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Veterinary bacteriology: information about important bacteria
Veterinary bacteriology

Species/Subspecies: Brucella melitensis
Categories: Zoonotic; notifiable diseases and bacteria
Etymology: Genus name: named after Sir David Bruce, who first identified the organism, which causes brucellosis.
Species epithet: Refers to the island of Malta (Melita), where the organism was first found.
Significance:  [Very important]   
Type Strain: 16M = ATCC 23456 = NCTC 100
Macromorphology (smell): Pale honey coloured transparant colonies, which do not give hemolysis on blood agar.
Micromorphology: Non-motile cocci or short rods
Gram +/Gram -:G-
Metabolism: Aerobic
Other Enzymes: Urease +
Fermentation of carbohydrates: Most Brucella spp. do not produce acid by fermentation of carbohydrates.
Spec. Char.:
Special Media:
Disease:Brucellosis. Malta fever. The disease is a zoonosis.
HostsDiseaseClinical picture
Sheep and goatsBrucelloisisAbortion (mostly last trimester), stillbirth, reduce milk yield, retained placenta, purulent vaginal discharge. In males orchitis, epididymitis and infertility
CattleBrucelloisisAbortion, reproductive losses, orchitis, epididymitis, arthritis and hygromas
HumansBrucelloisis, Malta feverDiverse symptoms from asymptomatic to flu-like signs, fever, chills, headache, malaise, back pain, myalgia and lymphadenopathy.
Negligible human mortality
Most common species of brucellosis in humans
Genome Sequence:
Acc-noStrainSize (bp)Genome
NC_003317 and NC_003318 16M 3 294 931 (2c + 0) 
Chrom. I (2 117 144 bp) and chrom. II (1 177 787 bp), respectively.
Totally two strains have been sequenced, but plasmids have not been reported.

16S rRNA Seq.:
Acc-noStrainNumber of NTOperon
L26166 (T) 1405 
Two rRNA genes in chrom. I and one in chrom. II.

Brucella melitensis  
About 25 species have been described within genus Brucella and this genus is closely related to genus Bartonella. From a phylogenetic point of view, B. abortus, B. canis, B. ceti, B. melitensis, B. neotome, B. ovis, B. pinnipedialis and B. suis represent the same species (B. melitensis), but due to different host specificities, they have been affiliated with different species.
Legislation: Brucella melitensis belongs to category B as a potential bioterrorism agent according to NIAID.
Comment:May penetrate intact skinn. in Sweden brucellosis is notifiable to the Swedish Board of Agriculture and is governed by the epizootic diseases law.
Link: Epiwebb - om epizootisjukdomar [in Swedish]

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