Burkholderia pseudomallei, the causative agent of melioidosis, is endemic to Southeast Asia and northern Australia. Clinical manifestations of disease are diverse, ranging from chronic infection to acute septicaemia. The current gold standard of diagnosis involves bacterial culture and identification which is time consuming and often too late for early medical intervention. Hence, rapid diagnosis of melioidosis is crucial for the successful management of melioidosis. The study evaluated 4 purified B. pseudomallei recombinant proteins (TssD-5, Omp3, smBpF4 and Omp85) as potential diagnostic agents for melioidosis. A total of 68 sera samples from Malaysian melioidosis patients were screened for the presence of specific antibodies towards these proteins using enzyme-linked immunosorbent assay (ELISA). Sera from patients with various bacterial and viral infections but negative for B. pseudomallei, as well as sera from healthy individuals, were also included as non-melioidosis controls. The Mann Whitney
Looking for Pseudomonas pseudomallei? Find out information about Pseudomonas pseudomallei. A bacteria that is the causative agent of melioidosis, an endemic glanders-like disease of humans and animals that occurs most frequently in southeastern... Explanation of Pseudomonas pseudomallei
BACKGROUND:Melioidosis is an infectious disease that is transmitted mainly through contact with contaminated soil or water, and exhibits marked seasonality in most settings, including Southeast Asia. In this study, we used mathematical modelling to examine the impacts of such demographic changes on melioidosis incidence, and to predict the disease burden in a developing country such as Thailand. METHODOLOGY/PRINCIPAL FINDINGS:A melioidosis infection model was constructed which included demographic data, diabetes mellitus (DM) prevalence, and melioidosis disease processes. The model was fitted to reported melioidosis incidence in Thailand by age, sex, and geographical area, between 2008 and 2015, using a Bayesian Markov Chain Monte Carlo (MCMC) approach. The model was then used to predict the disease burden and future trends of melioidosis incidence in Thailand. Our model predicted two-fold higher incidence rates of melioidosis compared with national surveillance data from 2015. The estimated incidence
Author summary In spite of the fact that Cambodia shares borders with well-known hyper-endemic areas for Burkholderia pseudomallei where thousands of melioidosis cases occur each year, only a handful of melioidosis cases have been described in Cambodia. This is due, in part, to the lack of appropriate diagnostic resources there and the fact that physicians are not familiar with the appropriate diagnostic and treatment algorithms. As a result, the true burden of melioidosis in Cambodia is drastically underestimated and confirmed cases are rarely treated properly. During a one year study of sepsis in Takeo Provincial Hospital in Takeo Province Cambodia, we enrolled 139 patients which included seven culture-confirmed cases of melioidosis. As part of our study, laboratory workups including blood gasses, blood chemistries and hematology are routinely performed as well as imaging and a detailed record of medications administered during treatment. As a result, our report describes one of the more well
Author summary In spite of the fact that Cambodia shares borders with well-known hyper-endemic areas for Burkholderia pseudomallei where thousands of melioidosis cases occur each year, only a handful of melioidosis cases have been described in Cambodia. This is due, in part, to the lack of appropriate diagnostic resources there and the fact that physicians are not familiar with the appropriate diagnostic and treatment algorithms. As a result, the true burden of melioidosis in Cambodia is drastically underestimated and confirmed cases are rarely treated properly. During a one year study of sepsis in Takeo Provincial Hospital in Takeo Province Cambodia, we enrolled 139 patients which included seven culture-confirmed cases of melioidosis. As part of our study, laboratory workups including blood gasses, blood chemistries and hematology are routinely performed as well as imaging and a detailed record of medications administered during treatment. As a result, our report describes one of the more well
Abstract An enzyme-linked immunosorbent assay using a fluorescein isothiocyanate (FITC)-anti-FITC amplification system, has been developed to detect Pseudomonas pseudomallei antigen in urine. The assay was evaluated in 135 patients with acute melioidosis, 194 hospitalized patients with other disorders, and 40 healthy controls. Antigen was detected in the urine of 123 (91%) patients with melioidosis. Urinary antigen was found in 85 (96%) of 89 patients with septicemic melioidosis, all six patients with P. pseudomallei urinary tract infection, and 32 (80%) of 40 patients with other localized infections. Antigen was not detected in the urine of 40 healthy individuals, but the urine of 16 (8%) of 194 hospitalized patients with diagnoses other than melioidosis gave a positive results. Of the false-positive results, 13 of 16 were associated with bacteriuria ≥ 104 colony-forming units/ml. At a cutoff titer of 1:10, the sensitivity and specificity of the test were 81% and 96%, respectively. Enzyme immunoassay
TY - CHAP. T1 - Management of patients with severe melioidosis in intensive care. AU - West, T Eoin. AU - Cheng, Allen. PY - 2012. Y1 - 2012. N2 - Melioidosis frequently presents as severe sepsis or septic shock. Appropriate managementtherefore dictates familiarity with standard sepsis therapies and approaches to intensive care. These treatments include early and aggressive haemodynamic management using intravenous fluids, vasopressors, and inotropes in a goal-directed fashion to maximise oxygen delivery to peripheral tissues. In the critically ill patient, oxygen consumption can be reduced with antipyretics, sedation, and mechanical ventilation. The role of glycaemic control and adjunctive treatments such as corticosteroids, activated protein C and granulocyte colony stimulating factor (G-CSF) are controversial. G-CSF has been formally studied in melioidosis patients, but the level of evidence for adjunctive treatments is insufficient. Mechanical ventilation for respiratory failure or acute ...
The etiologic agent of human and animal melioidosis is Burkholderia pseudomallei (5, 17). Both B. pseudomallei and its close species relative Burkholderia mallei are microbes recognized as having the potential for misuse as biological weapons (1). Typically, signs of pneumonia in patients with clinical melioidosis are a secondary result of sepsis (5). Presumably, victims suffering from a biological attack that employed B. pseudomallei or B. mallei would present clinically with pneumonic disease as the initial aspect. In order to develop a vaccine program for defending U.S. military forces against a potential B. mallei or B. pseudomallei attack, whole-body aerosol laboratory models of disease were established. With these murine melioidosis models, future vaccine candidates can be evaluated and tested for efficacy.. B. pseudomallei strain 1026b was selected because of its ease of genetic manipulation, its ability to replace genes, and its previously characterized virulence (6, 17). The 50% lethal ...
Melioidosis, caused by the highly recombinogenic bacterium Burkholderia pseudomallei, is a disease with high mortality. Tracing the origin of melioidosis outbreaks and understanding how the bacterium spreads and persists in the environment are essential to protecting public and veterinary health and reducing mortality associated with outbreaks. We used whole-genome sequencing to compare isolates from a historical quarter-century outbreak that occurred between 1966 and 1991 in the Avon Valley, Western Australia, a region far outside the known range of B. pseudomallei endemicity. All Avon Valley outbreak isolates shared the same multilocus sequence type (ST-284), which has not been identified outside this region. We found substantial genetic diversity among isolates based on a comparison of genome-wide variants, with no clear correlation between genotypes and temporal, geographical or source data. We observed little evidence of recombination in the outbreak strains, indicating that genetic ...
Melioidosis, caused by the highly recombinogenic bacterium Burkholderia pseudomallei, is a disease with high mortality. Tracing the origin of melioidosis outbreaks and understanding how the bacterium spreads and persists in the environment are essential to protecting public and veterinary health and reducing mortality associated with outbreaks. We used whole-genome sequencing to compare isolates from a historical quarter-century outbreak that occurred between 1966 and 1991 in the Avon Valley, Western Australia, a region far outside the known range of B. pseudomallei endemicity. All Avon Valley outbreak isolates shared the same multilocus sequence type (ST-284), which has not been identified outside this region. We found substantial genetic diversity among isolates based on a comparison of genome-wide variants, with no clear correlation between genotypes and temporal, geographical or source data. We observed little evidence of recombination in the outbreak strains, indicating that genetic ...
Background. Recurrent melioidosis occurs in ∼6% of patients in the first year following the initial presentation. A recent study revealed that 25% of patients with recurrence had reinfection rather than a relapse resulting from a failure to cure. The aim of this study was to reevaluate these 2 patient groups to define their individual risk factors.. Methods. All adult patients who presented to Sappasithiprasong Hospital (Ubon Ratchathani, in northeast Thailand) with culture-confirmed melioidosis during the period 1986-2004 and who survived to receive oral antimicrobial therapy were observed until July 2005. Clinical factors and antimicrobial treatment of patients with recurrent disease due to relapse or reinfection, as confirmed by bacterial genotyping, were compared using a time-varying Cox proportional hazard model.. Results. Of 889 patients who survived and underwent follow-up, 86 patients (9.7%) presented with relapse, and 30 patients (3.4%) became reinfected. There was no difference in ...
Melioidosis, a potentially fatal tropical infection, is said to be underdiagnosed in low-income countries. An increase in melioidosis cases in Sri Lanka allowed us to analyze the relationship among clinical outcome, bacteriology, epidemiology, and geography in the first 108 laboratory-confirmed cases of melioidosis from a nationwide surveillance program. The additional 76 cases of laboratory-confirmed melioidosis confirmed additional associations between Burkholderia pseudomallei multilocus sequence typing (MLST) and infection phenotype; ST1137/unifocal bacteremic infection (χ2 = 3.86, P < 0.05), ST1136/multifocal infection without bacteremia (χ2 = 15.8, P < 0.001), and ST1132/unifocal nonbacteremic infection (χ2 = 6.34, P = 0.02). ST1137 infections were predominantly seen in the Western Province, whereas ST1132, 1135, and 1136 infections predominated in the Northwestern Province. Early participating centers in the surveillance program had a lower melioidosis-associated mortality than later
TY - JOUR. T1 - Thalassemia Major Is a Major Risk Factor for Pediatric Melioidosis in Kota Kinabalu, Sabah, Malaysia. AU - Fong, SM. AU - Wong, Ke. AU - Fukushima, Masako. AU - Yeo, Tsin. PY - 2015/6/15. Y1 - 2015/6/15. N2 - Background: Melioidosis is an important cause of community-acquired infection in Southeast Asia and northern Australia. Studies from endemic countries have demonstrated differences in the epidemiology and clinical features among children diagnosed with melioidosis. This suggests that local data are needed to determine the risk factors and outcome in specific areas.Methods: This was a retrospective study of all children admitted to Likas Womens and Children Hospital, Kota Kinabalu, Sabah, Malaysia, with a blood or clinical sample positive for Burkholderia pseudomallei from 2001 to 2012.Results: Of 28 children with confirmed melioidosis, 27 records were reviewed including 11 (41%) children with thalassemia major. Twenty of the children had bacteremia, and 16 (59%) had a fatal ...
Melioidosis is caused by the Gram-negative bacillus Burkholderia pseudomallei. Most clinical reports of disease are from south-east Asia and northern Australia. The organism is intrinsically resistant to most commonly available antibiotics. Standard therapy includes ceftazidime either alone or in combination with co-trimoxazole. The clinical advantage in adding cotrimoxazole has never been determined; nor has the activity of newer, fourth-generation cephalosporins, such as cefepime, been studied in the treatment of this condition. BALB/c mice have been shown to represent an animal model of melioidosis. This animal model was used in this study to compare the efficacy of ceftazidime and cefepime alone or with co-trimoxazole, in the therapy of melioidosis. Antibiotic levels in the mice were determined by HPLC, and dosing was modified to keep plasma antibiotic levels at or above the MIC for the organism-antibiotic combination for a significant part of a 12 h period. Bacterial load, as determined by ...
This report published in Communicable Diseases Intelligence Volume 27, No 2, June 2003 describes the epidemiology of melioidosis, which is caused by the Gram negative bacterium Burkholderia pseudomallei and is endemic in northern Australia.
Melioidosis is a tropical disease caused by the bacterium Burkholderia pseudomallei. Outbreaks are uncommon and can generally be attributed to a single point source and strain. We used whole-genome sequencing to analyse B. pseudomallei isolates collected from an historical 2-year long case cluster that occurred in a remote northern Australian indigenous island community, where infections were previously linked to a contaminated communal water supply. We analysed the genome-wide relatedness of the two most common multilocus sequence types (STs) involved in the outbreak, STs 125 and 126. This analysis showed that although these STs were closely related on a whole-genome level, they demonstrated evidence of multiple recombination events that were unlikely to have occurred over the timeframe of the outbreak. Based on epidemiological and genetic data, we also identified two additional patients not previously associated with this outbreak. Our results confirm the previous hypothesis that a single ...
A definitive diagnosis is made by culturing the organism from any clinical sample, because the organism is never part of the normal human flora.. A definite history of contact with soil may not be elicited, as melioidosis can be dormant for many years before manifesting. Attention should be paid to a history of travel to endemic areas in returned travellers. Some authors recommend considering possibility of melioidosis in every febrile patient with a history of traveling to and/or staying at endemic areas.. A complete screen (blood culture, sputum culture, urine culture, throat swab, and culture of any aspirated pus) should be performed on all patients with suspected melioidosis (culture on blood agar as well as Ashdowns medium). A definitive diagnosis is made by growing B. pseudomallei from any site. A throat swab is not sensitive, but is 100% specific if positive, and compares favourably with sputum culture. The sensitivity of urine culture is increased if a centrifuged specimen is cultured, ...
Evidence is well documented that Pseudomonas pseudomallei, the cause of melioidosis in animals and man, is a soil organism that occurs mainly in tropical and sub-tropical climates (Cambon 1955: Forunier 1965; Jananetra et al 1974). This letter is to report the idolation of 9 strains of Ps. pseudomallei from the soil and 3 strains from muddy water that drained into artifically-made holes in a 5 ha sheep paddock at the Animal Health Station, Oonoonba, where natural infections occur yearly during the wet season. The morphological, cultural and biochemical characteristics of the isolates agreed with those set down by Cottew (1950) and Laws (1964).. ...
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may be the etiological agent of human melioidosis, a disease with a broad spectrum of clinical manifestations ranging from fatal septicemia to chronic localized infection or asymptomatic latent infection. interferon (IFN-), interleukin-6 (IL-6), monocyte JIB-04 chemotactic protein-1 (MCP-1), and tumor necrosis factor- (TNF-) were induced during chronic infection, and histopathological analysis showed features in common with human melioidosis. Interestingly, many of these features were similar to those induced by in humans, such as development of a collagen cord that encapsulates the lesions, the presence of multinucleated giant cells, and granulomas with a caseous necrotic center, which may explain why chronic melioidosis is often misdiagnosed as tuberculosis. Our model now provides a relevant and practical tool to define the immunological features of chronic melioidosis and aid in the development of more effective treatment of this disease in humans. is a Gram-negative soil bacterium that is ...
Health officials are stepping up public education and public hygiene campaigns advising people about boiling water, wearing boots in flood waters, etc.. For your information: Massey University researchers produce Leptospirosis video series. Melioidosis (also known as Whitmore disease and Nightcliff gardeners disease) is caused by the bacterium, Burkholderia pseudomallei. The disease though somewhat rare has been seen in areas of Southeast Asia and Northern Australia, particularly after heavy rains. In Thailand it is considered a disease of rice farmers.. The organism is saprophytically found in soil and water. People usually get infected by contact with contaminated soil or water through skin wounds, inhalation or rarely through ingestion of contaminated water.. Person to person transmission can occur through contact with blood and body fluids of an infected person.. Depending on how heavy the infection incubation can range from hours to weeks. Infection may show no symptoms but it can quickly ...
A virulent strain of Pseudomonas pseudomallei was subjected to ultraviolet irradiation and a mutant clone requiring preformed adenine or hypoxanthine for growth was isolated. The imposition of auxotrophism was associated with a striking decline in virulence for mice which could be restored by permitting the strain to revert to purine independence in vitro. The mutant persisted in mice without detected reversions or or untoward effects for approximately 20 days following inoculation of 107 cells. After repeated inoculations, a significant immune response was demonstrated by parenteral challenge with diverse strains of this species. However, animals so immunized remained susceptible to lethal respiratory infection.. ...
Yap, E.H.,Thong, T.W.,Tan, A.L.,Yeo, M.,Tan, H.C.,Loh, H.,Teo, T.P.,Thong, K.T.,Singh, M.,Chan, Y.C. (1995). Comparison of Pseudomonas pseudomallei from humans, animals, soil and water by restriction endonuclease analysis.. Singapore Medical Journal 36 (1) : 60-62. [email protected] Repository ...
A review of case records for 1817 Thai patients with melioidosis revealed that ,10% of the 382 patients with diabetes mellitus were insulin dependent. This provides evidence against the hypothesis that insulin deficiency contributes to the known susceptibility to melioidosis in patients with diabetes mellitus.. ...
Melioidosis is diagnosed by isolating Burkholderia pseudomallei from blood, urine, sputum, skin lesions, or abscesses; or by detecting an antibody response to the bacteria.
Melioidosis needs a prolonged treatment for the complete cure of the disease. B. pseudomallei is resistant to aminoglycosides, penicillin, first and second generation cephalosporins, ampicillin and polymyxin. Treatment consists of an intensive phase lasting for 10-14 days followed by an eradication phase for 3-6 months. Ceftazidime, Meropenem or Imipenem are given parenterally in intensive phase and TMP-SMX orally in eradication phase. (1,3,11) Amoxicillin-clavulanate and doxycycline can be used (12) however, are less efficacious than TMP-SMX. Amoxicillin-clavulanate is recommended in pregnant women due to the adverse pregnancy outcomes associated with TMP-SMX. (3) Ceftazidime and Meropenem was used in intensive phase treatment for two episodes, whereas Ceftazidime and Meropenem alone was used for one episode each. TMP-SMX was used in eradication phase for all the episodes. Post-exposure prophylaxis with TMP-SMX or amoxicillin-clavulanate for 21 days is recommended. (3) Blood culture should be ...
TUESDAY, July 7, 2020 (HealthDay News) -- A potentially deadly antibiotic-resistant bacteria could be hiding in the dirt and water of the southernmost U.S. states, warns a new report from the U.S. Centers for Disease Control and Prevention.. The bacterial infection, called melioidosis, caused the lungs of a 63-year-old Texan to shut down in late 2018, forcing doctors to put him on a ventilator to save his life, the researchers said.. U.S. citizens whove caught melioidosis in the past typically picked it up in a foreign country, but this man had not recently traveled abroad, said Johanna Salzer, a veterinary medical officer with the CDCs Bacterial Special Pathogens Branch.. Whats more, the bacteria that caused the mans melioidosis was genetically similar to two prior U.S. cases, one in Texas in 2004 and one in Arizona in 1999.. "We feel like this is evidence that it could be in the environment" in the United States, Salzer said. "We just need to find it.". Melioidosis is caused by the ...
Learn about the veterinary topic of Overview of Melioidosis. Find specific details on this topic and related topics from the Merck Vet Manual.
PubMed comprises more than 30 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.
The worldwide epidemiology of melioidosis is changing. We describe a case of acute melioidosis in Spain in a patient who had traveled to Africa. A novel sequence type of Burkholderia pseudomallei was identified in this patient. Clinicians should be a ...
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Looking for Whitmore's disease? Find out information about Whitmore's disease. An endemic bacterial disease, primarily of rodents but occasionally communicable to humans, caused by Pseudomonas pseudomallei and characterized by... Explanation of Whitmore's disease
According to the first-ever global burden estimates for melioidosis, the disease is sharply underreported in 45 endemic countries, its probably endemic in 34 more, and conditions are suitable for the disease in parts of the United States and Japan.. The study, published today in Nature Microbiology, has practical implications for the United States, given the 2014 outbreak linked to the Tulane Primate Research Center in Louisiana.. The findings are based on reports of human and animal cases, reports of Burkholderia pseudomallei-the bacterium that causes the disease-in the environment, and modeling that takes into account factors such as environmental suitability.. Researchers estimate that there are about 165,000 cases each year worldwide, 89,000 of them fatal, a level that calls for new policy and public health steps to battle the disease, they write.. The report includes a map of highest-risk zones, which include Southeast and South Asia, tropical Australia, west sub-Saharan Africa, and South ...
Chetchotisakd P, Chierakul W, Chaowagul W, Anunnatsiri S, Phimda K, Mootsikapun P, Chaisuksant S, Pilaikul J, Thinkhamrop B, Phiphitaporn S, Susaengrat W, Toondee Ch, Wongrattanacheewin S, Wuthiekanun V, Chantratita N, Thaipadungpanit J, Day NP, Limmathurotsakul D, Peacock S J. Trimethoprim-sulfamethoxazole versus trimethoprim-sulfamethoxazole plus doxycycline as oral eradicative treatment for melioidosis (MERTH): a multicentre, double-blind, non-inferiority, randomised controlled trial. Lancet 2014;383:807-14. [Ref.ID 97167 ...
Chetchotisakd P, Chierakul W, Chaowagul W, Anunnatsiri S, Phimda K, Mootsikapun P, Chaisuksant S, Pilaikul J, Thinkhamrop B, Phiphitaporn S, Susaengrat W, Toondee Ch, Wongrattanacheewin S, Wuthiekanun V, Chantratita N, Thaipadungpanit J, Day NP, Limmathurotsakul D, Peacock S J. Trimethoprim-sulfamethoxazole versus trimethoprim-sulfamethoxazole plus doxycycline as oral eradicative treatment for melioidosis (MERTH): a multicentre, double-blind, non-inferiority, randomised controlled trial. Lancet 2014;383:807-14. [Ref.ID 97167 ...
Neurologic melioidosis is a serious, potentially fatal form of Burkholderia pseudomallei infection. Recently, we reported that a subset of clinical isolates of B. pseudomallei from Australia have heightened virulence and potential for dissemination to the central nervous system. In this study, we demonstrate that this subset has a B. mallei-like sequence variation of the actin-based motility gene, bimA. Compared with B. pseudomallei isolates having typical bimA alleles, isolates that contain the B. mallei-like variation demonstrate increased persistence in phagocytic cells and increased virulence with rapid systemic dissemination and replication within multiple tissues, including the brain and spinal cord, in an experimental model. These findings highlight the implications of bimA variation on disease progression of B. pseudomallei infection and have considerable clinical and public health implications with respect to the degree of neurotropic threat posed to human health.
Neurologic melioidosis is a serious, potentially fatal form of Burkholderia pseudomallei infection. Recently, we reported that a subset of clinical isolates of B. pseudomallei from Australia have heightened virulence and potential for dissemination to the central nervous system. In this study, we demonstrate that this subset has a B. mallei-like sequence variation of the actin-based motility gene, bimA. Compared with B. pseudomallei isolates having typical bimA alleles, isolates that contain the B. mallei-like variation demonstrate increased persistence in phagocytic cells and increased virulence with rapid systemic dissemination and replication within multiple tissues, including the brain and spinal cord, in an experimental model. These findings highlight the implications of bimA variation on disease progression of B. pseudomallei infection and have considerable clinical and public health implications with respect to the degree of neurotropic threat posed to human health.
Melioidosis caused by the environmental gram-negative bacillus Burkholderia pseudomallei, is classically characterized by pneumonia and multiple abscesses, wit...
Cystic fibrosis (CF) is a genetic disorder characterized by progressive lung function decline. CF patients are at an increased risk of respiratory infections, including those by the environmental bacterium Burkholderia pseudomallei, the causative agent of melioidosis. Here, we compared the genomes of B. pseudomallei isolates collected between similar to 4 and 55 months apart from seven chronically infected CF patients. Overall, the B. pseudomallei strains showed evolutionary patterns similar to those of other chronic infections, including emergence of antibiotic resistance, genome reduction, and deleterious mutations in genes involved in virulence, metabolism, environmental survival, and cell wall components. We documented the first reported B. pseudomallei hypermutators, which were likely caused by defective MutS. Further, our study identified both known and novel molecular mechanisms conferring resistance to three of the five clinically important antibiotics for melioidosis treatment. Our ...
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Citation. Tumapa, S., Holden, M. T., Vesaratchavest, M., Wuthiekanun, V., Limmathurotsakul, D., Chierakul, W., Feil, E. J., Currie, B. J., Day, N. P., Nierman, W. C., Peacock, S. J.. Burkholderia pseudomallei Genome Plasticity Associated With Genomic Island Variation. BMC Genomics. 2008 Apr 25; 9(1): 190.. PubMed Citation. Abstract. ABSTRACT: BACKGROUND: Burkholderia pseudomallei is a soil-dwelling saprophyte and the cause of melioidosis. Horizontal gene transfer contributes to the genetic diversity of this pathogen and may be an important determinant of virulence potential. The genome contains genomic island (GI) regions that encode a broad array of functions. Although there is some evidence for the variable distribution of genomic islands in B. pseudomallei isolates, little is known about the extent of variation between related strains or their association with disease or environmental survival. RESULTS: Five islands from B. pseudomallei strain K96243 were chosen as representatives of ...
Background: Although melioidosis in endemic regions is usually caused by a diverse range of Burkholderia pseudomallei strains, clonal outbreaks from contaminated potable water have been described. Furthermore B. pseudomallei is classified as a CDC Group B bioterrorism agent. Ribotyping, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) have been used to identify genetically related B. pseudomallei isolates, but they are time consuming and technically challenging for many laboratories ...
Burkholderia pseudomallei is a Gram-negative bacterium that causes the serious human disease, melioidosis. There is no vaccine against melioidosis and it can be fatal if not treated with a specific antibiotic regimen, which typically includes the third-generation cephalosporin, ceftazidime (CAZ). There have been several resistance mechanisms described for B. pseudomallei, of which the best described are amino acid changes that alter substrate specificity in the highly conserved class A β-lactamase, PenA. In the current study, we sequenced penA from isolates sequentially derived from two melioidosis patients with wild-type (1.5 µg/mL) and, subsequently, resistant (16 or ≥256 µg/mL) CAZ phenotypes. We identified two single-nucleotide polymorphisms (SNPs) that directly increased CAZ hydrolysis. One SNP caused an amino acid substitution (C69Y) near the active site of PenA, whereas a second novel SNP was found within the penA promoter region. In both instances, the CAZ resistance phenotype ...
Burkholderia pseudomallei (also known as Pseudomonas pseudomallei) is a Gram-negative, bipolar, aerobic, motile rod-shaped bacterium. It is a soil-dwelling bacterium endemic in tropical and subtropical regions worldwide, particularly in Thailand and northern Australia. It infects humans and animals and causes the disease melioidosis. It is also capable of infecting plants. B. pseudomallei measures 2-5 μm in length and 0.4-0.8 μm in diameter and is capable of self-propulsion using flagella. The bacteria can grow in a number of artificial nutrient environments, especially betaine- and arginine-containing ones. In vitro, optimal proliferation temperature is reported around 40 °C in neutral or slightly acidic environments (pH 6.8-7.0). The majority of strains are capable of fermentation of sugars without gas formation (most importantly, glucose and galactose; older cultures are reported to also metabolize maltose and starch). Bacteria produce both exo- and endotoxins. The role of the toxins ...
Burkholderia pseudomallei, the etiological agent of melioidosis, is a saprophytic bacterium existing endemically in the water and soil of SE Asia and Northern Australia. This organism has shown the ability to remain dormant in its host for decades. B. thailandensis is a closely related non-pathogenic near neighbor that is also found in these soils. It has been suggested that free-living amoeba could be natural reservoirs for these organisms. The interactions of Burkholderia species and Acanthamoeba castellanii, a species of free-living amoeba, were studied to better understand the natural ecology of these organisms and to determine the effects amoeba interactions might have on pathogenesis. In this study, the adherence and persistence of several B. pseudomallei clinical isolates were compared to that of B. thailandensis within both amoeba and a human monocyte cell line. Results showed that B. pseudomallei isolates can enter amoeba and survive therein at varying levels of efficiency. Some isolates were
Burkholderia pseudomallei is the causative agent of melioidosis, a fatal human tropical disease. The non-specific DNA-binding protein DpsA plays a key role in protecting B. pseudomallei from oxidative stress mediated, for example, by organic hydroperoxides. The regulation of dpsA expression is poorly understood but one possibility is that it is regulated in a cell population density-dependent manner via N-acylhomoserine lactone (AHL)-dependent quorum sensing (QS) since a lux-box motif has been located within the dpsA promoter region. Using liquid chromatography and tandem mass spectrometry, it was first established that B. pseudomallei strain PP844 synthesizes AHLs. These were identified as N-octanoylhomoserine lactone (C8-HSL), N-(3-oxooctanoyl)homoserine lactone (3-oxo-C8-HSL), N-(3-hydroxyoctanoyl)-homoserine lactone (3-hydroxy-C8-HSL), N-decanoylhomoserine lactone (C10-HSL), N-(3-hydroxydecanoyl) homoserine lactone (3-hydroxy-C10-HSL) and N-(3-hydroxydodecanoyl)homoserine lactone (3-hydroxy-C12-HSL)
p>The checksum is a form of redundancy check that is calculated from the sequence. It is useful for tracking sequence updates.,/p> ,p>It should be noted that while, in theory, two different sequences could have the same checksum value, the likelihood that this would happen is extremely low.,/p> ,p>However UniProtKB may contain entries with identical sequences in case of multiple genes (paralogs).,/p> ,p>The checksum is computed as the sequence 64-bit Cyclic Redundancy Check value (CRC64) using the generator polynomial: x,sup>64,/sup> + x,sup>4,/sup> + x,sup>3,/sup> + x + 1. The algorithm is described in the ISO 3309 standard. ,/p> ,p class="publication">Press W.H., Flannery B.P., Teukolsky S.A. and Vetterling W.T.,br /> ,strong>Cyclic redundancy and other checksums,/strong>,br /> ,a href="http://www.nrbook.com/b/bookcpdf.php">Numerical recipes in C 2nd ed., pp896-902, Cambridge University Press (1993),/a>),/p> Checksum:i ...
p>The checksum is a form of redundancy check that is calculated from the sequence. It is useful for tracking sequence updates.,/p> ,p>It should be noted that while, in theory, two different sequences could have the same checksum value, the likelihood that this would happen is extremely low.,/p> ,p>However UniProtKB may contain entries with identical sequences in case of multiple genes (paralogs).,/p> ,p>The checksum is computed as the sequence 64-bit Cyclic Redundancy Check value (CRC64) using the generator polynomial: x,sup>64,/sup> + x,sup>4,/sup> + x,sup>3,/sup> + x + 1. The algorithm is described in the ISO 3309 standard. ,/p> ,p class="publication">Press W.H., Flannery B.P., Teukolsky S.A. and Vetterling W.T.,br /> ,strong>Cyclic redundancy and other checksums,/strong>,br /> ,a href="http://www.nrbook.com/b/bookcpdf.php">Numerical recipes in C 2nd ed., pp896-902, Cambridge University Press (1993),/a>),/p> Checksum:i ...
The work was undertaken to expand the tools available for researching Burkholderia pseudomallei (Bp), the etiological agent of the tropical disease melioidosis. Melioidosis has the potential to pose a severe threat to public health and safety. In the United States, Bp is listed as a Tier-1 select agent by the Centers for Disease Control and Prevention (CDC), thus requiring high levels of regulation and biosafety level 3 (BSL3) facilities for experimental manipulation of live organisms. An avirulent ∆purM derivative of strain 1026b (Bp82) has proven to be a valuable tool for biosafe research as a select-agent excluded strain, but the high level of genetic diversity between Bp strains necessitates an expansion of the biosafe toolset. The ∆purM mutation was recapitulated in the Bp 576a strain, a serotype B background. An important difference between strains 1026b and 576a is the lipopolysaccharide (LPS), a major virulence factor and protective antigen. Polyclonal sera from 1026b-challenged non-human
TY - JOUR. T1 - Epidemiological tracking and population assignment of the non-clonal bacterium, burkholderia pseudomallei. AU - Dale, Julia. AU - Price, Erin P.. AU - Hornstra, Heidie. AU - Busch, Joseph D.. AU - Mayo, Mark. AU - Godoy, Daniel. AU - Wuthiekanun, Vanaporn. AU - Baker, Anthony. AU - Foster, Jeffrey T. AU - Wagner, David M. AU - Tuanyok, Apichai. AU - Warner, Jeffrey. AU - Spratt, Brian G.. AU - Peacock, Sharon J.. AU - Currie, Bart J.. AU - Keim, Paul S. AU - Pearson, Talima R. PY - 2011/12. Y1 - 2011/12. N2 - Rapid assignment of bacterial pathogens into predefined populations is an important first step for epidemiological tracking. For clonal species, a single allele can theoretically define a population. For non-clonal species such as Burkholderia pseudomallei, however, shared allelic states between distantly related isolates make it more difficult to identify population defining characteristics. Two distinct B. pseudomallei populations have been previously identified using ...