-
Indian Journal of Ophthalmology Nov 2020A 33-year-old lady with history of failed keratoplasty for decompensated cornea due to childhood trauma and secondary glaucoma, post glaucoma drainage implant, with...
A 33-year-old lady with history of failed keratoplasty for decompensated cornea due to childhood trauma and secondary glaucoma, post glaucoma drainage implant, with pseudophakia in the right eye, developed bacterial keratitis following foreign body trauma to corneal graft. Corneal cultures yielded Burkholderia cenocepacia identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF- MS, bioMerieux, France). She healed with topical antibiotics (moxifloxacin 0.5%) in 1 month. Ours is the first report of ocular Burkholderia cenocepacia infection, possibly an under reported, aerobic, organism.
Topics: Adult; Anti-Bacterial Agents; Burkholderia cenocepacia; Eye Infections, Bacterial; Female; Humans; Keratitis; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 33120688
DOI: 10.4103/ijo.IJO_1905_20 -
Frontiers in Microbiology 2017is an opportunistic pathogen particularly dangerous for cystic fibrosis (CF) patients. It can cause a severe decline in CF lung function possibly developing into a... (Review)
Review
is an opportunistic pathogen particularly dangerous for cystic fibrosis (CF) patients. It can cause a severe decline in CF lung function possibly developing into a life-threatening systemic infection known as cepacia syndrome. Antibiotic resistance and presence of numerous virulence determinants in the genome make extremely difficult to treat. Better understanding of its resistance profiles and mechanisms is crucial to improve management of these infections. Here, we present the clinical distribution of described in the last 6 years and methods for identification and classification of epidemic strains. We also detail new antibiotics, clinical trials, and alternative approaches reported in the literature in the last 5 years to tackle resistance issue. All together these findings point out the urgent need of new and alternative therapies to improve CF patients' life expectancy.
PubMed: 28878751
DOI: 10.3389/fmicb.2017.01592 -
Microbiology Spectrum Aug 2022Burkholderia cenocepacia is a human opportunistic pathogen that mostly employs two types of quorum-sensing (QS) systems to regulate its various biological functions and...
Burkholderia cenocepacia is a human opportunistic pathogen that mostly employs two types of quorum-sensing (QS) systems to regulate its various biological functions and pathogenicity: the -2-dodecenoic acid (BDSF) system and the -acyl homoserine lactone (AHL) system. In this study, we reported that oridonin, which was screened from a collection of natural products, disrupted important B. cenocepacia phenotypes, including motility, biofilm formation, protease production, and virulence. Genetic and biochemical analyses showed that oridonin inhibited the production of BDSF and AHL signals by decreasing the expression of their synthase-encoding genes. Furthermore, we revealed that oridonin directly binds to the regulator RqpR of the two-component system RqpSR that dominates the above-mentioned QS systems to inhibit the expression of the BDSF and AHL signal synthase-encoding genes. Oridonin also binds to the transcriptional regulator CepR of the AHL system to inhibit its binding to the promoter of . These findings suggest that oridonin could potentially be developed as a new QS inhibitor against pathogenic B. cenocepacia. Burkholderia cenocepacia is an important human opportunistic pathogen that can cause life-threatening infections in susceptible individuals. It employs quorum-sensing (QS) systems to regulate biological functions and virulence. In this study, we have identified a lead compound, oridonin, that is capable of interfering with B. cenocepacia QS signaling and physiology. We demonstrate that oridonin suppressed -2-dodecenoic acid (BDSF) and -acyl homoserine lactone (AHL) signal production and attenuated virulence in B. cenocepacia. Oridonin also impaired QS-regulated phenotypes in various Burkholderia species. These results suggest that oridonin could interfere with QS signaling in many Burkholderia species and might be developed as a new antibacterial agent.
Topics: Acyl-Butyrolactones; Bacterial Proteins; Burkholderia cenocepacia; Diterpenes, Kaurane; Gene Expression Regulation, Bacterial; Humans; Quorum Sensing; Virulence
PubMed: 35856676
DOI: 10.1128/spectrum.01787-22 -
Trends in Microbiology Apr 2020Cystic fibrosis (CF) patients are at particular risk of infection by microorganisms that are resistant to several antibiotics. About 3% of CF patients are colonized by... (Review)
Review
Cystic fibrosis (CF) patients are at particular risk of infection by microorganisms that are resistant to several antibiotics. About 3% of CF patients are colonized by Burkholderia cenocepacia, and this represents a major threat because of its intrinsic high level of drug resistance and the lack of a safe and effective treatment protocol. The development of anti-Burkholderia vaccines is a valuable and complementary approach, but only a few studies have been reported to date. In this review we discuss recent advances in the vaccine field and how new technologies, including structural reverse vaccinology, could drive the design of an effective vaccine against B. cenocepacia for use in preventive and therapeutic applications.
Topics: Animals; Anti-Bacterial Agents; Burkholderia Infections; Burkholderia cenocepacia; Cystic Fibrosis; Drug Resistance, Bacterial; Humans; Lung; Microbiota; Vaccines; Virulence Factors
PubMed: 31932141
DOI: 10.1016/j.tim.2019.12.005 -
Clinical Microbiology and Infection :... Jul 2010Burkholderia cepacia complex (Bcc) bacteria have gained notoriety as pathogens in cystic fibrosis (CF) because they are difficult to identify and treat, and also have... (Review)
Review
Burkholderia cepacia complex (Bcc) bacteria have gained notoriety as pathogens in cystic fibrosis (CF) because they are difficult to identify and treat, and also have the ability to spread between CF individuals. Of the 17 formally named species within the complex, Burkholderia multivorans and Burkholderia cenocepacia dominate in CF. Multilocus sequence typing has proven to be a very useful tool for tracing the global epidemiology of Bcc bacteria and has shown that B. cenocepacia strains with high transmissibility, such as the ET-12 strain (ST-28) and the Czech strain (ST-32), have spread epidemically within CF populations in Canada and Europe. The majority of research on the molecular pathogenesis of Bcc bacteria has focused on the B. cenocepacia ET-12 epidemic lineage, with gene mutation, genome sequence analysis and, most recently, global gene expression studies shedding considerable light on the virulence and antimicrobial resistance of this pathogen. These studies demonstrate that the ability of B. cenocepacia to acquire foreign DNA (genomic islands, insertion sequences and other mobile elements), regulate gene expression via quorum sensing, compete for iron during infection, and mediate antimicrobial resistance and inflammation via its membrane and surface polysaccharides are key features that underpin the virulence of different strains. With the wealth of molecular knowledge acquired in the last decade on B. cenocepacia strains, we are now in a much better position to develop strategies for the treatment of pathogenic colonization with Bcc and to answer key questions on pathogenesis concerning, for example, the factors that trigger the rapid clinical decline in CF patients.
Topics: Burkholderia Infections; Burkholderia cenocepacia; Burkholderia cepacia complex; Canada; Cystic Fibrosis; Drug Resistance, Bacterial; Europe; Gene Expression; Humans; Interspersed Repetitive Sequences; Molecular Epidemiology; Multilocus Sequence Typing; Mutation; Polysaccharides, Bacterial; Quorum Sensing; Respiratory Tract Infections; Virulence
PubMed: 20880411
DOI: 10.1111/j.1469-0691.2010.03237.x -
Applied and Environmental Microbiology Feb 2022It has been demonstrated that quorum sensing (QS) is widely employed by bacterial cells to coordinately regulate various group behaviors. Diffusible signal factor... (Review)
Review
It has been demonstrated that quorum sensing (QS) is widely employed by bacterial cells to coordinately regulate various group behaviors. Diffusible signal factor (DSF)-type signals have emerged as a growing family of conserved cell-cell communication signals. In addition to the DSF signal initially identified in Xanthomonas campestris pv. campestris, iffusible ignal actor (BDSF) (-2-dodecenoic acid) has been recognized as a conserved DSF-type signal with specific characteristics in both signal perception and transduction from DSF signals. Here, we review the history and current progress of the research on this type of signal, especially focusing on its biosynthesis, signaling pathways, and biological functions. We also discuss and explore the huge potential of targeting this kind of QS system as a new therapeutic strategy to control bacterial infections and diseases.
Topics: Bacterial Proteins; Burkholderia; Burkholderia cenocepacia; Fatty Acids, Monounsaturated; Gene Expression Regulation, Bacterial; Quorum Sensing; Suppressor Factors, Immunologic
PubMed: 34985987
DOI: 10.1128/aem.02342-21 -
Frontiers in Cellular and Infection... 2011Burkholderia cenocepacia is an opportunistic respiratory pathogen of individuals with cystic fibrosis (CF). Some strains of B. cenocepacia are highly transmissible and... (Review)
Review
Burkholderia cenocepacia is an opportunistic respiratory pathogen of individuals with cystic fibrosis (CF). Some strains of B. cenocepacia are highly transmissible and resistant to almost all antibiotics. Approximately one-third of B. cenocepacia infected CF patients go on to develop fatal "cepacia syndrome." During the last two decades, substantial progress has been made with regards to evasion of host innate defense mechanisms by B. cenocepacia. Almost all strains of B. cenocepacia have the capacity to survive and replicate intracellularly in both airway epithelial cells and macrophages, which are primary sentinels of the lung and play a pivotal role in clearance of infecting bacteria. Those strains of B. cenocepacia, which express both cable pili and the associated 22 kDa adhesin are also capable of transmigrating across airway epithelium and persist in mouse models of infection. In this review, we will discuss how this type of interaction between B. cenocepacia and host may lead to persistence of bacteria as well as lung inflammation in CF patients.
Topics: Animals; Burkholderia Infections; Burkholderia cenocepacia; Cystic Fibrosis; Cytokines; Disease Models, Animal; Endocytosis; Host-Pathogen Interactions; Humans; Immunity, Innate; Inflammation Mediators; Lung; Mice; Opportunistic Infections; Respiratory Mucosa; Respiratory Tract Infections; Toll-Like Receptors
PubMed: 22919590
DOI: 10.3389/fcimb.2011.00025 -
BMC Microbiology Jan 2023Burkholderia cenocepacia is an opportunistic pathogen that can cause acute and chronic infections in patients with weakened immune systems and in patients with cystic...
BACKGROUND
Burkholderia cenocepacia is an opportunistic pathogen that can cause acute and chronic infections in patients with weakened immune systems and in patients with cystic fibrosis. B. cenocepacia is resistant to many antibiotics making treatment challenging. Consequently, there is a critical need for alternative strategies to treat B. cenocepacia infections such as using bacteriophages and/or bacteriophages with subinhibitory doses of antibiotic called phage-antibiotic synergy.
RESULTS
We isolated a bacteriophage, KP1, from raw sewage that infects B. cenocepacia. Its morphological characteristics indicate it belongs in the family Siphoviridae, it has a 52 Kb ds DNA genome, and it has a narrow host range. We determined it rescued infections in Lemna minor (duckweed) and moderately reduced bacterial populations in our artificial sputum medium model.
CONCLUSION
These results suggest that KP1 phage alone in the duckweed model or in combination with antibiotics in the ASMDM model improves the efficacy of reducing B. cenocepacia populations.
Topics: Humans; Burkholderia cenocepacia; Bacteriophages; Anti-Bacterial Agents; Burkholderia Infections
PubMed: 36600213
DOI: 10.1186/s12866-022-02738-0 -
MicrobiologyOpen Jul 2019Burkholderia cenocepacia is an opportunistic bacterial pathogen that poses a significant threat to individuals with cystic fibrosis by provoking a strong inflammatory...
Burkholderia cenocepacia is an opportunistic bacterial pathogen that poses a significant threat to individuals with cystic fibrosis by provoking a strong inflammatory response within the lung. It possesses a type VI secretion system (T6SS), a secretory apparatus that can perforate the cellular membrane of other bacterial species and/or eukaryotic targets, to deliver an arsenal of effector proteins. The B. cenocepacia T6SS (T6SS-1) has been shown to be implicated in virulence in rats and contributes toward actin rearrangements and inflammasome activation in B. cenocepacia-infected macrophages. Here, we present bioinformatics evidence to suggest that T6SS-1 is the archetype T6SS in the Burkholderia genus. We show that B. cenocepacia T6SS-1 is active under normal laboratory growth conditions and displays antibacterial activity against other Gram-negative bacterial species. Moreover, B. cenocepacia T6SS-1 is not required for virulence in three eukaryotic infection models. Bioinformatics analysis identified several candidate T6SS-dependent effectors that may play a role in the antibacterial activity of B. cenocepacia T6SS-1. We conclude that B. cenocepacia T6SS-1 plays an important role in bacterial competition for this organism, and probably in all Burkholderia species that possess this system, thereby broadening the range of species that utilize the T6SS for this purpose.
PubMed: 30628184
DOI: 10.1002/mbo3.774 -
Virulence Aug 2017
Topics: Burkholderia Infections; Burkholderia cenocepacia; Burkholderia cepacia complex; Cystic Fibrosis; Humans; Lung; Virulence
PubMed: 27786605
DOI: 10.1080/21505594.2016.1253660