSTRACTIn the current study, we investigated the activity of lipopolysaccharide (LPS) purified fromYersinia pestisgrown at either 27°C or 37°C (termed LPS-27 and LPS-37, respectively). LPS-27 containing hexa-acylated lipid A, similar to the LPS present in usual gram-negative bacteria, stimulated an inflammatory response in human U937 cells through Toll-like receptor 4 (TLR4). LPS-37, which did not contain hexa-acylated lipid A, exhibited strong antagonistic activity to the TLR4-mediated inflammatory response. The phagocytic activity in the cells was not affected by LPS-37. To estimate the activity of LPS in its bacterial binding form, formalin-killed bacteria (FKB) were prepared fromY. pestiscells grown at 27°C or 37°C (termed FKB-27 and FKB-37, respectively). FKB-27 strongly stimulated the inflammatory response. This activity was suppressed in the presence of an anti-TLR4 antibody but not an anti-TLR2 antibody. In addition, this activity was almost completely suppressed by LPS-37, indicating that the activity of FKB-27 is predominantly derived from the LPS-27 bacterial binding form. In contrast, FKB-37 showed no antagonistic activity. The results arising from the current study indicate thatY. pestiscauses infection in humans without stimulating the TLR4-based defense systemviabacterial binding of LPS-37, even when bacterial free LPS-37 is not released to suppress the defense system. This is in contrast to the findings for bacteria that possess agonistic LPS types, which are easily recognized by the defense systemviathe bacterial binding forms.

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Yersinia pestis Is Viable with Endotoxin Composed of Only Lipid A

Journal of Bacteriology ◽

10.1128/jb.187.18.6599-6600.2005 ◽

2005 ◽

Vol 187 (18) ◽

pp. 6599-6600 ◽

Cited By ~ 22

Author(s):

Li Tan ◽

Creg Darby

Keyword(s):

Escherichia Coli ◽

Yersinia Pestis ◽

Outer Membrane ◽

Salmonella Enterica ◽

Lipid A ◽

Gram Negative Bacteria ◽

Membrane Component ◽

Gram Negative ◽

Serovar Typhimurium

ABSTRACT Lipopolysaccharide (LPS) is the major outer membrane component of gram-negative bacteria. The minimal LPS structure for viability of Escherichia coli and Salmonella enterica serovar Typhimurium is lipid A glycosylated with 3-deoxy-D-manno-octulosonic acid (Kdo) residues. Here we show that another member of the Enterobacteriaceae, Yersinia pestis, can survive without Kdo in its LPS.

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