5UVD

Crystal structure of an antigenic nucleotidyltransferase-like protein from Paracoccidioides brasiliensis

5UVD の概要

• エントリーDOI: 10.2210/pdb5uvd/pdb
• 分子名称: Nucleotidyltransferase-like protein, MAGNESIUM ION (3 entities in total)
• 機能のキーワード: antigen, putative nucleotidyltransferase, transferase
• 由来する生物種: Paracoccidioides brasiliensis (strain Pb18)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 24830.15

構造登録者

Nagem, R.A.P.,Costa, M.A.F.,Rodrigues, F.T.G.,Coitinho, J.B.C. (登録日: 2017-02-20, 公開日: 2018-01-31, 最終更新日: 2024-03-06)

主引用文献

Coitinho, J.B.,Costa, M.A.F.,Melo, E.M.,Morais, E.A.,de Andrade, L.G.A.,da Rocha, A.M.,de Magalhaes, M.T.Q.,Favaro, D.C.,Bleicher, L.,Pedroso, E.R.P.,Goes, A.M.,Nagem, R.A.P.
Structural and immunological characterization of a new nucleotidyltransferase-like antigen from Paracoccidioides brasiliensis.
Mol.Immunol., 112:151-162, 2019

PubMed Abstract: Pb27 antigen is an interesting alternative to immunological diagnosis of Paracoccidioidomycosis (PCM) and has demonstrated to be protective in experimental PCM. Its tertiary structure and possible function remained unknown till now. To study Pb27 at the atomic level, the recombinant protein was expressed in Escherichia coli BL21(DE3), purified, and its three-dimensional structure was solved by X-ray crystallography. Based on this structure, we performed a residue correlation analysis and in silico ligand search assays to address a possible biological function to Pb27. We identified Pb27 as a member of the extensive nucleotidyltransferase superfamily. The protein has an αβαβαβ topology with two domains (N- and C-terminal domains) and adopts a monomeric form as its biological unit in solution. Structural comparisons with similar members of the superfamily clearly indicate Pb27 C-terminal domain is singular and may play an important role in its biological function. Bioinformatics analysis suggested that Pb27 might bind to ATP and CTP. This suggestion is corroborated by the fact that a magnesium cation is coordinated by two aspartic acid residues present at the active site (between N- and C-terminal domains), as evidenced by X-ray diffraction data. Besides, NMR assays (H-N HSQC spectra) confirmed the binding of CTP to Pb27, demonstrating for the first time an interaction between a nucleotide and this protein. Moreover, we evaluated the reactivity of sera from patients with Paracoccidioides brasiliensis infection against the recombinant form of Pb27 and showed that it was recognized by sera from infected and treated patients. Predicted B and T cell epitopes were synthesized and further evaluated against sera of PCM patients, providing information of the most reactive peptides in Pb27 primary structure which interact with specific Pb27 antibodies.

PubMed: 31108423
DOI: 10.1016/j.molimm.2019.04.028

実験手法

X-RAY DIFFRACTION (1.86 Å)