The bacterium Burkholderia pseudomallei is a gram-negative saprophytic bacillus that is found predominantly in Southeast Asia and tropical Australia and is the causative agent of the emerging infection melioidosis. Infection of humans with B. pseudomallei may occur by various routes, including via wounds and existing skin lesions, aspiration of contaminated water during near-drowning, and inhalation of organisms. The clinical manifestations of melioidosis are not uniform, and patients can present with pneumonia, skin abscesses, soft tissue abscesses, or osteomyelitis/septic arthritis. Pneumonic melioidosis is presented in over 50% of acute cases of the disease, and disseminated pneumonia is associated with high mortality. Chronic melioidosis usually occurs following acute melioidosis, and relapsing melioidosis can result from the reactivation of a latent B. pseudomallei infection, often due to the withdrawal of antibiotics or the failure to complete prescribed courses of antibiotics (Harland et al., 2007).
4. Microbial Pathogenesis
B. pseudomallei is an "accidental pathogen". It is an environmental organism that has no requirement to pass through an animal host in order to replicate. From the point of view of the bacterium, human infection is an evolutionary "dead end". B. pseudomallei is able to invade cells, polymerise actin and to spread from cell to cell, causing cell fusion and the formation of multinucleate giant cells (Wiki: B. pseudomallei).
5. Host Ranges and Animal Models
B. pseudomallei infects humans and animals and causes the disease melioidosis. It is also capable of infecting plants (Wiki: B. pseudomallei).
Molecule Role Annotation :
The aroC deletion in the resultant mutant, designated A2ΔaroC, was confirmed by PCR, Southern hybridization and failure of the mutant to grow in a defined medium without aromatic compounds. The constructed unmarked aroC mutant of B. pseudomallei is attenuated in both BALB/c and C57Bl/6 mice and is able to confer significant protection in C57Bl/6 mice (Srilunchang et al., 2009).
Molecule Role Annotation :
An asd mutant is highly attenuated in mice. This mutant was also able to protect against acute inhalation melioidosis caused by challenge with wild type B. pseudomallei (Norris et al., 2011).
Molecule Role Annotation :
Flagellin encoding plasmid DNA was injected into Balb/c mice intramuscularly and this elicited both a humoral and a cellular immune response. Subsequent intravenous challenge of the vaccinated Balb/c mice with 10^5CFU of B. pseudomallei resulted in the number of bacterial cells detected in liver and/or spleen being significantly reduced in the flagellin plasmid DNA vaccinated mice. At 7 days subsequent to infection of B. pseudomallei, 5/6 (83%) of flagellin plasmid DNA vaccinated mice had survived (Chen et al., 2006).
Protein Name :
lipoprotein releasing system transmembrane protein
Protein pI :
9.43
Protein Weight :
41147.07
Protein Length :
417
Protein Note :
Similar to Escherichia coli lipoprotein releasing system transmembrane protein LolE SWALL:LOLE_ECOLI (SWALL:P75958) (413 aa) fasta scores: E(): 1.3e-42, 34.54% id in 414 aa, and to Ralstonia solanacearum probable lipoprotein releasing system transmembrane rsc1117 or rs05757 SWALL:Q8Y0C7 (EMBL: AL646062) (416 aa) fasta scores: E(): 1.4e-112, 71.46% id in 417 aa
>YP_108873.1 lipoprotein releasing system transmembrane protein [Burkholderia pseudomallei K96243]
MKLPYEWQIGWRYTRAGKRTTGNGFISFIALVSMLGIALGVAALIVVLSVMNGFQKEVRDRMLSVLAHVE
IFSPTGSMPDWQLTAKEARLNRSVIGAAPYVDAQALLTRQDAVSGVMLRGVEPSLEPQVSDIGKDMKAGA
LTALAPGQFGIVLGNALAGNLGVGVGDKVTLVAPEGTITPAGMMPRLKQFTVVGIFESGHYEYDSTLAMI
DIQDAQALFRLPAPTGVRLRLTDMQKAPQVARELAHTLSGDLYIRDWTQQNKTWFSAVQIEKRMMFIILT
LIIAVAAFNLVSSLVMTVTNKQADIAILRTLGAQPGSIMKIFVVQGVTIGFVGTATGVALGCLIAWSIPW
LIPMIEHAFGVQFLPPSVYFISELPSELVAGDVIKIGVIAFALSALATLYPSWRGAKVRPAEALRYE
Molecule Role :
Protective antigen
Molecule Role Annotation :
LolC was evaluated as an antigen for a vaccine candidate against B. pseudomallei infection. Nonmembrane regions of the B. pseudomallei protein was expressed and purified from Escherichia coli and then evaluated as a vaccine candidate in an established mouse model of B. pseudomallei infection. When delivered with the monophosphoryl lipid A-trehalose dicorynomycolate adjuvant, the protein stimulated antigen-specific humoral and cellular immune responses. Immunization with the LolC protein domain afforded significant protection against a subsequent challenge with B. pseudomallei. LolC provided a greater level of protection when it was administered with immune-stimulating complexes complexed with CpG oligodeoxynucleotide 10103. Immunization with LolC also protected against a subsequent challenge with a heterologous strain of B. pseudomallei, demonstrating the potential utility of this protein as a vaccine antigen for melioidosis (Harland et al., 2007).
Protein Name :
ABC transporter substrate-binding protein
Protein pI :
6.89
Protein Weight :
37606.43
Protein Length :
373
Protein Note :
Similar to Escherichia coli putrescine-binding periplasmic protein precursor PotF or b0854 SWALL:POTF_ECOLI (SWALL:P31133) (370 aa) fasta scores: E(): 3.3e-67, 49.3% id in 357 aa, and to Pseudomonas aeruginosa polyamine transport protein pa0301 SWALL:Q9I6J0 (EMBL: AE004468) (365 aa) fasta scores: E(): 6.3e-69, 49.59% id in 367 aa. Possible alternative translational start site
Molecule Role Annotation :
PotF was evaluated as an antigen for a vaccine candidate against B. pseudomallei infection. Nonmembrane regions of the B. pseudomallei protein was expressed and purified from Escherichia coli and then evaluated as a vaccine candidate in an established mouse model of B. pseudomallei infection. When delivered with the monophosphoryl lipid A-trehalose dicorynomycolate adjuvant, the protein stimulated antigen-specific humoral and cellular immune responses. Immunization with the PotF protein domain afforded significant protection against a subsequent challenge with B. pseudomallei (Harland et al., 2007).
Protein Name :
phosphoribosylaminoimidazole synthetase
Protein pI :
4.98
Protein Weight :
33766.88
Protein Length :
351
Protein Note :
Also known as purGcatalyzes the formation of 1-(5-phosphoribosyl)-5-aminoimidazole from 2-(formamido)-N1-(5-phosphoribosyl)acetamidine and ATP in purine biosynthesis
Protein Name :
phosphoribosylglycinamide formyltransferase
Protein pI :
6.08
Protein Weight :
21138.36
Protein Length :
220
Protein Note :
glycinamide ribonucleotide transformylase; GAR Tfase; catalyzes the synthesis of 5'-phosphoribosylformylglycinamide from 5'-phosphoribosylglycinamide and 10-formyltetrahydrofolate; PurN requires formyl folate for the reaction unlike PurT which uses formate
Molecule Role Annotation :
Although 30:93a purN -immunized mice were challenged with a 10-fold higher dose of WT E8, mice were strongly protected and showed no signs of clinical illness until the experiment was terminated (Breitbach et al., 2008).
>WP_004530590.1 MULTISPECIES: YscQ/HrcQ family type III secretion apparatus protein [Burkholderia]
MSARYTLFRRVAPAELPLYRRARALRAAGEHAALRTIAPPRGYAALRATWRGVEHDGWVDLDDLMRRRYP
ALGALAWRALDRRYALDLLSGRDAAAELPAPPGGWAHVRLVDLVERALPAEPLLCFDTPGRARALFRAFP
DEAPAARAVADIGGVPLTMRFAIGTARLPLALLPAVAPGDVLLVCAPRNVVRIGARALCEFCCEGENIML
NEPLADSAIDALHDASHDASHDEPTAAHAPPAFDIDALPVTLEFVLHDERVTVAQLAGCHPGMVLPLRGA
PGEVTIRANGQPFGRGELIQVGEQLAVEVKALWRAKPAACDGE
Molecule Role :
Protective antigen
Molecule Role Annotation :
Subpopulations of B. pseudomallei-reactive T cells were responsive to BopE, a type III secretion system (TTSS) effector protein, and to a lesser extent to BipD, a TTSS translocator protein.(Haque et al., 2006)
Molecule Role Annotation :
IFN-gamma plays a critical role in Th1 type immune response. It is important for protection against infections by various viruses and intracellular bacteria.
Additional Molecule Role :
Vaximmutor
Additional Molecule Role Annotation :
The experimental data demonstrated that three time vaccinations with BCG in BALB/c mice induced strong TB Ag-specific IFN-gamma immune responses in splenocytes (Wang et al., 2009).
Vaccination Protocol:
Six-week-old female Balb/c mice from groups 1–3 were injected intramuscularly (i.m.) with pcDNA3/fliC in PBS (50, 100 or 150 μg); whereas those from group 4 (the negative control) were injected (i.m) with vector DNA(150 μg; pcDNA3) in PBS, whilst those from group 5 (the positive control) were injected subcutaneously with recombinant flagellin antigens (50 μg) emulsified in complete Freund's adjuvant. Each animal from group 5 was subsequently boosted with the same dose of flagellin in incomplete Freund's adjuvant 14 days subsequent to the initial flagellin injection. The animals in groups 1–4 were boosted twice with an identical dose of plasmid DNA, once at 7 days and then again at 14 days after the initial injection (Chen et al., 2006).
Challenge Protocol:
The immunized mice were infected via the tail vein with 105 CFU of mixed B. pseudomallei suspended in sterile PBS (50 μl). As control groups, the mice received either sterile PBS or vector DNA (Chen et al., 2006).
Efficacy:
Subsequent intravenous challenge of the vaccinated Balb/c mice with 10(5)CFU of B. pseudomallei resulted in the number of bacterial cells detected in liver and/or spleen being significantly reduced in the flagellin plasmid DNA vaccinated mice. At 7 days subsequent to infection of B. pseudomallei, 5/6 (83%) of flagellin plasmid DNA vaccinated mice had survived (Chen et al., 2006).
Host Gene Response of
Ifng (Interferon gamma)
Gene Response:
Mice spleen cells were collected after an eight-week immunization. The up-regulation of IFN-γ production among the mice immunized with pcDNA3/fliC was significantly greater than among the mice either immunized with recombinant flagellin or vaccinated with vector DNA only (Chen et al., 2006).
Vaccination Protocol:
Female 5- to 6-week-old BALB/c mice were immunized with the purified recombinant LolC protein given with adjuvant (Harland et al., 2007).
Challenge Protocol:
Mice immunized with the LolC protein or appropriate controls were challenged with B. pseudomallei K96243 on day 70 (Harland et al., 2007).
Efficacy:
The recombinant LolC protein afforded significant protection against the B. pseudomallei challenge (Harland et al., 2007).
Vaccination Protocol:
Female 5- to 6-week-old BALB/c mice were immunized with the purified recombinant PotF protein given with adjuvant (Harland et al., 2007).
Challenge Protocol:
Mice immunized with the PotF protein or appropriate controls were challenged with B. pseudomallei K96243 on day 70 (Harland et al., 2007).
Efficacy:
Immunization with the PotF protein domain afforded significant protection against a subsequent challenge with B. pseudomallei (Harland et al., 2007).
An unmarked aroC deletion mutant of B. pseudomallei strain A2 was constructed using a sucrose counter-selection strategy. The aroC deletion in the resultant mutant, designated A2DeltaaroC, was confirmed by PCR, Southern hybridization and failure of the mutant to grow in a defined medium without aromatic compound (Srilunchang et al., 2009).
f. Immunization Route
Intraperitoneal injection (i.p.)
g.
Mouse Response
Persistence:
Compared to the parental wild type strain, A2DeltaaroC was highly attenuated for virulence following intraperitoneal introduction into BALB/c and C57BL/6 mice (Srilunchang et al., 2009).
Efficacy:
C57BL/6 mice immunized intraperitoneally with A2DeltaaroC were significantly protected against a challenge dose of 6,000 cfu (20 x LD50) (Srilunchang et al., 2009).
Persistence:
A purN mutant was attenuated in mice, as mice did not show any clinical symptoms of illness (Breitbach et al., 2008).
Efficacy:
A purN induced strong protection in mice from challenge with wild type B. pseudomallei (Breitbach et al., 2008).
V. References
1. Breitbach et al., 2008: Breitbach K, Köhler J, Steinmetz I. Induction of protective immunity against Burkholderia pseudomallei using attenuated mutants with defects in the intracellular life cycle. Transactions of the Royal Society of Tropical Medicine and Hygiene. 2008; 102 Suppl 1; S89-94. [PubMed: 19121696].
2. Casey et al., 2016: Casey WT, Spink N, Cia F, Collins C, Romano M, Berisio R, Bancroft GJ, McClean S. Identification of an OmpW homologue in Burkholderia pseudomallei, a protective vaccine antigen against melioidosis. Vaccine. 2016; 34(23); 2616-2621. [PubMed: 27091689].
3. Chen et al., 2006: Chen YS, Hsiao YS, Lin HH, Yen CM, Chen SC, Chen YL. Immunogenicity and anti-Burkholderia pseudomallei activity in Balb/c mice immunized with plasmid DNA encoding flagellin. Vaccine. 2006; 24(6); 750-758. [PubMed: 16169637].
4. Druar et al., 2008: Druar C, Yu F, Barnes JL, Okinaka RT, Chantratita N, Beg S, Stratilo CW, Olive AJ, Soltes G, Russell ML, Limmathurotsakul D, Norton RE, Ni SX, Picking WD, Jackson PJ, Stewart DI, Tsvetnitsky V, Picking WL, Cherwonogrodzky JW, Ketheesan N, Peacock SJ, Wiersma EJ. Evaluating Burkholderia pseudomallei Bip proteins as vaccines and Bip antibodies as detection agents. FEMS immunology and medical microbiology. 2008; 52(1); 78-87. [PubMed: 17995960].
5. Gourlay et al., 2015: Gourlay LJ, Thomas RJ, Peri C, Conchillo-Solé O, Ferrer-Navarro M, Nithichanon A, Vila J, Daura X, Lertmemongkolchai G, Titball R, Colombo G, Bolognesi M. From crystal structure to in silico epitope discovery in the Burkholderia pseudomallei flagellar hook-associated protein FlgK. The FEBS journal. 2015; 282(7); 1319-1333. [PubMed: 25645451].
6. Haque et al., 2006: Haque A, Chu K, Easton A, Stevens MP, Galyov EE, Atkins T, Titball R, Bancroft GJ. A live experimental vaccine against Burkholderia pseudomallei elicits CD4+ T cell-mediated immunity, priming T cells specific for 2 type III secretion system proteins. The Journal of infectious diseases. 2006; 194(9); 1241-1248. [PubMed: 17041850].
7. Harland et al., 2007: Harland DN, Chu K, Haque A, Nelson M, Walker NJ, Sarkar-Tyson M, Atkins TP, Moore B, Brown KA, Bancroft G, Titball RW, Atkins HS. Identification of a LolC homologue in Burkholderia pseudomallei, a novel protective antigen for melioidosis. Infection and immunity. 2007; 75(8); 4173-4180. [PubMed: 17517877].
8. Harland et al., 2007: Harland DN, Chu K, Haque A, Nelson M, Walker NJ, Sarkar-Tyson M, Atkins TP, Moore B, Brown KA, Bancroft G, Titball RW, Atkins HS. Identification of a LolC homologue in Burkholderia pseudomallei, a novel protective antigen for melioidosis. Infection and immunity. 2007; 75(8); 4173-4180. [PubMed: 17517877].
9. Nelson et al., 2004: Nelson M, Prior JL, Lever MS, Jones HE, Atkins TP, Titball RW. Evaluation of lipopolysaccharide and capsular polysaccharide as subunit vaccines against experimental melioidosis. Journal of medical microbiology. 2004; 53(Pt 12); 1177-1182. [PubMed: 15585494].
10. Norris et al., 2011: Norris MH, Propst KL, Kang Y, Dow SW, Schweizer HP, Hoang TT. The Burkholderia pseudomallei {Delta}asd mutant exhibits attenuated intracellular infectivity and imparts protection against acute inhalation melioidosis in mice. Infection and immunity. 2011; ; . [PubMed: 21807903].
11. Srilunchang et al., 2009: Srilunchang T, Proungvitaya T, Wongratanacheewin S, Strugnell R, Homchampa P. Construction and characterization of an unmarked aroC deletion mutant of Burkholderia pseudomallei strain A2. The Southeast Asian journal of tropical medicine and public health. 2009; 40(1); 123-130. [PubMed: 19323044].
12. Tippayawat et al., 2009: Tippayawat P, Saenwongsa W, Mahawantung J, Suwannasaen D, Chetchotisakd P, Limmathurotsakul D, Peacock SJ, Felgner PL, Atkins HS, Titball RW, Bancroft GJ, Lertmemongkolchai G. Phenotypic and functional characterization of human memory T cell responses to Burkholderia pseudomallei. PLoS neglected tropical diseases. 2009; 3(4); e407. [PubMed: 19352426].
14. Woo et al., 2001: Woo PC, Leung PK, Wong SS, Ho PL, Yuen KY. groEL encodes a highly antigenic protein in Burkholderia pseudomallei. Clinical and diagnostic laboratory immunology. 2001; 8(4); 832-836. [PubMed: 11427437].
