Aims: Biocontrol of fungal plant pathogens using beneficial microorganisms is a safer alternative over synthetic fungicides. PHP12 is a bacterial strain isolated from healthy oil palm rhizosphere and is closely related to the recently described Burkholderia stagnalis, a member of the Burkholderia cepacia complex. This study aimed to characterize the antifungal activity spectrum of PHP12 and identify the antifungal compounds produced by the strain. Methodology and results: The antifungal activity of PHP12 was characterized by growing fungal strains in the presence and absence of PHP12 and measuring the radius of the antifungal zone. PHP12 inhibited the growth of fungal pathogens including Ganoderma boninense, Curvularia oryzae, Phellinus noxius and Colletotrichum capsici. However, PHP12 did not inhibit the growth of Trichoderma asperellum, a known fungal biocontrol agent. The antifungal compounds of PHP12 were precipitated using ammonium sulfate and further purified with HPLC followed by identification using Liquid Chromatography Electrospray Ionization Tandem Mass Spectrometric (LC/ESI-MS). The LC/ESI-MS analysis showed the presence of an oligopeptide with a molecular weight of 1210.63 Da. The peptide consists of heavily modified amino acids that are linked by a hexose residue. Conclusion, significance and impact of study Although characteristics of the antifungal compounds are similar to other antifungal peptides from Burkholderia such as occidiofungin, there have been no reports of antifungal peptides from B. stagnalis with the corresponding molecular weight or fragmentation profile. The novelty of the compound, as well as its antifungal spectrum, makes PHP12 an interesting strain to be investigated further as a biocontrol agent.
Fungicides, Industrial ; Burkholderia cepacia complex--pathogenicity

Aims: Burkholderia pseudomallei, the human pathogen that causes melioidosis, is intrinsically resistant towards a wide range of antibiotics and there have been reports of acquired resistance towards antibiotics used for melioidosis treatments. Antimicrobial peptides (AMP) such as bacteriocins are gaining the interests of researchers as alternative for treating infections caused by multidrug resistant bacteria. In this study, we aimed to identify Burkholderia spp. isolated from soil in Sarawak that possess the potential in inhibiting the growth of B. pseudomallei and to further characterize the antagonistic compound produced. Methodology and results: A total of 50 Burkholderia spp. isolates of environmental origin and two isolates of Ralstonia solanacearum were screened against five clinical isolates of B. pseudomallei using spot-on-lawn assay and flip streak method. Burkholderia stagnalis isolate K23/3 showed clear zones of inhibition (ZOI) in both preliminary tests. Cell-free supernatant (CFS) was obtained from B. stagnalis K23/3 broth culture and was tested via agar well diffusion assay (AWDA). The antagonistic compound secreted at the early log phase of the bacterial growth was shown to be stable in a wide range of temperatures and pH. Treatment with different enzymes revealed that it was sensitive towards proteinase K, suggesting that it is proteinaceous. The bacteriocin-like-substance (BLIS) was subjected to ammonium sulfate precipitation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The SDS-PAGE gel was overlaid with indicator B. pseudomallei isolates where the active protein was shown to be less than 7.1 kDa. Conclusion, significance and impact of study Burkholderia stagnalis isolate K23/3 was able to secrete bacteriocin-like-substance (BLIS) that has the potential in biocontrol of B. pseudomallei in the environment or as potential treatment for melioidosis.
Bacteriocins ; Burkholderia ; Burkholderia pseudomallei

Introduction: Melioidosis among Filipinos may be underreported. The causative agent, Burkholderia pseudomallei, thrives in soil and water in tropical regions. Because our country thrives on agriculture as a source of livelihood, occupational exposure through farming needs to be recognized. Case Presentation: We report a case of a 40-year-old male complaining of intermittent fever, progressive weight loss and jaundice for three weeks prompting consult. Whole abdominal ultrasound showed presence of a hepatic mass. Further evaluation using CT scan of the whole abdomen with contrast revealed multiple cystic hepatic nodules with wall/septal enhancement. He was admitted and was initially managed as sepsis secondary to a complicated intra-abdominal infection (liver abscess, pyogenic or amebic). Ciprofloxacin and metronidazole were started. Aspiration of the hepatic abscess showed many pus cells. Culture of the aspirate grew Burkholderia pseudomallei, sensitive to ceftazidime. Antibiotics were shifted accordingly. Defervescence ensued. Patient was discharged improved after two weeks of ceftazidime wo grams every eight hours given intravenously followed by a three-month oral course of cotrimoxazole 160mg/800mg tablet, two tablets every 12 hours and doxycycline 150mg capsule every 12 hours. On follow-up after three months, he had no recurrence of symptoms and was able to resume his usual work. Discussion: Melioidosis is a disease of humans and animals that is geographically restricted to tropical countries since the organism thrives in soil and water. Symptom onset may be delayed due to the ability of the organism to produce latent infection. Isolation of B. pseudomallei from clinical specimens sent for culture and sensitivity testing is the diagnostic gold standard. Conclusion Melioidosis may present as an intraabdominal infection. A high clinical index of suspicion among those with occupational exposure to contaminated soil and water is important to promptly recognize and treat this infection.
Burkholderia pseudomallei

No abstract available.
Burkholderia cepacia* ; Burkholderia*

Minimal growth inhibitory concentrations (MICs) of chitosan acetate (M.W. 60 kDa) on heterotrophic bacteria (strains MK1, S, and R) isolated from the soft-rotten tissues of Neungee mushroom (Sarcodon aspratus) were measured. The slimy substance produced by the MK1 strain was responsible for the diseased mushroom's appearance. The S and R strains were members of the Burkholderia cepacia complex. These strains showed different levels of susceptibility toward chitosan acetate. The MIC of chitosan acetate against the MK1 and S strains was 0.06%. The MIC against the R strain was greater than 0.10%. Survival fractions of the MK1 and S strains at the MIC were 3 x 10(-4) and 1.4 x 10(-3) after 24 h, and 2 x 10(-4) and 7 x 10(-4) after 48 h, respectively. Survival fractions of the R strain after 24 and 48 hr at 0.1% chitosan acetate were 1 x 10-2 and 6.9 x 10(-3), respectively. Compared to the MK1 and S strains, the low susceptibility of the R stain towards chitosan acetate could be due to the ability of the R strain to utilize chitosan as a carbon source. Thirty-eight percent of Neungee pieces treated in a 0.06% chitosan acetate solution for 2~3 second did not show any bacterial growth at 4 days, whereas bacterial growth around untreated mushroom pieces occurred within 2 days. These data suggest that chitosan acetate is highly effective in controlling growth of indigenous microorganisms on Neungee. The scanning electron micrographs of the MK1 strain treated with chitosan revealed a higher degree of disintegrated and distorted cellular structures.
Agaricales ; Bacteria ; Burkholderia cepacia complex ; Carbon ; Cellular Structures ; Chitosan ; Electrons ; Sprains and Strains

Background: Melioidosis is a potentially fatal disease caused by Burkholderia pseudomallei. Over a century after its discovery, there seems to be a paucity of reported cases in the Philippines relative to other countries where it is found to be endemic. This suggests that the true burden of melioidosis in the country is not well-defined. The rarity of the disease, its protean clinical manifestations, and the lack of pathognomonic features pose a great diagnostic challenge. Furthermore, the proper recognition of the organism is an extreme necessity as it is intrinsically resistant to numerous antibiotics and requires specific long-term treatment. Case: This is a case of a 49-year-old Filipino diagnosed with a metastatic spinal disease from a primary thyroid carcinoma and underwent posterior spinal decompression and stabilization. Revision of instrumentation was done following identification of an implant loosening. During the interim, wound dehiscence and infection developed. The patient was readmitted and underwent debridement of the lumbosacral spine. Wound cultures all yielded growth of Burkholderia pseudomallei. The patient received meropenem and then trimethoprim-sulfamethoxazole with ciprofloxacin during the intensive and eradication phase, respectively. Erythrocyte sedimentation rate and C-reactive protein were monitored and a significant reduction in both values reflected a good therapeutic response. Conclusion This is a rare case of a deep surgical site infection caused by Burkholderia pseudomallei. It is known that melioidosis is a potentially fatal infection but is under-reported in the Philippines. At present, further epidemiological studies along with an increased level of awareness of melioidosis are greatly needed to help define the true burden of illness and optimize patient management following prompt recognition.
Melioidosis ; Philippines ; Burkholderia pseudomallei

No abstract available.
Burkholderia cepacia* ; Skin*

Aims: Potassium is an essential macronutrient for the growth and development of plants. Most of potassium in the soil presented in mineral forms or non-exchangeable forms which are not available for plants. The microbial activity facilitated to release of mineral forms or non-exchangeable potassium to the exchangeable or water-soluble. This study was aimed to isolate, select, and characterize of the selected potassium solubilizing bacteria from limestone mining area in Palimanan, Cirebon Quarry. Methodology and results: Isolation and selection of bacteria was done based on potassium dissolving index in Aleksandrov media containing feldspar, non-exchangeable potassium. Thirty seven isolates of potassium solubilizing bacteria were obtained in this study. Three isolates showed higher dissolution index, namely KQC.4B.1, KQC.5A.4, and KQC.5C.5. All of isolates were Gram negative bacteria, short-rod formed, and able to dissolve potassium concentration on 10th and 20th days. The three isolates showed 99.9% physiologically similar with Burkholderia cepacia. Futhermore by using 16S rRNA gene identification, isolate KQC.5C.5 closely related with B. cepacia with 99% identity. The application of isolate KQC.5C.5 on soil showed that the isolate was able to release the solution K formed after 10th day incubation. Conclusion, significance and impact of study: Potassium solubilizing bacteria (B. cepacia) could use as a biological fertilizer for providing potassium which is available to plants grown on reclamation area of limestone quarry.
Potassium ; Burkholderia cepacia

OBJECTIVETo develop an up-converting phosphor technology-based lateral-flow (UPT-LF) assay for rapid quantitative detection of Burkholderia pseudomallei on site.

METHODSThe strip Bps-UPT-LF strip was prepared with up-converting phosphor (UCP) particles as the bio-label using double-antibody sandwich method. Detection performance, including sensitivity, quantitative accuracy, precision, and specificity, were first evaluated using bacterial suspensions of Burkholderia pseudomallei, the related species and the strains which had similar routes of transmission with serial standard concentrations diluted by phosphate buffer, then biological and chemical reagents and simulated samples with series concentrations were employed for sample tolerance evaluation, while the operation error during on site detection was also evaluated through adjusting liquid measure.

RESULTSThe whole detection was accomplished within 20 minutes, and the sensitivity was 10(4) CFU/ml with linear quantitative range from 10(4) CFU/ml to 10(7) CFU/ml, which covered four orders of magnitude. Bps-UPT-LF strip demonstrated high specificity with the absence of any false-positive result even at 10(7) and 10(8) CFU/ml of non-specific bacterial contamination. Not only Bps-UPT-LF strip could tolerate to high concentration of the extreme acid and basic matter (pH 1-12), saline matter (≤ 2 mol/L mixture of NaCl and KCl), viscous materials (≤ 50 g/L of PEG 20000 and ≤ 20% of glycerol) and bio-macromolecule (≥ 400 g/L of bovine serum albumin or ≥ 80 g/L of casein), but also it can directly detect animal, environmental and powder specimen, such as ≥ 400 g/L of milk powder, flour powder, fruit juice, fresh and decomposed viscera, and ≤ 200 g/L of putty powder, sucrose, gourmet powder, and soil. Operation errors of liquid measure had few effects on sensitivity and specificity, including -50%-200% of sample, -22%-44% of sample-treating buffer and -30%-30% of loading mixture.

CONCLUSIONThe good detection performance and tolerance performance bring the bright future for Bps-UPT-LF strip to detect Burkholderia pseudomallei on site rapidly and quantitatively for nature foci surveillance and anti-bioterrorism.

Adolescent ; Burkholderia pseudomallei ; pathogenicity ; Humans ; Male ; Pericarditis ; diagnosis ; microbiology