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Veterinary bacteriology: information about important bacteria
Veterinary bacteriology

Species/Subspecies: Burkholderia mallei
Categories: Zoonotic; motile; notifiable diseases and bacteria
Etymology: Genus name: named after the American bacteriologist W.H. Burkholder.
Species epithet: refers to the disease (glanders, which in latin is "malleus").
Significance:Glanders has been globally distributed, but is now extinct in most developed countries. Sporadic cases occur in Africa, Asia, the Middle East, India, Pakistan, China, Central and South America. Rods is considered to be endemic in Mongolia.
  [Very important]   
Alternative Species Name(s):Pseudomonas mallei
Type Strain: NBL 7 = ATCC 23344 = NCTC 12938.
Macromorphology (smell): Grey translucent colonies without smell or pigments. Does not give hemolysis on blood agar.
Micromorphology: Small coccoid and nonmotile rods (0.5-1 x 1.5-3 µm) with rounded ends and apperaring in pair or bundles. B. mallei lacks flagella in contrast to other members of genus Burkholderia. However, this bacterium can move inside a host cell by actin-based motility.
Gram +/Gram -:G-
Metabolism: Facultatively anaerobic (because it kan can utilize NO3- as final electron acceptor in the absence of oxygen).
Fermentation of carbohydrates: Burkholderia spp. do not ferment carbohydrates.
Spec. Char.:
HostsDiseaseClinical picture
Horses and other equidsGlandersAcute form: fever, mucopurulent nasal discharge, respiratory disorder and septicaemia.
Chronic form:
*Pulmonary, small nodules in the respiratory tract, weight loss.
*Contagious (Farcy), lymphangitis, ulcers along lymphatic pathways.
Healed ulcers could form "star-shaped" scars.
Asymptomatic carriers occurs.
HumansGlandersUlceration of the respiratory mucosa and eruption of nodules on the skin. Transmitted to humans by contact with infected animals.
CarnivoresGlandersNodules and ulcers in the nasal passages, conjunctivae, and deeper in the respiratory tract. Swelling of the lymph nodes, dyspnea and nonspecific signs (e.g., anorexia, depression). May become infected by eating infected meat.
Virulence Factors: Capsule, sekretionssystem av typ III och IV as well as adhesion proteins, fimbria and system for quorum sensing.
Genome Sequence:
Acc-noStrainSize (bp)Genome
NC_006348 and NC_006349 ATCC 23344 5 835 527 (2c + ?) 
Chrom. I (3 510 148 bp) and chrom. II (2 325 379 bp), respectively.

16S rRNA Seq.:
Acc-noStrainNumber of NTOperon
AF110187 NCTC 10260 1488 
Two rRNA genes in Chrom. I and two in chrom. II.

About 100 species have been described within genus Burkholderia, which is related to genus Taylorella. The two species of genus Burkholderia, which have beebn included in VetBact, are very closely related.
Legislation: In Sweden glanders is notifiable to the Swedish Board of Agriculture. Burkholderia mallei belongs to category B as a potential bioterrorism agent according to NIAID.
Comment:Glanders is highly contagious, only a few organisms are needed and it is easily spread by aerosol.


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