4ann

Crystal Structure Staphylococcus aureus ESSB cytoplasmic fragmentCrystal Structure Staphylococcus aureus ESSB cytoplasmic fragment

Structural highlights 4ann is a 1 chain structure with sequence from Staphylococcus aureus subsp. aureus NCTC 8325. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 1.05Å Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function ESSB_STAA8 Component of the type VII secretion system (Ess) (Probable). Required for the secretion of EsxA and EsxB (By similarity).[UniProtKB:P0C053] Publication Abstract from PubMed The type VII protein translocation/secretion system, unique to Gram-positive bacteria is a key virulence determinant in Staphylococcus aureus. We aim to characterise the architecture of this secretion machinery and now describe a study of S. aureus EssB, a 52-kDa bitopic membrane protein essential for secretion of the ESAT-6-family-proteins, the prototypic substrate of Type VII secretion. Full-length EssB was heterologously expressed in Escherichia coli, solubilised from the bacterial membrane, purified to homogeneity and shown to be dimeric. A C-terminal truncation, EssBC, and two soluble fragments termed EssB-N and EssB-C, predicted to occur on either side of the cytoplasmic membrane, have been successfully purified in recombinant form, characterised and together with the full-length protein used in crystallisation trials. EssB-N, the 25 kDa N-terminal cytoplasmic fragment, gave well-ordered crystals and we report the structure, determined by single-wavelength anomalous diffraction (SAD) targeting an SeMet derivative, refined to atomic (1.05 A) resolution. EssB-N is dimeric in solution but crystallises as a monomer and displays a fold composed of two globular domains separated by a cleft. The structure is related to that of Ser/Thr protein kinases and our study identifies that the type VII secretion system exploits and re-uses a stable modular entity and fold that has evolved to participate in protein-protein interactions in a similar fashion to the catalytically inert pseudokinases. Characterisation of Staphylococcus aureus EssB, an integral membrane component of the Type VII secretion system; atomic resolution crystal structure of the cytoplasmic segment.,Zoltner M, Fyfe PK, Palmer T, Hunter WN Biochem J. 2012 Oct 25. PMID:23098276 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

spinqualitylabelsall models 4ann, resolution 1.05Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image