Streptococcus pneumoniae is a Gram-positive human pathogen that causes millions of infections worldwide with an increasing occurrence of antibiotic resistance. Iron acquisition is essential for its survival and virulence, especially under host-imposed nutritional immunity. S. pneumoniae expresses several ATP-binding cassette (ABC) transporters to facilitate acquisition under iron limitation, including PitABCD, PiaABCD, and PiuBCDA. The substrate specificity of PiuBCDA is not fully established. Herein, we report the backbone ¹H, ¹³C and ¹⁵N resonance assignments of the 31 kDa soluble, extracellular domain of the substrate binding protein PiuA in the apo form and in complex with Ga(III) and the catechol siderophore-mimic 4-LICAM. These studies provide valuable information for further functional studies of interactions with other proteins, metals, and small molecules.

中文翻译：

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来自肺炎链球菌的 ABC 转运蛋白溶质结合蛋白 PiuA 的 apo 和全息形式的 1H、13C、15N 骨架共振分配。

肺炎链球菌是一种革兰氏阳性人类病原体，在全球范围内引起数以百万计的感染，抗生素耐药性的发生率也在增加。铁的获取对其生存和毒力至关重要，尤其是在宿主强加的营养免疫条件下。肺炎链球菌表达几种 ATP 结合盒 (ABC) 转运蛋白以促进铁限制下的获取，包括 PitABCD、PiaABCD 和 PiuBCDA。PiuBCDA 的底物特异性尚未完全确定。在此，我们报告了主链¹ H、¹³ C 和¹⁵apo 形式的底物结合蛋白 PiuA 的 31 kDa 可溶性胞外域的 N 共振分配，并与 Ga(III) 和儿茶酚铁载体模拟 4-LICAM 复合。这些研究为与其他蛋白质、金属和小分子相互作用的进一步功能研究提供了有价值的信息。