Borrelia Bavariensis VlsE1

Borrelia Bavariensis is a species within the Borrelia genus, which belongs to the spirochete phylum. This genus is known for causing borreliosis, a zoonotic, vector-borne disease primarily transmitted by ticks and, in some cases, by lice. Among the 36 known species of Borrelia, 12 are recognized for causing Lyme disease or borreliosis. The primary species responsible for Lyme disease include Borrelia burgdorferi, Borrelia afzelii, and Borrelia garinii .

Members of the Borrelia genus possess a linear chromosome approximately 900 kilobase pairs (kbp) in length. Additionally, they have an array of both linear and circular plasmids ranging from 5 to 220 kbp. These plasmids are atypical compared to most bacterial plasmids, as they contain numerous paralogous sequences, a significant number of pseudogenes, and, in some cases, essential genes. Some plasmids also exhibit features suggesting they are prophages .

The VlsE1 (Variable major protein-like sequence E1) is a key protein in Borrelia species. It plays a crucial role in the immune evasion mechanisms of the bacteria. The VlsE1 protein undergoes antigenic variation, allowing the bacteria to evade the host’s immune response. This variation is achieved through recombination events within the vlsE gene, leading to the expression of different VlsE1 variants on the bacterial surface .

Recombinant Borrelia Bavariensis VlsE1 is produced in Escherichia coli (E. coli) and is a non-glycosylated polypeptide chain with a calculated molecular mass of 28 kDa. It is expressed with a 6x His tag at the N-terminus and purified using proprietary chromatographic techniques. The recombinant VlsE1 is supplied in a sterile filtered clear solution and formulated in 20mM HEPES buffer (pH 7.6), 250mM NaCl, and 20% glycerol .

Recombinant VlsE1 is used in various immunological assays, including Western blotting with patient samples and immunodot tests with positive and negative samples. It binds to IgG- and IgM-type human antibodies, making it a valuable tool for serodiagnosis of Lyme borreliosis. The protein is stable when stored at 4°C for short-term use (2-4 weeks) and at -20°C for long-term storage. It is important to avoid multiple freeze-thaw cycles to maintain its stability .

The ZEUS Borrelia VlsE1/pepC10 assay, which utilizes recombinant VlsE1, has shown comparable diagnostic parameters to the C6-ELISA, a commonly used assay for Lyme borreliosis. The VlsE1/pepC10 assay has demonstrated potentially improved specificity in sera with cross-reactive antibodies, making it a useful tool for the serodiagnosis of Lyme borreliosis in Europe .