Laboratory of Biointerphases and Biomimetic Systems, Applied Biophysics and Food Research Center (Centro de Investigaciones en Biofísica Aplicada y Alimentos, CIBAAL, National University of Santiago del Estero and CONICET), RN 9 - Km 1125, 4206 Santiago del Estero, Argentina.
Laboratory of Biointerphases and Biomimetic Systems, Applied Biophysics and Food Research Center (Centro de Investigaciones en Biofísica Aplicada y Alimentos, CIBAAL, National University of Santiago del Estero and CONICET), RN 9 - Km 1125, 4206 Santiago del Estero, Argentina.
Biochim Biophys Acta Biomembr. 2024 Jun;1866(5):184328. doi: 10.1016/j.bbamem.2024.184328. Epub 2024 Apr 28.
The interaction of L-Phe with the membrane components, i.e., lipids and proteins, has been discussed in the current literature due to the interest to understand the effect of single amino acids in relation to the formation of amyloid aggregates. In the present work, it is shown that L-Phe interacts with 9:1 DMPC (1,2-dimyristoyl-sn-glycero-3 phosphocholine)/DPPC (1,2-dipalmitoyl-sn-glycero-3 phosphocholine) mixtures but not in the 1:9 one. An important observation is that the interaction disappears when DPPC is replaced by diether PC (2-di-O-hexadecyl-sn-glycero-3-phosphocholine) a lipid lacking carbonyl groups (CO). This denotes that CO groups may interact specifically with L-Phe in accordance with the appearance of a new peak observed by Infrared spectroscopy (FTIR-ATR). The interaction of L-Phe affects the compressibility pattern of the 9:1 DMPC/DPPC mixture which is congruent with the changes observed by Raman spectra. The specific interaction of L-Phe with CO, propagates to phosphate and choline groups in this particular mixture as analyzed by FTIR-ATR spectroscopy and is absent when DMPC is dopped with diether PC.
由于人们对了解单个氨基酸与淀粉样纤维形成之间的关系很感兴趣，因此目前的文献中已经讨论了 L-苯丙氨酸与膜成分（即脂质和蛋白质）的相互作用。在本工作中，已经表明 L-苯丙氨酸可与 9:1 DMPC（1,2-二肉豆蔻酰基-sn-甘油-3-磷酸胆碱）/DPPC（1,2-二月桂酰基-sn-甘油-3-磷酸胆碱）混合物相互作用，但不能与 1:9 的混合物相互作用。一个重要的观察结果是，当 DPPC 被不含羰基（CO）的二醚 PC（2-二-O-十六烷基-sn-甘油-3-磷酸胆碱）取代时，这种相互作用就会消失。这表示 CO 基团可能会与 L-苯丙氨酸特异性相互作用，这与红外光谱（FTIR-ATR）所观察到的新峰的出现一致。L-苯丙氨酸的相互作用会影响 9:1 DMPC/DPPC 混合物的可压缩性模式，这与拉曼光谱所观察到的变化一致。通过 FTIR-ATR 光谱分析，已经表明 L-苯丙氨酸与 CO 的特异性相互作用会在该特定混合物中传播到磷酸酯和胆碱基团，而当 DMPC 中加入二醚 PC 时，这种相互作用就不存在。
