3ipk

Crystal Structure of A3VP1 of AgI/II of Streptococcus mutans

spinqualitylabelsall models 3ipk, resolution 2.04Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 3ipk is a 2 chain structure with sequence from Streptococcus mutans. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 2.04Å Ligands: CA, PMS, SO4 Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function C9E3B4_STRMG Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed Streptococcus mutans antigen I/II (AgI/II) is a cell surface-localized protein adhesin that interacts with salivary components within the salivary pellicle. AgI/II contributes to virulence and has been studied as an immunological and structural target, but a fundamental understanding of its underlying architecture has been lacking. Here we report a high-resolution (1.8 A) crystal structure of the A(3)VP(1) fragment of S. mutans AgI/II that demonstrates a unique fibrillar form (155 A) through the interaction of two noncontiguous regions in the primary sequence. The A(3) repeat of the alanine-rich domain adopts an extended alpha-helix that intertwines with the P(1) repeat polyproline type II (PPII) helix to form a highly extended stalk-like structure heretofore unseen in prokaryotic or eukaryotic protein structures. Velocity sedimentation studies indicate that full-length AgI/II that contains three A/P repeats extends over 50 nanometers in length. Isothermal titration calorimetry revealed that the high-affinity association between the A(3) and P(1) helices is enthalpically driven. Two distinct binding sites on AgI/II to the host receptor salivary agglutinin (SAG) were identified by surface plasmon resonance (SPR). The current crystal structure reveals that AgI/II family proteins are extended fibrillar structures with the number of alanine- and proline-rich repeats determining their length. Elongated fibrillar structure of a streptococcal adhesin assembled by the high-affinity association of {alpha}- and PPII-helices.,Larson MR, Rajashankar KR, Patel MH, Robinette RA, Crowley PJ, Michalek S, Brady LJ, Deivanayagam C Proc Natl Acad Sci U S A. 2010 Mar 15. PMID:20231452 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

Proteopedia Page Contributors and Editors (what is this?)

OCA