Burkholderia gladioli
Encyclopedia
Burkholderia gladioli is a species of aerobic
gram-negative
rod-shaped
bacteria
that causes disease in both humans and plants. It can also live in symbiosis
with plants and fungi and is found in soil, water, the rhizosphere, and in many animals. It was formerly known as Pseudomonas marginata.
were formally classified as Pseudomonas, but Burkholderia was one of the seven genera that arose when Pseudomonas was divided based on rRNA differences. Burkholderia gladioli is closely related to, and often mistaken for, a member of the Burkholderia cepacia complex
. This includes ten closely related species, which are all plant pathogens.
Burkholderia gladioli is divided into three pathovars: gladioli, allicola, and agaricicola. B. gladioli pv. gladioli causes gladiolus rot, allicola causes onion bulb rot, and agaricicola causes soft rot in mushrooms
, but do not ferment the lactose. Burkholderia gladioli can be distinguished from the other Burkholderia because it is oxidase negative B. gladioli is indole negative, nitrate negative, and lysine decorboxylation negative
On the molecular level, PCR can be used to distinguish between the different Burkholderia species. According to Furuya et al., the ribosomal RNA gene is highly conserved and universally distributed in all living things, and therefore difference in the DNA sequences between 16S and 23S rRNA genes can be used to differentiate between the species.
The primers used for the amplification of the 16S to 23S region in the B. gladioli genome are as follows: GLA-f 5'-(CGAGCTAATACCGCGAAA)-3' and GLA-r 5'-(AGACTCGAGTCAACTGA)-3' Using these primers for PCR results in an amplicon of approximately 300bp.
All members of the Burkholderia genus have multireplicon genomes. They are able to keep "essential housekeeping" genes on the largest chromosome This largest chromosome has a single origin of replication. The gene order and GC composition is conserved as well. Members of the Burkholderia genus are able to capture and retain foreign DNA. The foreign DNA can be detected by looking for atypical GC context areas. One of the first foreign DNA segments ditected this way encoded for virulence.
Burkholderia gladioli has been identified as a plant pathogen in onion
s, gladiolus
, iris
, and rice
. It was originally described to have caused rot of gladiolus corms. The bulbs can become water soaked and decay.
Some other common symptoms of infected plants can be seen in the leaves. The leaves contain brown legions, and they may become watersoaked. Other symptoms are the wilting and/or rot of roots, stems, and petals. B. gladioli has also been identified as the causative agent in leaf-sheath browning in gladiolas and onions. Sometimes, the whole plant decays.
One widespread plant disease caused by Burkholderia gladioli is called scab. It can be seen on Gladiolus corms as water-soaked brown spots, outlined in yellow. Eventually, they can become hollow and surrounded by scabs. If the scabs fall off, they leave behind cavities or lesions.
that is an important agent for hospital-associated infections. It has recently appeared as a severe pathogen in patients with cystic fibrosis
, causing severe pulmonary infections. Though it is still a fairly uncommon pathogen, its presence is associated with a poor prognosis
. It has also colonized the respiratory tracts of patients with granulomatous disease. In lung transplant
patients, infection can be fatal as patients have developed bacteremia
and sterile wound infections as a result.
Tempe bongkrèk, a variation of tempeh
prepared with coconut, is susceptible to B. gladioli contamination. Contaminated tempe bongkrèk can contain lethal amounts of highly toxic bongkrek acid
and toxoflavin
.
Aerobic organism
An aerobic organism or aerobe is an organism that can survive and grow in an oxygenated environment.Faculitative anaerobes grow and survive in an oxygenated environment and so do aerotolerant anaerobes.-Glucose:...
gram-negative
Gram-negative
Gram-negative bacteria are bacteria that do not retain crystal violet dye in the Gram staining protocol. In a Gram stain test, a counterstain is added after the crystal violet, coloring all Gram-negative bacteria with a red or pink color...
rod-shaped
Bacillus (shape)
The word bacillus may be used to describe any rod-shaped bacterium, and such bacilli are found in many different taxonomic groups of bacteria. However, the name Bacillus, capitalized and italicized, refers to a specific genus of bacteria...
bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
that causes disease in both humans and plants. It can also live in symbiosis
Symbiosis
Symbiosis is close and often long-term interaction between different biological species. In 1877 Bennett used the word symbiosis to describe the mutualistic relationship in lichens...
with plants and fungi and is found in soil, water, the rhizosphere, and in many animals. It was formerly known as Pseudomonas marginata.
Nomenclature
The members of the genus BurkholderiaBurkholderia
Burkholderia is a genus of proteobacteria probably best known for its pathogenic members:Burkholderia mallei, responsible for glanders, a disease that occurs mostly in horses and related animals;...
were formally classified as Pseudomonas, but Burkholderia was one of the seven genera that arose when Pseudomonas was divided based on rRNA differences. Burkholderia gladioli is closely related to, and often mistaken for, a member of the Burkholderia cepacia complex
Burkholderia cepacia complex
Burkholderia cepacia complex , or simply Burkholderia cepacia is a group of catalase-producing, non-lactose-fermenting Gram-negative bacteria composed of at least seventeen different species, including B. cepacia, B. multivorans, B. cenocepacia, B. vietnamiensis, B. stabilis, B. ambifaria, B....
. This includes ten closely related species, which are all plant pathogens.
Burkholderia gladioli is divided into three pathovars: gladioli, allicola, and agaricicola. B. gladioli pv. gladioli causes gladiolus rot, allicola causes onion bulb rot, and agaricicola causes soft rot in mushrooms
Identification
Burkholderia are motile, Gram negative rods that may be straight or slightly curved. They are aerobic, catalase positive, urease positive, nonsporeformers. They grow on MacConkey agarMacConkey agar
MacConkey agar is a culture medium designed to grow Gram-negative bacteria and stain them for lactose fermentation.-Contents:It contains bile salts MacConkey agar is a culture medium designed to grow Gram-negative bacteria and stain them for lactose fermentation.-Contents:It contains bile salts...
, but do not ferment the lactose. Burkholderia gladioli can be distinguished from the other Burkholderia because it is oxidase negative B. gladioli is indole negative, nitrate negative, and lysine decorboxylation negative
On the molecular level, PCR can be used to distinguish between the different Burkholderia species. According to Furuya et al., the ribosomal RNA gene is highly conserved and universally distributed in all living things, and therefore difference in the DNA sequences between 16S and 23S rRNA genes can be used to differentiate between the species.
The primers used for the amplification of the 16S to 23S region in the B. gladioli genome are as follows: GLA-f 5'-(CGAGCTAATACCGCGAAA)-3' and GLA-r 5'-(AGACTCGAGTCAACTGA)-3' Using these primers for PCR results in an amplicon of approximately 300bp.
All members of the Burkholderia genus have multireplicon genomes. They are able to keep "essential housekeeping" genes on the largest chromosome This largest chromosome has a single origin of replication. The gene order and GC composition is conserved as well. Members of the Burkholderia genus are able to capture and retain foreign DNA. The foreign DNA can be detected by looking for atypical GC context areas. One of the first foreign DNA segments ditected this way encoded for virulence.
In plants
Onion
The onion , also known as the bulb onion, common onion and garden onion, is the most widely cultivated species of the genus Allium. The genus Allium also contains a number of other species variously referred to as onions and cultivated for food, such as the Japanese bunching onion The onion...
s, gladiolus
Gladiolus
Gladiolus is a genus of perennial bulbous flowering plants in the iris family...
, iris
Iris (plant)
Iris is a genus of 260-300species of flowering plants with showy flowers. It takes its name from the Greek word for a rainbow, referring to the wide variety of flower colors found among the many species...
, and rice
Rice
Rice is the seed of the monocot plants Oryza sativa or Oryza glaberrima . As a cereal grain, it is the most important staple food for a large part of the world's human population, especially in East Asia, Southeast Asia, South Asia, the Middle East, and the West Indies...
. It was originally described to have caused rot of gladiolus corms. The bulbs can become water soaked and decay.
Some other common symptoms of infected plants can be seen in the leaves. The leaves contain brown legions, and they may become watersoaked. Other symptoms are the wilting and/or rot of roots, stems, and petals. B. gladioli has also been identified as the causative agent in leaf-sheath browning in gladiolas and onions. Sometimes, the whole plant decays.
One widespread plant disease caused by Burkholderia gladioli is called scab. It can be seen on Gladiolus corms as water-soaked brown spots, outlined in yellow. Eventually, they can become hollow and surrounded by scabs. If the scabs fall off, they leave behind cavities or lesions.
In humans
Burkholderia gladioli in humans is an opportunistic pathogenOpportunistic infection
An opportunistic infection is an infection caused by pathogens, particularly opportunistic pathogens—those that take advantage of certain situations—such as bacterial, viral, fungal or protozoan infections that usually do not cause disease in a healthy host, one with a healthy immune system...
that is an important agent for hospital-associated infections. It has recently appeared as a severe pathogen in patients with cystic fibrosis
Cystic fibrosis
Cystic fibrosis is a recessive genetic disease affecting most critically the lungs, and also the pancreas, liver, and intestine...
, causing severe pulmonary infections. Though it is still a fairly uncommon pathogen, its presence is associated with a poor prognosis
Prognosis
Prognosis is a medical term to describe the likely outcome of an illness.When applied to large statistical populations, prognostic estimates can be very accurate: for example the statement "45% of patients with severe septic shock will die within 28 days" can be made with some confidence, because...
. It has also colonized the respiratory tracts of patients with granulomatous disease. In lung transplant
Organ transplant
Organ transplantation is the moving of an organ from one body to another or from a donor site on the patient's own body, for the purpose of replacing the recipient's damaged or absent organ. The emerging field of regenerative medicine is allowing scientists and engineers to create organs to be...
patients, infection can be fatal as patients have developed bacteremia
Bacteremia
Bacteremia is the presence of bacteria in the blood. The blood is normally a sterile environment, so the detection of bacteria in the blood is always abnormal....
and sterile wound infections as a result.
Tempe bongkrèk, a variation of tempeh
Tempeh
Tempeh , or tempe , is a traditional soy product originally from Indonesia. It is made by a natural culturing and controlled fermentation process that binds soybeans into a cake form, similar to a very firm vegetarian burger patty...
prepared with coconut, is susceptible to B. gladioli contamination. Contaminated tempe bongkrèk can contain lethal amounts of highly toxic bongkrek acid
Bongkrek acid
Bongkrek acid is a respiratory toxin more deadly than other mitochondrial poisons cyanide or 2,4-dinitrophenol. There was some dispute regarding the actual structure of bongkrek acid but this was resolved in 1973, which explains different structures appearing in the literature prior to this...
and toxoflavin
Toxoflavin
Toxoflavin is a toxin produced by a variety of bacteria including Burkholderia gladioli. It also has antibiotic properties.Toxoflavin acts as a pH indicator, changing between yellow and colorless at pH 10.5....
.