Infrared multiphoton dissociation of the siderophore enterobactin and its Fe(III) complex. Influence of Fe(III) binding on dissociation kinetics and relative energetics
Infrared multiphoton dissociation of the siderophore enterobactin and its Fe(III) complex. Influence of Fe(III) binding on dissociation kinetics and relative energetics
复制标题
铁载体肠杆菌素及其 Fe(III) 复合物的红外多光子解离。
DOI：
10.1016/j.jasms.2006.11.011
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发表时间：
2007
影响因子：
3.2
通讯作者：
D. Volmer
中科院分区：
文献类型：
--
作者：
A. Leslie;Rambod Daneshfar;D. Volmer
利用红外多光子解离（IRMPD）研究了铁载体肠杆菌素及其与铁（III）配合物的解离途径。在实验条件下（pH = 3.5），两种化合物的电喷雾光谱均呈现出单电荷阴离子。利用傅里叶变换离子回旋共振质谱（FT-ICR MS）对分离产物的组成进行了精确的质量测量。两个物种的主要解离通道被确定为从前体分子中失去一个丝氨酸基团。为了进一步研究Fe（III）结合对分子内相互作用的影响，采用聚焦辐射气体多光子能量转移（FRAGMENT）方法测定了该丝氨酸基团损失的解离动力学和相对能量学。从动力学数据来看，在所研究的激光强度范围内，肠obactin的反应性是其Fe（III）配合物的7倍。然而，相对活化能表现出相似的值，约7 kcal·mol−1。这些结果表明，在pH = 3.5时，Fe（III）只与三个丝氨酸基团中的两个相互作用。从目前的工作结果被认为是有价值的表征新的铁载体及其相关的代谢物和合成类似物。
The dissociation pathways of the siderophore enterobactin and its complex with Fe(III) were examined using infrared multiphoton dissociation (IRMPD). Under experimental conditions (pH = 3.5), both compounds’ electrospray spectra exhibited exclusively singly-charged anions. The compositions of the dissociation products were characterized by accurate mass measurements using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). The primary dissociation channel for both species was determined to be the loss of one serine group from the precursor molecules. To further investigate the influence of Fe(III) binding on the intramolecular interactions, dissociation kinetics and relative energetics for the loss of this serine group were determined using the focused radiation for gaseous multiphoton energy-transfer (FRAGMENT) method. From the kinetic data, it was found that enterobactin was ∼seven times more reactive than its Fe(III) complex over the range of laser intensities investigated. The relative activation energies, however, exhibited similar values, ∼7 kcal · mol−1. These results suggest that at pH = 3.5, Fe(III) interacts with only two of the three serine groups. The results from the present work are believed to be valuable for the characterization of novel siderophores as well as their associated metabolites and synthetic analogues.
影响因子：
16
作者：
Goetz, DH;Holmes, MA;Strong, RK
通讯作者：
Strong, RK
大肠杆菌铁肠杆菌素酯酶的过表达和纯化。
DOI：
--
发表时间：
1992
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Brickman,TJ;McIntosh,MA
通讯作者：
McIntosh,MA
影响因子：
7.4
作者：
LITTLE, DP;SPEIR, JP;MCLAFFERTY, FW
通讯作者：
MCLAFFERTY, FW