4IIL

Crystal Structure of RfuA (TP0298) of T. pallidum Bound to Riboflavin

4IIL の概要

• エントリーDOI: 10.2210/pdb4iil/pdb
• 分子名称: Membrane lipoprotein TpN38(b), RIBOFLAVIN, SODIUM ION, ... (6 entities in total)
• 機能のキーワード: periplasmic-binding protein, riboflavin transport, membrane protein
• 由来する生物種: Treponema pallidum subsp. pallidum
• 細胞内の位置: Cell membrane ; Lipid-anchor : Q56328
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 39061.48

構造登録者

Brautigam, C.A.,Deka, R.K.,Norgard, M.V. (登録日: 2012-12-20, 公開日: 2013-02-27, 最終更新日: 2024-02-28)

主引用文献

Deka, R.K.,Brautigam, C.A.,Biddy, B.A.,Liu, W.Z.,Norgard, M.V.
Evidence for an ABC-type riboflavin transporter system in pathogenic spirochetes.
MBio, 4:e00615-e00612, 2013

PubMed Abstract: Bacterial transporter proteins are involved in the translocation of many essential nutrients and metabolites. However, many of these key bacterial transport systems remain to be identified, including those involved in the transport of riboflavin (vitamin B(2)). Pathogenic spirochetes lack riboflavin biosynthetic pathways, implying reliance on obtaining riboflavin from their hosts. Using structural and functional characterizations of possible ligand-binding components, we have identified an ABC-type riboflavin transport system within pathogenic spirochetes. The putative lipoprotein ligand-binding components of these systems from three different spirochetes were cloned, hyperexpressed in Escherichia coli, and purified to homogeneity. Solutions of all three of the purified recombinant proteins were bright yellow. UV-visible spectra demonstrated that these proteins were likely flavoproteins; electrospray ionization mass spectrometry and thin-layer chromatography confirmed that they contained riboflavin. A 1.3-Å crystal structure of the protein (TP0298) encoded by Treponema pallidum, the syphilis spirochete, demonstrated that the protein's fold is similar to the ligand-binding components of ABC-type transporters. The structure also revealed other salient details of the riboflavin binding site. Comparative bioinformatics analyses of spirochetal genomes, coupled with experimental validation, facilitated the discovery of this new ABC-type riboflavin transport system(s). We denote the ligand-binding component as riboflavin uptake transporter A (RfuA). Taken together, it appears that pathogenic spirochetes have evolved an ABC-type transport system (RfuABCD) for survival in their host environments, particularly that of the human host.

PubMed: 23404400
DOI: 10.1128/mBio.00615-12

実験手法

X-RAY DIFFRACTION (1.3 Å)