Other Proteins

The p39 protein, or Basic membrane protein A, is one of the immunogenic cell membrane components of Borrelia burgdorferi, the spirochete carried by Ixodes ticks. The spirochete migrates from the tick midgut during feeding to its salivary glands and are thus transmitted to the mammal host. This transition may be facilitated by changes in expression of some B. burgdorferi genes. It is believed that expression of the various proteins associated with the spirochete may be regulated by the changes in tick life cycle, changes in conditions during tick feeding (such as temperature, pH, and nutrients) and/or in coordination with the course of infection of the mammal host. BmpA is expressed during the invasion of the spirochete and in the evolution of the arthritis of Lyme disease in mammals. It belongs to the BMP lipoprotein family. The major products of the B. burgdorferi basic membrane protein (bmp) A/B operon that are induced in murine and human joints possess inflammatory properties.

CRASP-1, or Complement Regulator-Acquiring Surface Protein 1, is a multifunctional protein of Lyme disease-causing B. burgdorferi that binds to several human extracellular matrix proteins and plasminogen, including factor H (resulting in inhibition of complement activation in mammals) and Human Bone Morphogenic Protein 2. These interactions may contribute to adhesion, bacterial colonization, and organ tropism and may allow dissemination of B. burgdorferi in the host. B. burgdorferi spirochetes express up to 5 complement regulator-acquiring surface proteins. Multiple copies of sequences analagous to CRASP-1 genes have been detected in Borrelia plasmids. Borrelia species contain a large number of plasmids, of linear and circular, some of which appear to repeat sequences or contain fragments of other genes. These regions may serve as potentially usable information for the survival of Borrelia in its multiple environments during its life cycle. In addition, the sequence for CRASP-1

CRASP-2 (Complement Regulator-Acquiring Surface Protein 2) of Borrelia burgdorferi binds FHL-1 and factor H binding protein in a distinct way. It may be predominantly expressed by serum-resistant Borrelia strains. Borrelia burgdorferi sensu lato has the ability to evade immune systems to persist in a variety of vertebrate hosts. This activity is dependent on a number of factors. Some Borrelia species bind host-derived fluid-phase immune regulators FHL-1 and factor H to their surface via complement regulator-acquiring surface proteins (CRASPs). Factor H and FHL-1 serve as cofactors for factor I, a serine protease that cleaves complement component 3b (C3b) directly on the cell surface and thereby confers resistance of spirochetes to complement-mediated lysis. It is possible that because of discontinuous binding regions in the factor H/FHL-1, long distance interaction may be involved in binding of both immune regulators. Putative coiled-coil structural elements may be important in

Surface Lipoprotein p27 of Borrelia burgdorferi is a surface-exposed lipoprotein that has been shown (by Western blot and Northern blot) to be expressed in the European B. burgdorferi strain B29, but not in the American strain B31. Cell envelope proteins of bacterial pathogens play important roles in the host-parasite interactions that occur during infection, including cell adherence, cell invasion, and immune cell activation or evasion. p27 is a basic protein of 248 amino acids with a typical prokaryotic leader sequence of 17 amino acid residues at the N-terminus of the proposed translation product. The p27 gene is located on a linear plasmid of a size of approximately 55 kb. Borrelia spirochetes are unique among diderm bacteria in their abundance of surface-displayed lipoproteins, some of which play important roles in the pathogenesis of Lyme disease and relapsing fever. There is evidence that Borrelia lipoproteins are specifically targeted to the bacterial surface, but that the

Variable Lipoprotein Surface-Exposed protein, or VlsE, is a lipoprotein on the surface of the Lyme Disease spirochete Borrelia burgdorferi, detectable during all its life stages. It can exist as many different isoforms. VlsE has variable regions (VRs) and invariable regions (IRs). Some IRs are anchored in the outer membrane of the bacteria and some are antigens exposed on the membrane surface. Replacement of the VR by Borrelia within days of being transferred to a mammalian host presents new surface antigens to the host immune system, and helps Borrelia avoid a strong reaction by host immune systems. The VlsE is apparently not modified as much in the tick or in the rodent vector, when compared to in the mammal host. Several putative envelope proteins of B. burgdorferi appear to be expressed only in the infected mammalian host. The VRs are antigenic, irregularly shaped loops on the bacterial surface which may help to hide both membrane-incorporated and surface portions of adjacen

Host Cell Protein Lysate was prepared by solubilizing mock induced E. coli cells. Host Cell Proteins are process-related impurities derived from a host cell expression system that may be present in trace amounts in a final drug substance. HCP Antibodies are used to detect impurities in biologically-based therapeutics. Detecting impurities often unseen by 1-D electrophoresis, a 2D electrophoresis western blot analysis delivers more complete insight into the immunocoverage of protein components of the host cell lysate.

GST (Glutathione-S-Transferase) is a 26kDa protein. GST is a fusion protein in an array of prokaryotic expression vectors, including the pGEX family of vectors. Anti-GST antibodies GST will detect the expressed GST protein or a GST-fusion protein, and can be utilized for immuno-purification of GST-fusion proteins.

Secreted as part of the adaptive immune response by plasma B cells, immunoglobulin G constitutes 75% of serum immunoglobulins. Immunoglobulin G binds to viruses, bacteria, as well as fungi and facilitates their destruction or neutralization via agglutination (and thereby immobilizing them), activation of the compliment cascade, and opsonization for phagocytosis. The whole IgG molecule possesses both the F(c) region, recognized by high-affinity Fc receptor proteins, as well as the F(ab) region possessing the epitope-recognition site. Both heavy and light chains of the antibody molecule are present.

Secreted as part of the adaptive immune response by plasma B cells, immunoglobulin G constitutes 75% of serum immunoglobulins. Immunoglobulin G binds to viruses, bacteria, as well as fungi and facilitates their destruction or neutralization via agglutination (and thereby immobilizing them), activation of the compliment cascade, and opsonization for phagocytosis. This product possesses the F(ab')2 fragment, recognized by the two F(ab) fragments yielded from the digestion of the antibody below the disulfide bond hinge region.