Effects of growth rate and nutrient limitation on virulence factor production in Burkholderia cepacia

McKenney, David; Allison, David

doi:10.1128/jb.177.14.4140-4143.1995

Cited by 17 publications

(18 citation statements)

References 40 publications

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“…Several putative virulence factors other than genomovar have been identified: expression of a cable-like pilus,24 interleukin 8 stimulation25 and proinflammatory activity,26 production of haemolytic toxin,27 proteases, 28 siderophores29 and escape from host cell microbicidal activity by means of delayed phagosome maturation 30. The promotion of biofilm development may also increase the resistance and tolerance of BCC to antibiotics 31.…”

Section: Discussionmentioning

confidence: 99%

Clinical outcome following lung transplantation in patients with cystic fibrosis colonised with Burkholderia cepacia complex: results from two French centres

Boussaud

Guillemain

Grenet

et al. 2008

Thorax

107

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Background: Infection with Burkholderia cepacia complex (BCC) is a life threatening complication of cystic fibrosis (CF), often seen as a contraindication for lung transplantation. Methods: A long term retrospective study was conducted of all patients with CF undergoing lung transplants from January 1990 to October 2006 in two French centres allowing transplantation in patients colonised with BCC. Results: 22 of the 247 lung transplant patients with CF were infected with BCC (B cenocepacia genomovar III (n = 8), B multivorans genomovar II (n = 11), B vietnamiensis genomovar V (n = 2) and B stabilis genomovar IV (n = 1)). BCC colonisation was not associated with any significant excess mortality (HR 1.5, 95% CI 0.7 to 3.2; p = 0.58). However, early mortality rates tended to be higher in the BCC group than in the non-BCC group (3 month survival: 85% vs 95%, respectively; log rank p = 0.05). Univariate analysis showed that the risk of death was significantly higher for the eight patients infected with B cenocepacia than for the other 14 colonised patients (HR 3.2, 95% CI 1.1 to 5.9; p = 0.04). None of the other risk factors testedprimary graft failure, late extubation, septicaemia-had a significant effect. The 5 year cumulative incidence rate of bronchiolitis obliterans syndrome was not significantly higher in the BCC group than in the non-BCC group (38% vs 24%, respectively; p = 0.35). Conclusion: Our results suggest that BCC infection with a non-genomovar III organism may not be associated with excess mortality after lung transplantation in patients with CF and should not be seen as sufficient reason to exclude lung transplantation. However, colonisation with B cenocepacia remains potentially detrimental.Cystic fibrosis (CF) is the most common inherited lung disease. It frequently progresses to respiratory failure and death and the treatments currently available aim to slow progression through respiratory therapy, good nutritional support and the treatment of pulmonary exacerbations. In patients with end stage CF, lung transplantation may help to prolong survival and ensure that patients have an acceptable quality of life. Survival rates 1, 3 and 5 years after transplantation of 76%, 60% and 49%, respectively, have been reported. 1 Organ shortages have led some physicians to try to select the ''best candidates'' for lung transplantation.2 One of the criteria used in pretransplantation selection is the absence of infection with Burkholderia cepacia complex (BCC). This gram negative bacterium causes serious opportunistic infections and has emerged as a major pathogen in patients with CF, with the clinical outcome of infection varying from long term bronchial colonisation to life threatening necrotising pneumonia and sepsis, known as ''cepacia syndrome''. Global mortality rates for BCC colonisation may reach 50%, 3-9 depending on genomovar type. However, these rates were determined for patients who had not yet undergone transplantation. Conflicting results have been published concerning post-transplantation ...

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Section: Discussionmentioning

confidence: 99%

Clinical outcome following lung transplantation in patients with cystic fibrosis colonised with Burkholderia cepacia complex: results from two French centres

Boussaud

Guillemain

Grenet

et al. 2008

Thorax

107

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“…Moreover, in high nutrient environments, some bacteria express virulence factors and other pathogenic characteristics (e.g. Brown & Williams, 1985;Kinnela et al, 2017;McKenny & Allison, 1995).…”

Section: Arval O Ce Anog R Aphy and The Pl Ank Ton Communit Ymentioning

confidence: 99%

“…Gallagher et al, 1994;Gosselin & Qian, 1997;Rivkin et al, 1986), making it more likely for larvae to encounter pathogenic or virulent species of microbes (e.g. Azam & Malfatti, 2007;McKenny & Allison, 1995).…”

Section: Arval O Ce Anog R Aphy and The Pl Ank Ton Communit Ymentioning

confidence: 99%

A microbial perspective on the life‐history evolution of marine invertebrate larvae: If, where and when to feed

2018

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The feeding environment for planktotrophic larvae has a major impact on development and progression towards competency for metamorphosis. High phytoplankton environments that promote growth and development also correlate with a greater abundance of environmental microbes and incidence of pathogenic microbes, making these habitats potentially risky for larvae. Trade‐offs between metabolic processes for growth and immune functionality have been described throughout the animal kingdom and may influence the life‐history evolution of marine invertebrate planktotrophic larvae. Specifically, larvae would be predicted to regulate time spent between these feeding environments to avoid potential incidences of microbial‐mediated mortality and/or dysbiosis. Using transcriptomic and microbiome data, we provide evidence for this trade‐off in larvae of the sea urchin Strongylocentrotus droebachiensis. When cultured in a well‐fed environment, larvae upregulate genes associated with metabolism while decreasing the expression of genes associated with immune function. At the same time, the associated bacterial community shifts towards a state of dysbiosis that is followed by mortality. To test whether the environmental microbiota is a selective force on if, where and when planktotrophic larvae should feed, we conclude by presenting a strategy for determining the specific interactions of larvae and microbes at a scale representative of their pelagic environment.

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“…Although it has now emerged as an important aetiological agent in nosocomial infection, B. cepacia is now ‘considered a particularly problematic pathogen in patients with fibrocystic lung disease owing to its increasing association with fatal pulmonary infections’ [10]. The lipase from B. cepacia is considered a virulence factor and is regulated differently from other virulence factors [10]. The pathogenesis of pulmonary infections in cystic fibrosis patients is not completely understood and any molecular characterization of virulence factors would be of obvious importance in understanding the clinical picture [11].…”

Section: Introductionmentioning

confidence: 99%

Purification and properties of the alkaline lipase from Burkholderia cepacia A.T.C.C. 25609

Dalal

Singh

Raghava

et al. 2008

Biotech and App Biochem

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A Burkholderia cepacia (bacteria) strain, A.T.C.C. 25609, which had been isolated from the bronchial washings of a cystic fibrosis patient, was used to produce lipase. The presence of sodium alginate at an optimal concentration of 8 mg.ml(-1) in the growth medium nearly doubled the production of extracellular lipase activity. The enzyme could be purified with 38-fold purification and 96% activity recovery using a two-step purification protocol. The molecular mass of the purified lipase determined by SDS/PAGE was shown to be 28 kDa. The pH optimum of the purified enzyme was 9 and it was stable up to 12 h at pH 9 and 10. The enzyme has a temperature optimum of 40 degrees C and its half-life (t(1/2)) values were 54 and 46 min at 50 and 60 degrees C respectively. The lipase was found to be stable in the presence of the detergents Tween 20 and Triton X-100. The secondary-structure analysis of lipase by CD spectroscopy showed 52% alpha-helix, 7.7% beta-sheet, 12.6% beta-turn and 27.8% random structure. The lipase was cloned and overexpressed in Escherichia coli. The gene sequence of the cloned lipase was determined and compared with other lipases.

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Effects of growth rate and nutrient limitation on virulence factor production in Burkholderia cepacia

Cited by 17 publications

References 40 publications

Clinical outcome following lung transplantation in patients with cystic fibrosis colonised with Burkholderia cepacia complex: results from two French centres

Clinical outcome following lung transplantation in patients with cystic fibrosis colonised with Burkholderia cepacia complex: results from two French centres

A microbial perspective on the life‐history evolution of marine invertebrate larvae: If, where and when to feed

Purification and properties of the alkaline lipase from Burkholderia cepacia A.T.C.C. 25609

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