Team:SCUT/HP/Magazine/iGEM People

Scientists Move Closer to Inventing Artificial Life 科学家真的做出了人造生命？

It is reported that an international team has inserted a man-made chromosome into brewer's yeast, producing a life form that thrives and successfully passes the designer genes on to its offspring.

据报道，一支由各国科学家组成的科研队伍近日将人造染色体成功导入啤酒酵母（我们常喝的青岛啤酒、珠江啤酒都是由靠这种重要的可食用菌发酵产生的哦!!!）内，创造出了可以独立健康成长并可将改造后的基因传给子孙后代的一种生命体形式。这一实验结果意味着人类在创造生命的路途上迈出了重要的第一步。下面我们就来具体看看这一全新生命体是如何被创造出来的。

Chromosomes are the packages for genes. In plants, animals, and fungi like yeast, they are contained within a cell nucleus, which simpler microbes like bacteria do not have. People have 23 pairs of chromosomes, and yeasts have 16. Best known for their role in baking bread and brewing beer, yeasts share about a third of their genes with people.

染色体是基因的集中体。在植物、动物和真菌等真核生物中，染色体存在于细胞核中；而在简单低等的原核生物如细菌，染色体和细胞核都是不存在的。相对于人类的23对染色体，用于酿酒和制作面包的酵母只有16对，并且酵母基因的三分之一都是人类基因中可以找到的。

（Pic 1 The budding yeast is just like roast photo with delicious sausage. 图为正在出芽的啤酒酵母,看起来像不像一个土豆盖着许多片烤香肠呢？ 嘿嘿，是不是又饿了^_^）

Tolerant of genetic tinkering, yeast played a role in a previous synthetic biology breakthrough, when scientists led by J. Craig Venter assembled the first artificial bacterial genome inside yeast cells in 2009. And man-made DNA strips cooked up inside yeasts, so-called yeast artificial chromosomes (YACs), have been used to make gene maps for decades. Yeast was one of the first organisms to have its entire genome sequenced, in 1996.

由于对基因改造有很好的耐受性，酵母在以往合成生物学的重大突破中都扮演了很重要的角色。2009年，以J.Craig Venter为首的科学家们在酵母细胞中组建了第一个人工细菌基因。另外，酵母中的某些DNA被人工敲除（使酵母中原有的一些可以表达的基因沉默不能表达，从而抑制相关生物功能），改造成为酵母人造染色体（YAC），多年来都被用作构建基因图谱。1996年，酵母成为第一个被全部测序的有机体。

The new study's "synIII" artificial chromosome implanted into brewer's yeast builds on this legacy. It crowns a seven-year "Build a Genome" project that involved more than 60 biologists in its assembly. 这项将“synIII”人造染色体植入啤酒酵母中的研究全部建立在上述基础上。它被称为“7年构建一个基因组”项目，共有60多位生物学家参与它的构建。

Essentially, the study researchers created a stripped-down, but still functional, third chromosome of brewer's yeast, which contains about 2.5 percent of the organism's total genes. 从本质上讲，这项研究的研究人员创造了一个更为精简但功能齐全的含有三分之一的原有染色体和2.5%基因总量的啤酒酵母。

“This is a major step towards being able to design completely novel organisms," says Todd Kuiken of the Woodrow Wilson International Center for Scholars in Washington, D.C. "The research team has created what some might call the first synthetic cell that was designed, built and reproduced without a host cell present," he says. “这是迈向设计出全新生物体的重要一步。“华盛顿特区Woodrow Wilson国际学者中心的Todd Kuiken说，“研究小组已经创造出第一个合成细胞，它能够不需要宿主细胞的存在而自主设计、构建和复制。”

Still awaiting scientists is the assembly of a complete artificial genome: man-made versions of all the chromosomes in a plant or animal. 仍有待科学家们完成的是一个完整的人造基因组的组装构建：所有动植物的人造基因组。

Ideally, synthetic biology will produce microbes with specific genetic codes embedded to cheaply churn out renewable fuels or medicines such as the antimalarial drug artemisinin.

科学家的理想是，合成生物学能够创造出植入特定基因的工程菌，这些工程菌可以廉价生产出可再生燃料和像抗疟药青蒿素这样的高成本药物。