Pseudomonas (dal gr. Tatuaggio infetto: come riconoscerlo e cosa fare? The respiratory tract is the most common site of infection. 18.6). They grow well on standard broth and solid media such as blood agar, chocolate agar, and MacConkey agar, which are recommended to isolate Pseudomonas species from clinical specimens. It also protects the bacterium from phagocytosis. 2001). Transmission can also occur via arthropod bites. Weak lactose fermenters will form colonies slower than the rest. Commercial selective media are available for P. aeruginosa and usually contain cetrimide, acetamide, nitrofurantoin, or 9-chloro-9(4-diethylaminophenyl)-9,10-dihydro-10-phenylacridine hydrochloride. Comprovata esperienza in tecniche analitiche per la ricerca di indicatori di igiene di processo e sicurezza (alimentare e ambientale). Pseudomonas aeruginosa is classified as a member of the fluorescent pseudomonad group which produce pyoverdin. Antimicrobial Stewardship: How the Microbiology Laboratory Can Right the Ship. Exotoxin A (ADP-ribosyl-transferase) Cool the medium to approximately 50C and pour into sterile Petri dishes. Primary lesions occur at the point of entry (skin or mucosal surfaces) with dissemination via the lymphatic system and dissemination by the bloodstream. Isolation Basic shape of colonies: circular Elevation (cross sectional shape of the colony): raised Margin: undulate Pigmet production: pyocyanin (blue-green) Compare P.aeruginosa with S.aureus (yellow colony in detail) Basic shape of colony: circular This microorganism has also been isolated from the semen of boars and bulls, diminishing semen quality and viability and resulting in impaired fertilization and embryonic development in vitro (Bielanski etal. While the bacterium is a pathogen that is responsible for various hospital-acquired infections, these infections are particularly severe among individuals with a compromised immune system. Transmission occurs from infected animals via contaminated food and water and less commonly from aerosols and infection of wounds. Pseudomonas aeruginosa is a member of the genus Pseudomonas. Related Pyoverdin, once called fluorescin, will fluoresce under ultra-violet light. A biohazard cabinet must be used and all other safety procedures employed according to biosafety level (BSL)-3 guidelines. LPS is involved in adherence and invasion and its lipid A part mediates inflammation and tissue damage. Virulence factors such as capsular material, LuxI and LuxR quorum-sensing signals, a possible antigenic variation system and a type III secretion system have been reported for B. mallei. The green-blue pyocyanin pigment is most obvious in areas of heaviest growth.< div class='tao-gold-member'> Phospholipase C (haemolysin) SUMMARY: A study of phytopathogenic pseudomonads was begun, but it was found that they could not easily be differentiated from the commonly occurring soil- and water-inhabiting fluorescent pseudomonads. I batteri che fermentano il lattosio si presentano sotto forma di colonie con varie sfumature di rosso poich producono acidi misti che fanno scendere il pH. species. These will be varied and will depend on the clinical signs and lesions. Many Gram-negative pathogens regulate virulence factor expression by using a cell density mechanism termed quorum sensing. Preparation of MacConkey agar. In questo terreno, infatti, sono presenti sia il cristalvioletto che i sali biliari i quali sono in grado di inibire la crescita dei batteri Gram positivi (ed anche quella dei Gram negativi pi esigenti dal punto di vista nutrizionale). This organism is unable to survive in the environment for more than two weeks. In addition to animal exposure, cases of human-to-human transmission have been reported. It is used in the differentiation of lactose fermenting from lactose non-fermenting gram-negative bacteria. Pseudomonas aeruginosa is found infrequently as part of the microbial flora of healthy animals. A single prokaryotic, flagellated "P. putida F1" organism. The typical lesions are nodules which may suppurate and can form in any tissue, including the brain. Thank you sir for your excellent notes, it really guides me in the treatment plant where im working as a microbiologist in the lab. Thank you so much. Other virulence factors of note include the ability to form a biofilm, adherence and the ability to invade respiratory epithelial cells (Di Bonaventura etal. Malleobactin is a siderophore involved in iron acquisition (Alice etal. [1] are motile due to one (e.g. Pili are the major adhesins implicated in the initial attachment phase to host tissues. MacConkey agar with bile salt- Selective for gram-negative bacteria but . This is a limitation of this particular growth medium. After overnight incubation at 37C, check the growth of the organisms and colony morphology. Di y l lng cha vitamine trong mt vi loi vi sinh vt (/g trng lng kh) Enterobacter Pseudomonas Clostridium Torulopin Vitamine acrogenes fluorescens butyricum utilis Acid 249 210 250 500 nicotinic Riboflavin 44 67 55 49 Thiamine 11 26 9 6.2 Piridoxin 7 6 6 - Acid 140 91 93 130 pantotenic Acid folic 14 9 3 2.8 Biotin 4 7 - 1.8 +Enzyme: Nh nhng sinh . This bacterium is frequently found in aerators and traps of sinks. 2003, Althouse & Lu 2005). Treasure Island (FL): StatPearls Publishing; 2022 Jan-. 2000). Many health care professionals are involved in this process, and proper communication and coordination will enhance patient-centered care, improve outcomes, patient safety, and enhance team performance. Download Genome Learn about our Enhanced Authentication Initiative. 2003) including P. fluorescens (septicaemia in rainbow trout and Tilapia and necrotizing hepatitis in pet birds), P. putida (endotoxic shock in a cynomolgous macaque) and B. cepacia, formerly P. cepacia (outbreak of subclinical mastitis in a flock of dairy sheep). Pseudomonas fluorescens is represented by seven biotypes denoted by the letters A, B, C, D, E, F, and G (Stanier et al. Inoculate and streak the specimen as soon as possible after collection. Neutral red is a pH indicator that turns from off-white to bright red/pink as the pH drops below 6.8. Burkholderia mallei once had a wide geographical distribution but now is mainly seen in China and Mongolia with pockets of infection in India, Iraq, Turkey and the Philippines. Another feature associated with Pseudomonas is the secretion of pyoverdin (fluorescein, a siderophore . P. fluorescens conosciuto principalmente per aver creato problemi nellindustria alimentare, presenta diversi fattori di virulenza che rendono i ceppi anche patogeni per luomo. Zoonotic transmission has not been documented. P. fluorescens, P. putida, P. luteola). Commercial selective media are available for P. aeruginosa and usually contain cetrimide, acetamide, nitrofurantoin, or 9-chloro-9(4-diethylaminophenyl)-9,10-dihydro-10-phenylacridine hydrochloride. These bacteria are strict aerobes, non-spore-forming, oxidative, catalase-positive, oxidase-positive (except P. oryzihabitans, P. luteola and the genus Stenotrophomonas) and most are motile by one or several polar flagella (except B. mallei). 1996 ). 18.6). 2001) and one of the factors facilitating its persistence in the body. mycoplasma PPLO, Your example of vulgaris and aureus look like they have been switched to me. Strains of P. aeruginosa produce the water-soluble diffusible pigments pyocyanin (blue, phenazine pigment), pyoverdin (water-soluble yellow-green or yellow-brown pigment), pyorubin (red) and pyomelanin (dark brown) (Fig. Practical Guidance for Clinical Microbiology Laboratories: Diagnosis of Bacterial Gastroenteritis. 2004). However, direct microscopy of Gram-stained smears with B. pseudomallei will often reveal small Gram-negative bacilli with bipolar staining, safety pin appearance. The growth of B. mallei is enhanced by 1% glycerol. P. aeruginosa, P. stutzeri, P. oryzihabitans; Figure 181-1) or more polar flagella (e.g. 1994). Stenotrophomonas species tend to be straight and slightly smaller (0.40.7m 0.71.8m). Human infection has occurred rarely and sporadically among laboratory workers and also those in direct contact with infected, domestic animals. fluorescence. Two species of the genus Burkholderia (formerly rRNA group II pseudomonads), B. mallei and B. pseudomallei, are generally recognized as important animal or human pathogens. Pseudomonas and Stenotrophomonas can be handled in a biosafety level-2 laboratory. Stenotrophomonas maltophilia is also considered an opportunistic pathogen which can cause a variety of infections in veterinary medicine. Pseudomonas and Stenotrophomonas can be handled in a biosafety level-2 laboratory. A biohazard cabinet must be used and all other safety procedures employed according to biosafety level (BSL)-3 guidelines. 2004). Identification Lactose fermentation will produce acidic byproducts that lower the pH, and this turns the pH indicator to pink. Pseudomonas aeruginosa will also grow on many of the selective media intended for the Enterobacteriaceae such as MacConkey, brilliant green and XLD agars. MacConkey Agar Is Selective for Non-fastidious Gram-negative Organisms Therefore, MacConkey needed a way to limit this background of environmental flora and allow only his organisms of interest to grow. Pseudomonas fluorescens, present in soil and water, is associated with food spoilage and lesions in reptiles and fish (Sakai etal. Pseudomonas. As a result, they can be problematic in hospital settings. Pyocyanin, a bluish pigment unique to P. aeruginosa, gives the blue-green colour associated with many cultures. Direct microscopy University of Horticultural Sciences, Bagalkot, Karnataka, India. It is nonsporeforming and is motile by one or more flagella. A simple procedure for the preliminary identification of aerobic gram negative intestinal bacteria with special reference to the Enterobacteriaceae. Pls continue your service to Microbiology, Dr. Manjunath Ramanna MacConkey agar (MAC) is a bacterial culture medium named after bacteriologist Alfred T. MacConkey (1861-1931). Neutral red is a pH indicator that turns red at a pH below 6.8 and is colorless at any pH greater than 6.8. Pyoverdin, once called fluorescin, will fluoresce under ultra-violet light. It may be that Enterococcus and Staphylococcus ferment lactose, but wouldnt the crystal violet and bile salts inhibit their growth? Sterilize by autoclaving at 121C for 15 minutes. 2022 Microbiologia Italia - Il primo sito di divulgazione scientifica microbiologica, Fai clic per condividere su Facebook (Si apre in una nuova finestra), Fai clic per condividere su WhatsApp (Si apre in una nuova finestra), Fai clic qui per condividere su Twitter (Si apre in una nuova finestra), Fai clic qui per condividere su LinkedIn (Si apre in una nuova finestra), Fai clic per condividere su Telegram (Si apre in una nuova finestra), Cara Flora mia: Batteri buoni e cattivi della flora batterica, CRISPR-Cas9: taglia ed incolla interi genomi batterici, Giornata mondiale contro il Papilloma Virus. Some strains produce all four pigments. A selective medium for B. mallei can be made by adding 1000 units polymyxin E, 1250 units bacitracin and 0.25mg actidione to 100mL of trypticase soy agar. Stenotrophomonas maltophilia is also considered an opportunistic pathogen which can cause a variety of infections in veterinary medicine. Gould's S1 agar plates were made not later than the day before in order to preserve the level of antibiotics (storage in a refrigerator produces a problematic coating on the plates). Pseudomonas fluorescens strain NCTC 10038 is a whole-genome sequenced bacterial type strain. Main virulence factors of Pseudomonas aeruginosa Allow the plates to warm at 37C or to room temperature, and the agar surface to dry before inoculating. Potential sources of P. aeruginosa are diverse including disinfectants, ointments, soaps, eye drops, irrigation fluids and equipment. Key components of the MacConkey medium include crystal violet dye, bile salts, lactose, and neutral red (pH indicator). In continuo aggiornamento in campo microbiologico. Suspend 45.3g of Pseudomonas Cetrimide Agar in 1 litre of distilled water. Macconkey agar is Known to he the selective media for culturing Gram negative bacteria and some of Gram positive bacteria;so for that case staphylococcus gives pale pink color in M.A because it is able to grow in this medium. 1.07267. Jung B, Hoilat GJ. [10] Pseudomonas putida is a aerobic, gram negative, rod shaped bacteria. Pseudomonas, Stenotrophomonas and Burkholderia species have a worldwide distribution. Cytotoxic, invasion of tissue and cellular damage, immunosuppressive action Isolated from soil, plants, water surfaces, rarely from clinical samples. The type III secretion system consists of bacterial proteins which act as a syringe to deliver cytotoxins into the cytoplasm of host cells. 2007). http://tesi.cab.unipd.it/44793/1/Don%C3%A0_Alberto.pdf. Main diseases caused by the major pathogenic Pseudomonas, Burkholderia and Stenotrophomonas species in veterinary medicine. The diagnostic potential is immense. Functions I share & use your blogs for teaching my Uunder graduate students. Pseudomonas aeruginosa and S. maltophilia are both considered opportunistic pathogens and can cause a variety of infections (Table 18.1). The culture was isolated from pre-filter tanks and has applications in bioinformatics, water testing, and antimicrobial preservative testing. This gives sticky, wet-appearing colonies. Ps. Under particular conditions, P. aeruginosa can produce an alginate structure which is a slime-like, mucoid exopolysaccharide. 18.3). Tags: Clinical Veterinary Microbiology
In addition to Pseudomonas, two of these genera are of significance in veterinary medicine: Burkholderia and Stenotrophomonas. MacConkey agar is used for the selective isolation and identification of members of the family Enterobacteriaceae from feces, urine, wastewater, and foods. Stenotrophomonas maltophilia is resistant to many antimicrobials (Denton & Kerr 1998) and mainly causes hospital-acquired infections in humans. Final pH 7.2 0.2 @ 25C. This pathogen is a facultative intracellular bacterium which has a wide host range, including humans, horses, sheep, goats, dogs, cats, cattle, and pigs. Just curious. 3) per essere sottoposte alle prove biochimiche quali il test dellossidasi, il test di fermentazione/ossidazione degli zuccheri. As P. aeruginosa is resistant to many antimicrobials, it frequently causes infection in animals undergoing antibiotic treatment or in immunocompromised hosts. putida (6). It has emerged as an opportunistic pathogen in animals and immunocompromised humans. 2001). Few microorganisms are necessary to cause this contagious disease. The growth of B. mallei is enhanced by 1% glycerol. The manifestations of the disease depend on the extent and distribution of the lesions in the animal. A number of saprophytic Pseudomonas species and Burkholderia species have been implicated in occasional infections of animals (Jackson & Phillips 1996, Berriatua etal. Based on the ability to ferment lactose, different species will yield colonies in varying appearance on a MacConkey medium. 2001, Matchett etal. In: StatPearls [Internet]. fluorescens deriva dalla capacit di tale microrganismo di rilasciare, in ambienti con carenza di ferro, un pigmento solubile fluorescente chiamato Pioverdina che agisce da sideroforo. Most strains give a clear zone of haemolysis on blood agar (Fig. MacConkey agar is a bacterial culture medium that is generally used for species found in the gut. Possiede flagelli ed positivo alla prova dellossidasi. When pyoverdin is combined with pyocyanin, the bright green colour characteristic of P. aeruginosa is expressed. Other virulence factors of note include the ability to form a biofilm, adherence and the ability to invade respiratory epithelial cells (Di Bonaventura etal. They have a predilection for aqueous environments, surviving well in them. It was stored in the refrigerator. Therefore, lactose-fermenting-gram-negatives (lactose-fermenters) will form pink colonies, while non-lactose fermenters will form off-white opaque colonies. Pseudomonas fluorescens is an unusual cause of disease in humans, and usually affects patients with compromised immune systems (e.g., patients on cancer treatment). Burkholderia pseudomallei is the aetiological agent of melioidosis, a disease in which treatment failures and relapses are common, with pneumonia as the most common clinical presentation. Media such as Pseudomonas agar P (BD Diagnostics) (Fig. Many Gram-negative pathogens regulate virulence factor expression by using a cell density mechanism termed quorum sensing. Inoculate stool in selenite F broth or tetrathionate broth and incubate. These virulence factors all play a role in disease pathogenesis (Table 18.2). However, this classification has undergone revision and Pseudomonas species have now been reclassified into many different genera. in some lab Macconkey Broth Neutral Red and Dilution water in which 2 pillows used(1 pillow of Magnesium Chloride and 1 pillow of Potassium Dihydrogen Phosphate Pillow) used why they use these 2 pillows? Crystal violet dye and bile salts halt the growth of gram-positive bacteria. The toxins are involved in epithelial cell damage and in the inhibition of phagocytic cells. The process of fermentation produces acid which is detected by a phenol red indicator. Batterio gram-negativo e aerobio obbligato, Pseudomonas fluorescens (fig.1) presenta un metabolismo molto versatile, lo possiamo trovare nel suolo e nelle acque superficiali. [Updated 2022 Sep 26]. Burkholderia mallei once had a wide geographical distribution but now is mainly seen in China and Mongolia with pockets of infection in India, Iraq, Turkey and the Philippines. Preparation of MacConkey Agar Weigh and suspend 50 grams of MacConkey agar powder in 1 Litre of purified water and mix thoroughly. Damage to host cell membranes and impaired mucociliary clearance 2007). how come staph is pale pink while it doset grow on macc at all ? 18.5) will enhance pyocyanin production and Pseudomonas agar F (BD Diagnostics) enhances pyoverdin production (Fig. LPS is involved in adherence and invasion and its lipid A part mediates inflammation and tissue damage. Interestingly, pyocyanin can colour pus and stain wool a greenish blue. Pseudomonas aeruginosa is rarely involved in primary disease. Per l'isolamento di P.fluorescens da campioni alimentari contaminati si utilizza il terreno selettivo Pseudomonas Agar Base (PAB) addizionato con cetramide, fucidina e cefaloridina (CFC supplement). Un articolo molto interessante; mi ha incuriosito una cosa: come mai si aggiunge del CFC al terreno di base? [1] The selective and differentiating properties of MacConkey agar enables utilization for both research and clinical applications. They are common course of food contamination. Figure 18.1 Pseudomonas aeruginosa on sheep blood agar showing large, flat, irregular-edged colonies resembling those of some Bacillus species. Pili are the major adhesins implicated in the initial attachment phase to host tissues. Main virulence factors of Pseudomonas aeruginosa. The respiratory tract is the most common site of infection. Genomic analysis of B. mallei has identified a number of putative virulence factors. It also produces several other potential virulent factors such as extracellular proteases, serine metalloprotease, haemolysin, lipase, lecithinase, endotoxin, lethal toxins, and surface capsule-like structures. Clinical microbiologists must be trained with a thorough understanding of the principles to run the tests, interpret the results, and report the findings. Add 5ml of glycerol. Its name come from the production of the soluble fluorescent pigment pyoverdin. Damage to host tissues, cytotoxic, implicated in invasion process Tatuaggio infetto: come riconoscerlo e cosa fare? Infections occur via contaminated food or water, from aerosols and contact with contaminated ground via skin abrasions or wounds. The disease usually occurs in tropical regions between 20 northern and southern latitudes but melioidosis has been reported in localized areas of France, Iran, China and the USA. The degree of. ozaenae, Staphylococcus pettenkoferi, Pasteurella pneumotropica, Achromobacter species, Pasteurella aerogenes, Moraxella species and Pseudomonas species. Il MacConkey contiene inoltre come unica fonte energetica illattosio: ci permette quindi la distinzione tra batteri fermentanti il lattosio e batteri che non fermentano questo zucchero. Stenotrophomonas species tend to be straight and slightly smaller (0.40.7m 0.71.8m). Figura 2 La filogenesi di Pseudomonas fluorescens. It also produces several other potential virulent factors such as extracellular proteases, serine metalloprotease, haemolysin, lipase, lecithinase, endotoxin, lethal toxins, and surface capsule-like structures. Bring to the boil to dissolve completely, sterilise by autoclaving at 121C for 15 minutes. Pseudomonas aeruginosa possesses cell-associated virulence factors such as pili, flagella, lipopolysaccharide and alginate/biofilm. This organism grew well on the TSA agar, LB broth and LB agar but was otherwise slow to grow in other mediums used in lab. These may also be atypical in certain biochemical reactions, making them difficult to identify. This book is distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) The genus Pseudomonas (sensu stricto) represents the rRNA homology group 1 with the type species Pseudomonas aeruginosa which is the most important veterinary pathogen in the genus Pseudomonas followed by P. fluorescens. Certolizumab Pegol e il suo ruolo contro il TNFa, Obesit in et pediatrica: una patologia da non sottovalutare, 28 febbraio 1953: 70 anni fa la scoperta del DNA. P. koreensis was first isolated from Korean agricultural soils. Gram-negative bacterial species will still form colonies, but colonies will have a white appearance as there will be no change in pH in the absence of lactose fermentation. Pyorubin and pyomelanin are less commonly produced, develop slowly and are seen best by growing the strains on nutrient agar slants at room temperature for up to two weeks. 2003) including P. fluorescens (septicaemia in rainbow trout and Tilapia and necrotizing hepatitis in pet birds), P. putida (endotoxic shock in a cynomolgous macaque) and B. cepacia, formerly P. cepacia (outbreak of subclinical mastitis in a flock of dairy sheep). Infections occur via contaminated food or water, from aerosols and contact with contaminated ground via skin abrasions or wounds. Heat to boiling to dissolve the mediumcompletely. validated cycle. This gives McConkey agar its differentiating property. Why pasturella multocida is gram negative bt does not grow on macckonkey agar. The genus Pseudomonas was originally organized into five major species clusters (rRNA homology groups).
Lactose non-fermenting strains, such as Shigella and Salmonella are colorless and transparent and typically donot alter appearance of the medium. MacConkey Medium. No. They have a predilection for aqueous environments, surviving well in them. Colonial morphology Base tested with Pseudomonas CN selektiv supplement art. The incubation period is frequently prolonged and disease signs may appear months or even years after infection. A simple screening technique for the detection of Pseudomonas aeruginosa colonies by their fluorescence on MacConkey agar under ultraviolet light is proposed. Lactose fermenting species will grow pink colonies. Other non-flourescent soluble and insoluble, pigments exist. Pili However, cases of human-to-human transmission have been reported. Burkholderia mallei, the aetiologic agent of glanders, is a listed disease by the Office International des pizooties (OIE), also known as the World Organization for Animal Health. Pseudomonas and Burkholderia species are medium-sized (0.51m 1.55m) straight or slightly curved Gram-negative rods. The cultures for P. aeruginosa, B. pseudomallei and B. mallei are incubated aerobically at 3537C for 2448 hours. These shapes include spherical, rod . Consequently, DNA/RNA hybridization confirmed the presence of five diverse rRNA groups (rRNA groups I-V) (Palleroni et al. P. aeruginosa occurs in both rough and smooth lipopolysaccharide (LPS) forms (Sadovskaya etal. Pseudomonas and Burkholderia species are medium-sized (0.51m 1.55m) straight or slightly curved Gram-negative rods. Siderophores (pyoverdin, pyocyanin, pyochelin) qual la metodica analitica di riferimento? As pyocyanin is unique to P. aeruginosa this is an important diagnostic characteristic although strains vary in the amount of the pigment they produce. Standard collection and transport methods are sufficient to ensure the recovery of Pseudomonas, Burkholderia and Stenotrophomonas species. 2006). Some strains of P. aeruginosa do not produce pigments and are highly mucoid. It also produces a number of extracellular products such as protein exotoxin A, proteases, type III secretion system exoenzymes, rhamnolipid, phospholipase C, and siderophores (pyochelin, pyocyanin, and pyoverdin). P. aeruginosa occurs in both rough and smooth lipopolysaccharide (LPS) forms (Sadovskaya etal. Pseudomonas gives negative Voges Proskauer, indole and methyl red tests, but a positive catalase test. Shouldnt they show no growth? Media such as Pseudomonas agar P (BD Diagnostics) (Fig. Log In or Register a > to continue The genome contains numerous insertion sequence elements and a vast number of simple sequence repeats. A selective medium for B. mallei can be made by adding 1000 units polymyxin E, 1250 units bacitracin and 0.25mg actidione to 100mL of trypticase soy agar. MacConkey agar without bile salt- It uses both gram-negative and gram-positive bacteria. Stenotrophomonas maltophilia is readily isolated from water, soil and sewage. Burkholderia mallei and B. pseudomallei are among the most dangerous bacteria to work with in a laboratory. The incubation period is frequently prolonged and disease signs may appear months or even years after infection. These will be varied and will depend on the clinical signs and lesions. Natural Habitat The toxins include a lethal factor with anticoagulant activity and a skin-necrotizing proteolytic agent. Il genere Pseudomonas, con numerosissime specie spesso poco correlate fra loro, stato suddiviso in cinque gruppi in base alle omologie dell'RNA ribosomiale; essi rappresenterebbero raggruppamenti genetici . Pseudomonas fluorescens Heavy growth may produce a greenish-gold fluorescent pigment. Pseudomonas aeruginosa on tryptic soy agar. and . A recovery rate of 50 % is equivalent to a productivity value of 0.5. 1989; Swain etal. Both of these species have been identified as potential agents of bioterrorism (category B biothreat agents). Any healthcare professionals handling these patient samples must be adequately trainedin orderto avoid contamination of the samples or accidental exposure and spread of potential pathogens.[6][7]. Based on the physiological characteristic, the bacteria had optimal temperature for growth with the range of 25-35C, optimal pH 7-8, and able to solubilize phosphate, nitrification,. Burkholderia mallei produces several acyl-homoserine lactones (acyl-HSLs) which serve as quorum-sensing signals (Ulrich etal.