Burkholderia cenocepacia

Burkholderia cenocepacia
Electron micrograph of Burkholeria cepacia
Scientific classification
Domain:	Bacteria
Phylum:	Proteobacteria
Class:	Betaproteobacteria
Order:	Burkholderiales
Family:	Burkholderiaceae
Genus:	Burkholderia
Species:	B. cenocepacia
Binomial name
Burkholderia cenocepacia Vandamme et al. 2003

Burkholderia cenocepacia is a species of Gram-negative bacteria that is common in the environment, can form a biofilm with itself,^[1] is resistant to many antibiotics^[2] and may cause disease in plants.

Pathogenicity[]

It is an opportunistic pathogen and human infections are common in patients with cystic fibrosis and chronic granulomatous disease, and are often fatal.^[3] In cystic fibrosis, it can cause "cepacia syndrome" which is characterized by a rapidly progressive fever, uncontrolled bronchopneumonia, weight loss, and in some cases, death. A review of B. cenocepacia in respiratory infections of cystic fibrosis patients stated that "one of the most threatening pathogens in [cystic fibrosis] is Burkholderia cenocepacia, a member of a bacterial group collectively referred to as the Burkholderia cepacia complex (Bcc)".^[4] Twenty-four Small RNAs were identified using RNA binding properties of the Hfq protein during the exponential growth phases.^[5] sRNAs identified in Burkholderia cenocepacia KC-0 were upregulated under iron depletion and oxidate stress.^[6] In Seattle, a team led by microbiologist Joseph Mougous at the University of Washington had discovered a strange enzyme (a toxin called ) made by the bacterium Burkholderia cenocepacia — and when it encountered the DNA base C, it converted it to a U. Because U, which is not commonly found in DNA, behaves like a T, the enzymes that replicate the cell’s DNA copy it as a T, effectively converting a C in the genome sequence to a T. This has reportedly been used for the first gene-editing of mitochondria – for which a team at the Broad Institute developed a new kind of CRISPR-free base editor, called DdCBE, using the toxin.^{[7][8][9][10]}

See also: Burkholderia thailandensis sRNA

Taxonomy[]

Originally defined as B. cepacia, the group has now been split into nine species,^[11] and B. cenocepacia is one of the most intensively-studied.^[12]

Microbiology[]

In addition, the strong environmental protection response of B. cenocepacia is attributed to the biofilm formed by groups of the organism.^[2] This biofilm contains exopolysaccharides (abbreviated EPS) that strengthen the bacterium's resistance to antibiotics. It is made up of a highly branched polysaccharide unit with one glucose, one glucuronic acid, one mannose, one rhamnose, and three galactose molecules. This species in the Bcc has also created another polysaccharide with one 3-deoxy-d-manno-2-octulosonic acid and three galactose molecules.^[13] The biofilm exopolysaccharides acted as a barrier to neutrophils from human immune resistance systems, undermining the neutrophil defense action by inhibiting chemotaxis and reducing the production of reactive oxygen species.^[14]

References[]

External links[]

• "Burkholderia cenocepacia". NCBI Taxonomy Browser. 95486.
• Type strain of Burkholderia cenocepacia at BacDive - the Bacterial Diversity Metadatabase