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 contains a repeated sequence folded into a stable stem loop structure typical of RNA genes.
MBP-fusion protein corresponding to Borrelia burgdorferi CRASP-1 protein.