Jezowska I, Wolak A, Gruszecki W I, Strzałka K
Institute of Physics, Jagiellonian University, Kraków, Poland.
Biochim Biophys Acta. 1994 Aug 24;1194(1):143-8. doi: 10.1016/0005-2736(94)90213-5.
Spin label EPR studies (Strzałka and Gruszecki (1994) Biochim. Biophys. Acta 1194, 138-142) revealed that beta-carotene affects structural and dynamic properties of model dipalmitoylphosphatidylcholine (DPPC) membranes (multilamellar liposomes) more than polar carotenoid lutein. NMR measurements presented in this paper demonstrate that beta-carotene exerts different effect on various groups of the DPPC molecule. It was found that beta-carotene: (1) increases motional freedom of lipid headgroups as revealed by means of 31P-NMR; (2) increases motional freedom of alkyl chains forming the hydrophobic core of the membrane greater than that of a choline moiety as revealed by means of 13C-NMR. In all cases the effect of beta-carotene with respect to the dynamics of DPPC molecules is found to be more pronounced below the main phase transition temperature than in the membrane's fluid state. The influence of beta-carotene on the molecular dynamics of DPPC molecules is discussed in terms of localization and orientation of this pigment within lipid bilayer.
自旋标记电子顺磁共振研究（Strzałka和Gruszecki（1994年），《生物化学与生物物理学报》1194卷，第138 - 142页）表明，β-胡萝卜素对模型二棕榈酰磷脂酰胆碱（DPPC）膜（多层脂质体）的结构和动力学性质的影响比极性类胡萝卜素叶黄素更大。本文所展示的核磁共振测量结果表明，β-胡萝卜素对DPPC分子的不同基团有不同影响。研究发现，β-胡萝卜素：（1）如通过31P - NMR所示，增加了脂质头部基团的运动自由度；（2）如通过13C - NMR所示，增加了构成膜疏水核心的烷基链的运动自由度，且对烷基链运动自由度的增加作用大于胆碱部分。在所有情况下，发现β-胡萝卜素对DPPC分子动力学的影响在主相变温度以下比在膜的流体状态下更为明显。从该色素在脂质双层中的定位和取向角度讨论了β-胡萝卜素对DPPC分子动力学的影响。
