1YWM

Crystal structure of the N-terminal domain of group B Streptococcus alpha C protein

1YWM の概要

• エントリーDOI: 10.2210/pdb1ywm/pdb
• 分子名称: C protein alpha-antigen, (2R,3S)-1,4-DIMERCAPTOBUTANE-2,3-DIOL, GLYCEROL, ... (4 entities in total)
• 機能のキーワード: beta sandwich, fibronectin fold, antiparallel three-helix bundle, surface active protein
• 由来する生物種: Streptococcus agalactiae
• 細胞内の位置: Secreted, cell wall; Peptidoglycan-anchor (Potential): Q02192
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 22361.12

構造登録者

Auperin, T.C.,Bolduc, G.R.,Baron, M.J.,Heroux, A.,Filman, D.J.,Madoff, L.C.,Hogle, J.M. (登録日: 2005-02-18, 公開日: 2005-03-08, 最終更新日: 2024-04-03)

主引用文献

Auperin, T.C.,Bolduc, G.R.,Baron, M.J.,Heroux, A.,Filman, D.J.,Madoff, L.C.,Hogle, J.M.
Crystal structure of the N-terminal domain of the group B streptococcus alpha C protein.
J.Biol.Chem., 280:18245-18252, 2005

PubMed Abstract: Group B Streptococcus (GBS) is the leading cause of bacterial pneumonia, sepsis, and meningitis among neonates and an important cause of morbidity among pregnant women and immunocompromised adults. Invasive diseases due to GBS are attributed to the ability of the pathogen to translocate across human epithelial surfaces. The alpha C protein (ACP) has been identified as an invasin that plays a role in internalization and translocation of GBS across epithelial cells. The soluble N-terminal domain of ACP (NtACP) blocks the internalization of GBS. We determined the 1.86-A resolution crystal structure of NtACP comprising residues Ser(52) through Leu(225) of the full-length ACP. NtACP has two domains, an N-terminal beta-sandwich and a C-terminal three-helix bundle. Structural and topological alignments reveal that the beta-sandwich shares structural elements with the type III fibronectin fold (FnIII), but includes structural elaborations that make it unique. We have identified a potential integrin-binding motif consisting of Lys-Thr-Asp(146), Arg(110), and Asp(118). A similar arrangement of charged residues has been described in other invasins. ACP shows a heparin binding activity that requires NtACP. We propose a possible heparin-binding site, including one surface of the three-helix bundle, and nearby portions of the sandwich and repeat domains. We have validated this prediction using assays of the heparin binding and cell-adhesion properties of engineered fragments of ACP. This is the first crystal structure of a member of the highly conserved Gram-positive surface alpha-like protein family, and it will enable the internalization mechanism of GBS to be dissected at the atomic level.

PubMed: 15753100
DOI: 10.1074/jbc.M412391200

実験手法

X-RAY DIFFRACTION (1.86 Å)