日本东京大学研究人员用简单的有机化合物合成了能够自我增殖的人造细胞。这种增殖方式类似大肠杆菌的细胞有望成为探索生物起源的线索。
取得这项成果的是东京大学名誉教授菅原正等组成的团队。研究人员先利用类似界面活性剂的分子、催化剂以及水制成双层膜。然后把混有从大肠杆菌提取的DNA（脱氧核糖核酸）和DNA合成酶的水注入双层膜，让膜包裹着含DNA的水，形成外观像细胞的直径1至10微米的球体。
之后，让球体内液体的温度升高至95摄氏度再下降到65摄氏度。在不断重复这种温度变化的过程中，加上酶的效用，DNA成功复制，经过20次反复，DNA增加至100多万倍。
DNA增加后，再添加制作膜的有机化合物，部分DNA就附着到双层膜内壁，人造细胞开始膨胀，约4分钟后如同天然细胞分裂一样从中间断裂，形成新细胞。在实验中一个人造细胞能分裂出8到10个细胞。
据介绍，虽然在这次研究中使用来自于大肠杆菌的DNA，不过即使使用人工合成的DNA，人造细胞也能实现同样的增殖。
相关研究论文发表在5日的英国《自然—化学》杂志网络版上。(生物谷 Bioon.com）
doi:10.1038/nchem.1127
PMC:
PMID:
Self-reproduction of supramolecular giant vesicles combined with the amplification of encapsulated DNA
Kensuke Kurihara; Mieko Tamura; Koh-ichiroh Shohda; Taro Toyota; Kentaro Suzuki; Tadashi Sugawara
The construction of a protocell from a materials point of view is important in understanding the origin of life. Both self-reproduction of a compartment and self-replication of an informational substance have been studied extensively, but these processes have typically been carried out independently, rather than linked to one another. Here, we demonstrate the amplification of DNA (encapsulated guest) within a self-reproducible cationic giant vesicle (host). With the addition of a vesicular membrane precursor, we observe the growth and spontaneous division of the giant vesicles, accompanied by distribution of the DNA to the daughter giant vesicles. In particular, amplification of the DNA accelerated the division of the giant vesicles. This means that self-replication of an informational substance has been linked to self-reproduction of a compartment through the interplay between polyanionic DNA and the cationic vesicular membrane. Our self-reproducing giant vesicle system therefore represents a step forward in the construction of an advanced model protocell.
