Genetic organisation of the lipopolysaccharide O-antigen biosynthesis region of   16M ( )

Godfroid, Fabrice; Cloeckaert, Axel; Taminiau, Bernard; Danese, Isabelle; Tibor, Anne; Bolle, Xavier De; Mertens, Pascal; Letesson, Jean‐Jacques

doi:10.1016/s0923-2508(00)90130-x

Cited by 91 publications

(117 citation statements)

References 64 publications

Supporting

Mentioning

113

Contrasting

Order By: Relevance

“…The synthesis of LPS in Brucella is largely unknown but the genetic evidence available [31,51,96] is fully consistent with a mechanism similar to that existing in some of the best studied gram-negative bacteria [54,64,104]. First, lipid A is synthesized on the inner face of the cytoplasmic membrane.…”

Section: Structure Biosynthesis and Genetics Of Brucella S-lpsmentioning

confidence: 70%

“…The B. abortus 45/20 and RB51 strains were developed in this way [75,112]. Alternatively, R mutants can be generated by Molecular Genetics methods such as transposon mutagenesis or deletion of genes involved in S-LPS biosynthesis [3,50,51,76,78,126,135].…”

Section: Brucella Rough (R) Mutantsmentioning

confidence: 99%

“…On the contrary, the O-PS is synthesized in an independent pathway and, once its biosynthesis is carried through, it is linked to the acceptor sugar of the completed lipid A-core. Depending on the particular O-PS, there are three known types of mechanisms of synthesis, and that of Brucella belongs to the so-called ABC transporter-dependent (or wzy-independent) type [51,64]. In this pathway (Fig.…”

Section: Structure Biosynthesis and Genetics Of Brucella S-lpsmentioning

confidence: 99%

See 2 more Smart Citations

Rough vaccines in animal brucellosis: Structural and genetic basis and present status

Grilló²,

et al. 2004

View full text Add to dashboard Cite

-Brucellosis control and eradication requires serological tests and vaccines. Effective classical vaccines (S19 in cattle and Rev 1 in small ruminants), however, induce antibodies to the O-polysaccharide of the lipopolysaccharide which may be difficult to distinguish from those resulting from infection and may thus complicate diagnosis. Rough attenuated mutants lack the O-polysaccharide and would solve this problem if eliciting protective immunity; the empirically obtained rough mutants 45/20 and RB51 have been used as vaccines. Strain 45/20 is reportedly unstable and it is not presently used. RB51 is increasingly used instead of S19 in some countries but it is rifampicin resistant and its effectiveness is controversial. Some controlled experiments have found good or absolute protection in adult cattle vaccinated orally (full dose) or subcutaneously (reduced dose) and in one field experiment, RB51 was reported to afford absolute protection to calves and to perform better than S19. Controlled experiments in calves, however, have shown reduced doses of RB51 to be ineffective, full doses only partially effective, and RB51 less effective than S19 against severe challenges. Moreover, other observations suggest that RB51 is ineffective when prevalence is high. RB51 is not useful in sheep and evidence in goats is preliminary and contradictory. Rough mutants obtained by molecular biology methods on the knowledge of the genetics and structure of Brucella lipopolysaccharide may offer alternatives. The B. abortus manB core (rfbK) mutant seems promising in cattle, and analyses in mice suggest that mutations affecting only the O-polysaccharide result in better vaccines than those affecting both core and O-polysaccharide. Possible uses of rough vaccines also include boosting immunity by revaccination but solid evidence on its effectiveness, safety and practicality is not available.

show abstract

Section: Structure Biosynthesis and Genetics Of Brucella S-lpsmentioning

confidence: 70%

Section: Brucella Rough (R) Mutantsmentioning

confidence: 99%

Section: Structure Biosynthesis and Genetics Of Brucella S-lpsmentioning

confidence: 99%

See 1 more Smart Citation

Rough vaccines in animal brucellosis: Structural and genetic basis and present status

Grilló²,

et al. 2004

View full text Add to dashboard Cite

show abstract

“…Although the two species Brucella ovis and Brucella canis are naturally rough and respectively infect rams and dogs, it has been shown that rough mutants from other species are avirulent (43,44). Among the attenuated mutants, five were affected in genes required at different stages of the lipopolysaccharide biosynthesis (Table 1).…”

Section: Role Of Smooth Lipopolysaccharide In Intracellular Multiplicmentioning

confidence: 99%

The analysis of the intramacrophagic virulome ofBrucella suisdeciphers the environment encountered by the pathogen inside the macrophage host cell

Köhler

Foulongne

Ouahrani‐Bettache

et al. 2002

Proc. Natl. Acad. Sci. U.S.A.

235

234

View full text Add to dashboard Cite

The pathogen Brucella suis resides and multiplies within a phagocytic vacuole of its host cell, the macrophage. The resulting complex relationship has been investigated by the analysis of the set of genes required for virulence, which we call intramacrophagic virulome. Ten thousand two hundred and seventy-two miniTn5 mutants of B. suis constitutively expressing gfp were screened by fluorescence microscopy for lack of intracellular multiplication in human macrophages. One hundred thirty-one such mutants affected in 59 different genes could be isolated, and a function was ascribed to 53 of them. We identified genes involved in (i) global adaptation to the intracellular environment, (ii) amino acid, and (iii) nucleotide synthesis, (iv) sugar metabolism, (v) oxidoreduction, (vi) nitrogen metabolism, (vii) regulation, (viii) disulphide bond formation, and (ix) lipopolysaccharide biosynthesis. Results led to the conclusion that the replicative compartment of B. suis is poor in nutrients and characterized by low oxygen tension, and that nitrate may be used for anaerobic respiration. Intramacrophagic virulome analysis hence allowed the description of the nature of the replicative vacuole of the pathogen in the macrophage and extended our understanding of the niche in which B. suis resides. We propose calling this specific compartment ''brucellosome.'' I nteractions between microorganisms and their hosts extend from acute infections to persistent infectious diseases or symbiosis. This type of interaction can result from a million years of coevolution and coadaptation of the two organisms. Thus, the biology of the interaction can be read, at least partially, in the genome of the microorganism. In the specific case of pathogenic bacteria, deciphering of the genes involved in the interaction and analysis of their functions will shed light on the environment encountered by the parasite in the host and will contribute to the understanding of the complex relationship between two organisms. As a name for the whole set of genes required for virulence, i.e., involved in the invasion of the host by the bacteria and their adaptation to the environment provided by this host, we propose virulome. In this study, we will perform a thorough analysis of the intramacrophagic virulome of Brucella suis.Brucella spp. is an ␣ proteobacteriaceae that induces a persistent disease in some mammals, resulting in abortion. In humans, initial septicemia may be followed by a subacute or a chronic infection (1). Brucella spp. is phyletically related as well to plant symbionts such as rhizobiaceae, as to rickettsiae, which generate an acute infectious disease (2). In terms of virulence, brucellae occupy an intermediate position where the adaptation results in a mild disease that allows them to persist in mammal hosts. It is usually considered that, for a facultative intracellular bacterium such as Brucella spp., which multiplies in trophoblasts or macrophages (3), one of the challenges is to rapidly adapt to the intracellular settings but also to resis...

show abstract

“…The DcstA mutant strain does not lack O antigen and has no detectable core defect. (a) A dot blot was performed with a mAb against the O antigen (A76-12G12) on total extracts of the B. abortus wild-type strain, DcstA strain and, as the negative control, the B. melitensis B3B2 rough mutant (Godfroid et al, 1998). The A76-12G12 antibody equally recognizes B. abortus and B. melitensis strains (Cloeckaert et al, 1993a).…”

Section: Intracellular Trafficking Of the B Abortus Csta Mutant Is Amentioning

confidence: 99%

A Brucella abortus cstA mutant is defective for association with endoplasmic reticulum exit sites and displays altered trafficking in HeLa cells

et al. 2012

Self Cite

View full text Add to dashboard Cite

Genetic organisation of the lipopolysaccharide O-antigen biosynthesis region of 16M ( )

Cited by 91 publications

References 64 publications

Rough vaccines in animal brucellosis: Structural and genetic basis and present status

Rough vaccines in animal brucellosis: Structural and genetic basis and present status

The analysis of the intramacrophagic virulome ofBrucella suisdeciphers the environment encountered by the pathogen inside the macrophage host cell

A Brucella abortus cstA mutant is defective for association with endoplasmic reticulum exit sites and displays altered trafficking in HeLa cells

Contact Info

Product

Resources

About