Decorin-binding adhesins from Borrelia burgdorferi.
Lyme disease is a tick-transmitted infection caused by the spirochete Borrelia burgdorferi. Ticks deposit B. burgdorferi into the dermis of the host, where they eventually become associated with collagen fibres. We demonstrated previously that B. burgdorferi is unable to bind collagen, but can bind the collagen-associated proteoglycan decorin and expresses decorin-binding proteins (Dbps). We have now cloned and sequenced two genes encoding the proteins, DbpA and DbpB, which have a similar structure, as revealed by circular dichroism (CD) spectroscopy of recombinant proteins. Competition experiments revealed a difference in binding specificity between DbpA and DbpB. Western blot analysis of proteinase K-treated intact B. burgdorferi and transmission electron microscopy studies using antibodies raised against recombinant Dbps demonstrated that these proteins are surface exposed. DbpA effectively inhibits the attachment of B. burgdorferi to a decorin substrate, whereas DbpB had a marginal effect, suggesting a difference in substrate specificity between the two Dbps. Polystyrene beads coated with DbpA adhered to a decorin-containing extracellular matrix produced by cultured skin fibroblasts, whereas beads coated with OspC did not. Taken together, these data suggest that Dbps are adhesins of the MSCRAMM (microbial surface component-recognizing adhesive matrix molecule) family, which mediate B. burgdorferi attachment to the extracellular matrix of the host.
Guo
B P
BP
Albert B. Alkek Institute of Biosciences and Technology and the Department of Biochemistry and Biophysics, Texas A & M University, Houston 77030, USA.
Brown
E L
EL
Dorward
D W
DW
Rosenberg
L C
LC
Höök
M
M
D018829:Adhesins, Bacterial / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D001422:Bacterial Adhesion; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins; D001483:Base Sequence; D015748:Borrelia burgdorferi Group / Q000235:genetics / Q000378:metabolism*; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D002478:Cells, Cultured; D003001:Cloning, Molecular; D004269:DNA, Bacterial; D058575:Decorin; D005109:Extracellular Matrix / Q000378:metabolism; D016326:Extracellular Matrix Proteins; D005347:Fibroblasts / Q000382:microbiology; D006801:Humans; D008969:Molecular Sequence Data; D011509:Proteoglycans / Q000378:metabolism*; D011817:Rabbits; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D012867:Skin / Q000166:cytology
D018829:Adhesins, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D002352:Carrier Proteins; C546878:DCN protein, human; D004269:DNA, Bacterial; C112557:DdpB protein, Borrelia burgdorferi; D058575:Decorin; D016326:Extracellular Matrix Proteins; D011509:Proteoglycans; D011993:Recombinant Fusion Proteins