译言网 | 细菌实验中天然基因的代用品：人造基因

细菌实验中天然基因的代用品：人造基因

译者： 心中有爱，鲜花盛开

发表时间：2011-01-13浏览量：1581评论数：0挑错数：0

基因可以转，可以合成，真不知道，这对我们人类而言，福焉？祸焉？这也许只能让时间来回答。

A handful of bacterial genes crucial to survival were successfully replaced by artificial ones in a new synthetic-biology experiment.

在一项新的合成生物学实验中，为数不多的几个与生存性命攸关的细菌基因已经成功的为人造基因所替代。

还不十分清楚人造基因如何拯救濒临死亡的E.螺旋形细菌的，有DNA的几个重要的排序彻底击败了其基因组。但是科学家们考虑用崭新的基因方法生产合成蛋白质，用以替代消失的自然物种。

“To enable life you need genes and proteins, which are information and machines,” said molecular biologist Michael Hecht of Princeton University, co-author of the study published online in PLoS ONE. “These evolved over a very long period of time, but we wanted to ask, ‘Are they really special, or can we make stuff like them from scratch?’ It seems we can.”

普里斯顿大学的分子生物学家迈克尔赫奇特先生，在线公共科学图书馆文献的共同作者，指出：“基因和蛋白质使生命成为可能，基因和蛋白质是建造生命的材料和机器。基因和蛋白质在一个相当漫长的时间里不断的进化，但是我们也需要问这样的问题：‘它们真的很独特吗？或者我们能够采用拭擦的方式获取基本材料吗？’似乎我们可以做到。”

合成生物学家最基本的目标之一，是创造可定制的有机物，从而能够生产出食物，燃料，或是药品，直至清除环境有害物质，或者仅仅就像一台计算机一样工作。

绝大多数的合成生物学实验，包括克雷格文特尔研究中心最新创造出来合成生命组织，都以自然界存在的基因为基础。然而，在新的实验中，赫奇特先生和他的研究团队一起改变一百五十万万个来源于拭擦取得的基因的半随机程序库。

Genes contain instructions for building proteins, which are made of units called amino acids. There are 20 different amino acids a protein can be made of, and some sequencesmake a protein fold into three dimensions.

基因中包含有形成蛋白质的指令，这个指令是由称作氨基酸的单元组成的。有２０种不同的可以形成蛋白质的氨基酸，一些排序的氨基酸形成的蛋白质，会是三维的。

Each gene in Hecht’s synthetic library calls for proteins made of 102 amino acids. Yet, instead of randomly filling each spot, the genes included sequences prompting them fold into four-helix structures (right).

赫奇特先生的人造基因库中的每一种基因需要的蛋白质是由１０２种氨基酸制成的。然而，代之以随机的填满每一个斑点，包含了一定排序的基因促使其成为四螺旋结构。（右旋）

“Folding in three dimensions [is required for functionality] when it comes to proteins, so the library isn’t completely randomized,” Hecht said. “You might think of it as a targeted shotgun of randomness instead of a bomb of it.”

赫奇特先生还告诉我们：“当其形成蛋白质的时候，基因在三维空间上折叠（为实际所需要），所以基因库不是完完全全随机的。也许你可以这样看待这个问题，基因是随机有目标的射击，而不是基因轰炸。”

Twenty-seven strains of E. coli, each missing one gene critical for survival, individually mingled with the synthetic-gene library. Four strains of bacteria incorporated a synthetic gene into their DNA and grew on Petri dishes that contained only the bare nutrients for survival. Without the new genes, the four strains didn’t grow at all.

E.螺旋的二十七种菌株，每一种的消失都对生存至关重要的基因，单个与人造基因库缠绕在一起。四种细菌的菌株与人造基因结合在一起，形成了它们的DNA，这些菌株是从只有用于生存的养分的Petri盘上培养出来的。如果没有这种新基因，这四种菌株就完全不能生长了。

Taking the rescue of doomed microbes further, Hecht’s team made a strain of E. coli missing all four genes from the previous experiments. When the synthetic replacement genes from the library were added, the microbe was rescued.

为了更进一步的解救难逃一死的细菌，从早些时候的实验中，赫奇特的研究团队制作了一种消失的四种基因E.螺旋的菌株。当添加了来自于基因库的人造替代基因，细菌就获救了。

“I think this is a very interesting start to some more research,” said biotechnologist Andrew Ellington of the University of Texas at Austin, who was not involved with the experiments. “I’d like to see more proof that these proteins are doing what [Hecht] says they’re doing…. There may be some weird things going on.”

没有参与该项实验的得克萨斯州奥斯丁大学的生物工艺学家安德鲁爱林顿教授这样说：“我想，对于更进一步的研究而言，这是一个非常有趣的开始。我更希望看到更多的证据，能够证明赫奇特所说的他们‘做’的蛋白质的存在......会有一些神秘的事情继续的。”

Hecht said “it would be nice” to untangle the biochemistry of his genetic rescues, adding that the synthetic genes weren’t exactly optimum replacements for nature’s versions that were chiseled over billions of years of evolution. But he said that’s not the biggest takeaway from the experiment.

赫奇特指出解开他的基因拯救的生物化学的“情况会越来越好的”，并且还进一步说明，经过超过亿年进化的自然界基因轮廓清晰，对于这种基因而言，人造基因确实不是最优先的替代品。但是他还指出，基因拯救不是来自实验的最优的快餐食品。

“We know which specific genetic sequences rescue the strains, even if we don’t yet know how they work,” Hecht said.

赫奇特说：“虽然我们不知道这些基因是如何起作用的，但是我们的确明了是哪种特定基因排列顺序拯救了菌株。”

In addition to following up on the biochemistry of the genes that revived the bacteria, Hecht’s laboratory plans to engineer more-complex libraries and knock out even-more-crucial genes.

并且为了继续复活细菌的基因生物化学的研究，赫奇特的实验室计划改变更复杂的基因库，而且击破一些更关键的基因。

“‘How far can you go with this?’ is what we want to know. Could you knock out 100 genes and rescue all of them? Eventually a whole genome?” Hecht said.

赫奇特也感到很困惑：“‘在这项研究上我们能走多远？”正是我们想知道的，你能击破１００种基因，并拯救所有这些基因吗？最终拯救整个基因组吗？