Ferric Stability Constants of Representative Marine Siderophores: Marinobactins, Aquachelins, and Petrobactin
作者:Guangping Zhang、Shady A. Amin、Frithjof C. Küpper、Pamela D. Holt、Carl J. Carrano、Alison Butler
DOI:10.1021/ic901739m
日期:2009.12.7
hydroxamate groups are coordinated to Ga(III); however, the lack of CISs for the carbons of the β-hydroxyamide group suggests this moiety is not coordinated in the Ga(III) complex. Differences in the IR spectrum of Ga(III)-marinobactin-C and Fe(III)-marinobactin-C in the 1600−1700 cm−1 region also corroborates Fe(III) is coordinated to the β-hydroxyamide moiety, whereas Ga(III) is not coordinated.
据报道,铁 (III) 与海洋两亲性 marinobactin 和 aquachelin 铁载体以及 petrobactin(一种不寻常的 3,4-二羟基苯甲酰铁载体)的配位。对apo铁载体进行电位滴定以确定配体pKa值,以及通过添加1当量的Fe(III)形成的复合物。Fe(III)-marinobactin-E 和 Fe( III )-aquachelin-C 的log K ML值分别为 31.80 和 31.4,与每个配合物中类似的配位环境一致,而 Fe(III) - Petrobactin估计约为43。通过1 H NMR滴定测定β-羟基天冬氨酰羟基的p Ka为10.8 。13 C NMR 和红外光谱用于研究 Ga(III) 与 marinobactins 的配位。Ga(III)-marinobactin-C 与 apo-marinobactin-C 相比,13 C NMR 谱中的配位诱导位移