Department of Biotechnology Engineering, Ben-Gurion University, Beer-Sheva, Israel.
Langmuir. 2010 Nov 2;26(21):16424-33. doi: 10.1021/la102166k.
A two-dimensional bio/synthetic hybrid system at the air-solution interface made of a polymerized diacetylene Langmuir film with nucleobase modified headgroups is presented. The polymerized film presents a crystalline array of nucleobases, capable of specific binding of complementary mononucleoside or oligonucleotide sequences. Mixed monolayers of the linear polyconjugated polydiacetylene (PDA) films derivatized with cytosine (10,12-pentacosadiyne-cytidyl, PDC) monomers and alcohol-terminated diacetylene lipid (10,12-pentacosadiynol, PDOH) at a 3:1 ratio (PDC 75%) were compressed and polymerized at the air-water interface with circular polarized light (CPL) or nonpolarized UV light. Here we report a grazing incidence X-ray diffraction (GIXD) investigation of PDC films polymerized to different chirality and hybridized with complementary ssDNA strands. We have demonstrated enantioselective interactions on synthetic structured interfaces produced by Langmuir surface compression followed by polymerization with circular polarized UV light (CPL). The left- and right-CPL polymerized light exhibit the same well-defined crystalline structure. The observed difference between left- and right-CPL polymerized PDC 75% Langmuir films compressed over the complementary mononucleotide guanosine or hybridized with fully complementary ssG(12)T(5) oligonucleotide in the subphase suggests that they are indeed enantiomeric structures, capable of enantioselective binding of their natural ligand, guanosine, solely as a result of surface induced asymmetry in "left" but not in "right" form. This observation may also be related to the intriguing question of chiral selection during the early period of "Origin of Life". We show that achiral compounds, as a result of irradiation with circular polarized light, can organize in chiral surface structures capable of amplification of biopolymer binding of particular handedness.
提出了一种由聚合二乙炔朗缪尔膜与碱基修饰头基组成的二维生物/合成杂化体系，该体系位于气-液界面。聚合膜呈现出碱基的结晶阵列，能够特异性结合互补的单核苷酸或寡核苷酸序列。用胞嘧啶（10,12-二十五碳二炔基胞苷，PDC）单体和醇端二乙炔脂质（10,12-二十五碳二炔醇，PDOH）修饰的线性聚共轭聚二乙炔（PDA）薄膜的混合单层以 3:1 的比例（PDC 为 75%）在空气-水界面上用圆偏振光（CPL）或非偏振紫外光压缩和聚合。在这里，我们报告了用圆偏振光（CPL）或非偏振紫外光聚合不同手性的 PDC 薄膜并与互补 ssDNA 链杂交的掠入射 X 射线衍射（GIXD）研究。我们已经证明了通过朗缪尔表面压缩然后用圆偏振紫外光（CPL）聚合产生的合成结构化界面上的对映选择性相互作用。左、右旋 CPL 聚合光表现出相同的明确定晶结构。在亚相中互补单核苷酸鸟嘌呤压缩或与完全互补 ssG（12）T（5）寡核苷酸杂交的 PDC 75%朗缪尔膜的左旋和右旋 CPL 聚合光之间观察到的差异表明，它们确实是对映异构体结构，能够仅作为“左”而不是“右”形式的表面诱导不对称的结果，对其天然配体鸟嘌呤进行对映选择性结合。这种观察结果也可能与“生命起源”早期的手性选择问题有关。我们表明，非手性化合物由于圆偏振光的照射，可以在能够放大特定手性的生物聚合物结合的手性表面结构中进行组织。
