Two different mechanisms of serum resistance in Escherichia coli

Kubens, Britta S.; Wettstein, Mathias; Opferkuch, W.

doi:10.1016/0882-4010(88)90037-x

Cited by 10 publications

(7 citation statements)

References 29 publications

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“…In 2005, Meri and colleagues [ 40 ] showed that FH maintains its regulatory activity when bound to pathogenic leptospires, but does not bind to saprophytic leptospires. A variety of pathogens bind to complement inhibitors to evade complement system activation: relapsing fever spirochete Borrelia recurrentis binds to FH [ 41 ], C4BP [ 41 ] and C1 inhibitor [ 42 ] and Neisseria gonorrhoeae [ 43 – 44 ], Streptococcus pyogenes [ 45 – 46 ], Haemophilus influenza [ 47 – 48 ], Moraxella catarrhalis [ 49 – 50 ], Bordetella pertussis [ 51 – 52 ], Escherichia coli [ 53 – 54 ] and Pasteurella pneumotropica [ 55 ] interact with C4BP and FH. Not only bacteria, but also fungi have been shown to interact with C4BP, for example, Candida albicans [ 56 ] and Aspergillus [ 57 ].…”

Section: Discussionmentioning

confidence: 99%

Fine Mapping of the Interaction between C4b-Binding Protein and Outer Membrane Proteins LigA and LigB of Pathogenic Leptospira interrogans

et al. 2015

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The complement system consists of more than 40 proteins that participate in the inflammatory response and in pathogen killing. Complement inhibitors are necessary to avoid the excessive consumption and activation of this system on host cells. Leptospirosis is a worldwide zoonosis caused by spirochetes from the genus Leptospira. Pathogenic leptospires are able to escape from complement activation by binding to host complement inhibitors Factor H [FH] and C4b-binding protein (C4BP) while non-pathogenic leptospires are rapidly killed in the presence of fresh serum. In this study, we demonstrate that complement control protein domains (CCP) 7 and 8 of C4BP α-chain interact with the outer membrane proteins LcpA, LigA and LigB from the pathogenic leptospire L. interrogans. The interaction between C4BP and LcpA, LigA and LigB is sensitive to ionic strength and inhibited by heparin. We fine mapped the LigA and LigB domains involved in its binding to C4BP and heparin and found that both interactions are mediated through the bacterial immunoglobulin-like (Big) domains 7 and 8 (LigA7-8 and LigB7-8) of both LigA and LigB and also through LigB9-10. Therefore, C4BP and heparin may share the same binding sites on Lig proteins.

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Section: Discussionmentioning

confidence: 99%

Fine Mapping of the Interaction between C4b-Binding Protein and Outer Membrane Proteins LigA and LigB of Pathogenic Leptospira interrogans

et al. 2015

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“…Cells were grown in 400-ml volumes of Mueller-Hinton broth to the late-exponential phase (8 x 108 cells per ml), centrifuged, and suspended in 3 ml of distilled water. The cells were disrupted by sonication, and unbroken cells were removed by centrifugation (3,000 x g, 15 min, 4°C). The resulting supernatant was centrifuged (130,000 x g, 60 min, 4°C), and the pellet was suspended in 500 ,ul of distilled water.…”

Section: Methodsmentioning

confidence: 99%

“…Serum resistance is an important determinant of the pathogenicity of gram-negative bacteria. Mechanisms of bacterial evasion of complement-mediated killing include early release of generated membrane attack complexes mediated by lipopolysaccharides (LPS) (12), insertion of membrane attack complexes into nonlethal targets of the bacterial cell envelope, possibly directed by certain outer membrane (OM) proteins (8), and interference of certain capsular polysaccharides with alternative-pathway complement activation (10,15; for a review, see reference 11).…”

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confidence: 99%

The capsular polysaccharide is a major determinant of serum resistance in K-1-positive blood culture isolates of Escherichia coli

et al. 1990

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Serum resistance is a major virulence factor of gram-negative bacteria, and K-1 polysaccharide has been shown to contribute to serum resistance in selected strains. To obtain further information about the role of K-1 in serum resistance and to find out whether loss of the ability to produce K-1 can induce loss of serum resistance, we studied the serum resistance of mutants derived from completely serum-resistant, K-i-positive blood culture isolates ofEscherichia coli by selection for resistance to infection with K-1 specific bacteriophages. The amounts of K-1 polysaccharide produced by wild-type strains and mutants were measured, and outer membrane protein and lipopolysaccharide (LPS) patterns were analyzed. In each group of mutants, several highly serum-sensitive strains were found. All mutant strains expressed less K-1 than did the corresponding wild-type strains. Mutants that became highly serum sensitive always had less K-1 than did mutants with less-pronounced changes of serum resistance. A few mutants derived from different wild-type strains showed increased expression of outer membrane proteins with molecular weights of about 46,000 and 67,000. All of the wild-type strains examined had smooth-type LPS, and only two mutants had altered LPS structures; alterations of mutants in outer membrane proteins and LPS could not be correlated with alterations of serum resistance. The results indicate that for K-i-positive blood culture strains of E. coli, K-1 expression is a prerequisite for serum resistance, and loss of ability to synthesize K-1 leads to loss of serum resistance.

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“…In resistant strains, the C5b-8 complex was found intact in the supernatant, shed without C9 binding [48,72,73]. In sensitive, lysed organisms, the MAC was found intact on the outer membrane surface.…”

Section: Resistance To Lysismentioning

confidence: 99%

Complement resistance in microbes

1994

Springer Semin Immunopathol

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Two different mechanisms of serum resistance in Escherichia coli

Cited by 10 publications

References 29 publications

Fine Mapping of the Interaction between C4b-Binding Protein and Outer Membrane Proteins LigA and LigB of Pathogenic Leptospira interrogans

Fine Mapping of the Interaction between C4b-Binding Protein and Outer Membrane Proteins LigA and LigB of Pathogenic Leptospira interrogans

The capsular polysaccharide is a major determinant of serum resistance in K-1-positive blood culture isolates of Escherichia coli

Complement resistance in microbes

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