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One of the leading researchers in the field of protein folding is David Baker of the University of Washington, in Seattle.
西雅圖華盛頓大學的David Baker是蛋白質折疊領域研究者的領軍人物之一。
For the past 20 years he and his colleagues have used increasingly sophisticated versions of a program they call Rosetta to generate various possible shapes for a given protein, and then work out which is most stable and thus most likely to be the real one.
在過去的20年中，他的團隊應利用越來越復雜的“Rosetta”程序，模擬出給定蛋白質的各種可能結構，然后研究對比哪一種結構最穩定并最接近于真正的蛋白質結構。
In 2015 they predicted the structures of representative members of 58 of the missing protein families.
2015年他們預測了58個未知蛋白質家族成員的代表結構。
Last month they followed that up by predicting 614 more.
就在1月份他們已預測出614多種蛋白質結構。
Even a small protein can fold up into tens of thousands of shapes that are more or less stable.
僅僅一個小的蛋白質也能折疊出數以千計的較為穩定的結構。
According to Dr Baker, a chain a mere 70 amino acids long—a tiddler in biological terms—has to be folded virtually inside a computer about 100,000 times in order to cover all the possibilities and thus find the optimum.
Baker博士表示，一條僅70個氨基酸長度的鏈，在生物界如同一個小孩兒，而想要找到所有的可能性并確定最佳結構需要在電腦中虛擬折疊近10萬次。
Since it takes a standard microprocessor ten minutes to do the computations needed for a single one of these virtual foldings, even for a protein this small, the project has, for more than a decade, relied on cadging processing power from thousands of privately owned PCs.
由于完成僅一個如此小的蛋白質的虛擬折疊便需標準微處理器計算耗時10分鐘，故這個項目在十多年來一直借助于上千臺個人電腦的處理能力。
Volunteers download a version of Dr Baker’s program, called rosetta@home, that runs in the background when a computer is otherwise idle.
志愿者可以下載rosetta@home，這是Baker博士的程序，當電腦閑置時可讓其在后臺運行。
This “citizen science” has helped a lot.
“全民科研”的作用很大。
But the real breakthrough, which led to those 672 novel structures, is a shortcut known as protein-contact prediction.
但真正的突破性進展是一個被稱為蛋白質-接觸預測的捷徑，使得科學家發現了672個新的蛋白質結構。
This relies on the observation that chain-folding patterns seen in nature bring certain pairs of amino acids close together predictably enough for the fact to be used in the virtual-folding process.
這得益于在鏈-折疊模式的自然狀態下，觀察到了特定的氨基酸對會被拉近在一起的現象，其可預測性足以用于虛擬折疊進程。
An amino acid has four arms, each connected to a central carbon atom.
一個氨基酸有4條支鏈，每支連接一個中心碳原子。
Two arms are the amine group and the acid group that give the molecule its name.
其中有2條支鏈是用于分子命名的胺基和酸根。
Protein chains form because amine groups and acid groups like to react together and link up.
蛋白質會互相連接是因為胺基遇到酸根，易反應并連接在一起。
The third is a single hydrogen atom.
第3條支鏈只有一個氫原子。
But the fourth can be any combination of atoms able to bond with the central carbon atom.
任何能和中心碳原子相連的任意原子組合，都能與第四條支鏈相連接。
It is this fourth arm, called the side chain, which gives each type of amino acid its individual characteristics.
這第4條支鏈叫做側鏈，賦予每種類型的氨基酸各自的性質。
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