7LM6

Crystal structure of the Zn(II)-bound AdcAII H205L mutant variant of Streptococcus pneumoniae

7LM6 の概要

• エントリーDOI: 10.2210/pdb7lm6/pdb
• 分子名称: Adhesion protein, ZINC ION (2 entities in total)
• 機能のキーワード: sbp, atp-binding cassette transporter, zn acquisition, metal binding protein
• 由来する生物種: Streptococcus pseudopneumoniae 5247
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 33477.60

構造登録者

Luo, Z.,Zupan, M.,McDevitt, C.A.,Kobe, B. (登録日: 2021-02-05, 公開日: 2021-09-29, 最終更新日: 2023-10-18)

主引用文献

Zupan, M.L.,Luo, Z.,Ganio, K.,Pederick, V.G.,Neville, S.L.,Deplazes, E.,Kobe, B.,McDevitt, C.A.
Conformation of the Solute-Binding Protein AdcAII Influences Zinc Uptake in Streptococcus pneumoniae .
Front Cell Infect Microbiol, 11:729981-729981, 2021

PubMed Abstract: scavenges essential zinc ions from the host during colonization and infection. This is achieved by the ATP-binding cassette transporter, AdcCB, and two solute-binding proteins (SBPs), AdcA and AdcAII. It has been established that AdcAII serves a greater role during initial infection, but the molecular details of how the protein selectively acquires Zn(II) remain poorly understood. This can be attributed to the refractory nature of metal-free AdcAII to high-resolution structural determination techniques. Here, we overcome this issue by separately mutating the Zn(II)-coordinating residues and performing a combination of structural and biochemical analyses on the variant proteins. Structural analyses of Zn(II)-bound AdcAII variants revealed that specific regions within the protein underwent conformational changes direct coupling to each of the metal-binding residues. Quantitative metal-binding assays combined with affinity determination and phenotypic growth assays revealed that each of the four Zn(II)-coordinating residues contributes to metal binding by AdcAII. Intriguingly, the phenotypic growth impact of the mutant alleles was, in general, independent of affinity, suggesting that the Zn(II)-bound conformation of the SBP is crucial for efficacious metal uptake. Collectively, these data highlight the intimate coupling of ligand affinity with protein conformational change in ligand-receptor proteins and provide a putative mechanism for AdcAII. These findings provide further mechanistic insight into the structural and functional diversity of SBPs that is broadly applicable to other prokaryotes.

PubMed: 34490149
DOI: 10.3389/fcimb.2021.729981

実験手法

X-RAY DIFFRACTION (3.367 Å)