Structure of Streptococcus agalactiae tip pilin GBS104: a model for GBS pili assembly and host interactions
- UNESCO Regional Centre for Biotechnology (RCB), Gurgaon 122 016, Haryana (India)
- University of Texas Health Science Center, Houston, TX 77030 (United States)
- San Diego State University, 5500 Campanile Drive, San Diego, CA 92182 (United States)
- University of Alabama at Birmingham, Birmingham, AL 35294 (United States)
The crystal structure of a 75 kDa central fragment of GBS104, a tip pilin from the 2063V/R strain of Streptococcus agalactiae (group B streptococcus; GBS), is reported. The crystal structure of a 75 kDa central fragment of GBS104, a tip pilin from the 2063V/R strain of Streptococcus agalactiae (group B streptococcus; GBS), is reported. In addition, a homology model of the remaining two domains of GBS104 was built and a model of full-length GBS104 was generated by combining the homology model (the N1 and N4 domains) and the crystal structure of the 75 kDa fragment (the N2 and N3 domains). This rod-shaped GBS104 model is constructed of three IgG-like domains (the N1, N2 and N4 domains) and one vWFA-like domain (the N3 domain). The N1 and N2 domains of GBS104 are assembled with distinct and remote segments contributed by the N- and C-termini. The metal-binding site in the N3 domain of GBS104 is in the closed/low-affinity conformation. Interestingly, this domain hosts two long arms that project away from the metal-binding site. Using site-directed mutagenesis, two cysteine residues that lock the N3 domain of GBS104 into the open/high-affinity conformation were introduced. Both wild-type and disulfide-locked recombinant proteins were tested for binding to extracellular matrix proteins such as collagen, fibronectin, fibrinogen and laminin, and an increase in fibronectin binding affinity was identified for the disulfide-locked N3 domain, suggesting that induced conformational changes may play a possible role in receptor binding.
- OSTI ID:
- 22351290
- Journal Information:
- Acta Crystallographica. Section D: Biological Crystallography, Vol. 69, Issue Pt 6; Other Information: PMCID: PMC3663123; PMID: 23695252; PUBLISHER-ID: dw5037; OAI: oai:pubmedcentral.nih.gov:3663123; Copyright (c) International Union of Crystallography 2013; Country of input: International Atomic Energy Agency (IAEA); ISSN 0907-4449
- Country of Publication:
- Denmark
- Language:
- English
Similar Records
Structural basis for DNA recognition by STAT6
Novel substrate specificity of glutathione synthesis enzymes from Streptococcus agalactiae and Clostridium acetobutylicum