与摩根·弗里曼一起穿越虫洞（2010）

Through The Wormhole With Morgan Freeman S05E06

Part 4 April 19, 2021, 3:03 p.m.

that binds to matching sequences of D.N.A.
如果样品中含有病毒
So then if that virus is present within that sample,
它就会被“鱼钩”勾住
it will be caught on the hook,
然后我卷起线就能找到它了
and I'll be able to reel it in, and I'll see it.
伊恩将数千个DNA诱饵
Ian can cast thousands of genetic lures
投放到样本中
into the sample.
每个诱饵都能与一种已知病毒发生特异性结合
Each one is tailored to attract a known virus.
病人的生物样本中
Biological samples from sick patients
充满了与诱饵无关的微生物
are oceans filled with microbes that ignore the lure,
只有特定的病毒
except for the virus that is a match
才会与诱饵DNA序列匹配
for the lure's D.N.A. sequence.
病毒准备好它的遗传密♥码♥
The virus lines up its genetic code --
A对应T，C对应G
A binds to T, C binds to G.
一旦病毒上钩了
Once it's hooked... Uh-oh.
诱饵的重量就会改变
The weight of the lure changes,
伊恩就能把病毒钓上来了
and Ian can reel in the virus.
如果这个方法起作用了
Now, if that method works, then we can get an answer
我们就能高效而又廉价地得到结果
very, very quickly, very inexpensively,
最多只需要4到6个小时就够了
probably in a matter of four to six hours at the outside.
但病毒的遗传密♥码♥
But viral and genetic code
会迅速进化
can evolve rapidly.
有时病毒的变化太大
Sometimes new viruses have changed so much
而不再和诱饵匹配
that they no longer stick to the lure.
这种情况下，伊恩会采用另一种手段
In that case, Ian switches to another technique --
把所有类型的DNA都用上
grab all the D.N.A. he can.
我有一个网
I have a net.
网上面有很多不同的DNA序列
This is essentially a D.N.A. sequence.
当我们不清楚样品中的病毒是什么时
When we don't know precisely what we're looking for,
就会用到一种高通量测序仪
we use a high-throughput sequencer
我们就能鉴定出
that allows us to characterize all of the genetic material
样本中的所有遗传物质
that'd be present within a sample.
我们会拉出所有的遗传物质
We pull everything in, and then we compare that
和已知基因的数据库进行比对
with a database of all known sequences.
这样我们就可以鉴定出样本中
That allows us to identify anything
哪些微生物会是我们的目标
which is potentially a microbial agent.
伊恩和他的团队
Ian and his team
分离并培养得到的病毒
then grow colonies of the isolated virus
尝试寻找
and attempt either to identify a drug
对抗该病毒的药物或开♥发♥针对它的疫苗
that can fight the infection or to develop a vaccine.
我和我的同事能够测试药物效力
We and our colleagues can begin testing drugs for efficacy,
药物能阻止病毒的繁殖
drugs that will be able to prevent this agent
从而控制病情
from reproducing itself.
然后接下来
And then, ultimately,
因为新药物通常比较昂贵
because drugs are frequently too expensive,
我们会尝试与开♥发♥疫苗的人
we try to collaborate with people
合作生产新疫苗
who know how to develop vaccines.
无论他们
No matter how quickly
对新病毒的鉴定速度有多快
they identify new viruses, however,
但要应用到治疗上仍会滞后
there will always be a lag time between detection and treatment,
而这段时间里病毒仍继续传播
a time when the virus can spread.
实验室的研究工作并不会有太大的滞后
The major time lag is not at the level of the laboratory.
进度主要是滞留在实际应用上
It's really in the field.
因为实际应用对于人们来说是全新的
It's recognizing the appearance of something as new.
还需要很多的工作
Then that has to percolate
人们才能够接受并使用新疗法
through the ether until it reaches people like us.
伊恩的团队能够
Ian's team could prevent
帮助数百万以上的人
millions if not billions of us
免受强传染性疾病的侵害
from succumbing to a highly infectious disease.
但如果病毒的进化方式
But if a virus evolves that is sufficiently different
与我们已知的病毒差异很大
from the viruses we know today,
伊恩的团队就无法把它“钓”出来了
Ian's team will not be able to fish it out.
在人类对抗病毒的战争中，我们需要新的策略
In humanity's war on viruses, we need a new strategy.
我们能够捕获病毒
We can hunt viruses down,
也可以接种疫苗防止传染
and we can try to vaccinate ourselves against them.
但一旦我们感染了病毒，只能任由它们的摆布
But once they infect us, we're at their mercy.
那么如果我们把病毒变成僵尸
What if we turn a virus into a zombie
为我们效力，转而去攻击僵尸病毒呢？
that works for us and make it kill a zombie virus?
上个世纪中
Modern medicine
现代医学战胜了许多疾病
has conquered many diseases in the past century.
然而，病毒还是很难对付
Viruses, however, remain elusive targets.
因为它们会劫持我们细胞中重要的遗传物质
Because they hijack the vital genetic machinery of our cells,
想要杀掉病毒变得非常棘手
killing them is tricky.
解决手段就需要一个这个东西
The solution may require a pair of these,
而且小到DNA的水平
shrunk down to the size of our D.N.A.
病毒算是聚会中的不速之客
Viruses are party crashers.
它们尽可能地混到健康细胞中
They do everything possible to blend in with healthy cells...
啊！
Aah!
病毒不断地
...All the while
感染其他参加聚会的客人
relentlessly infecting the invited guests.
对于重度感染的治疗
For severe infections,
目前最有效的方法非常粗暴
our best medical treatments today are crude.
将入侵者碎尸万段
They work by chopping up the harmful invaders...
聚会结束了
Party's over.
甚至附近所有的健康细胞
...And all the healthy cells
也不能幸免
in their vicinity.
但我们马上就会有一种可以避免伤害正常细胞
But a new treatment that only goes after the bad guys
新的靶向治疗方法
could be right around the corner.
加州大学圣芭芭拉分校的
As the director of the Center for Nanomedicine
纳米医学中心的主管杰米·玛撒
at U.C. Santa Barbara,
认为有一类化学物质很可能会是
Jamey Marth thinks it should be possible
良好的抗病毒药物
to make an antiviral drug
而它们普遍存在于我们的胃里
out of a class of chemicals that we all have in our stomachs.
我盘子里的这些食物
The food that I have on this plate right now
能让我健康生存
is what I need to keep me alive and mostly healthy.
为了吸收这些食物的营养
But for my body to use this material,
食物会被转化成其他形式
it has to convert it into different forms,
这个过程中需要叫做“酶”的天然加工机器
and it does that by using small natural machines called enzymes.
酶是微生物学中强有力的工具
Enzymes are the power tools of microbiology.
在胃里，酶将食物分解成可消化吸收的形式
In the stomach, they break apart our food into digestible forms.
杰米和他的同事正致力于
Jamey and his colleagues are working
研究一种叫做CRE的重组酶
with an enzyme called C.R.E. Recombinase.
这种酶的用途非常大
This enzyme has remarkable utility.
它能剪切所需的DNA片段
It can cut out any section of D.N.A.
还能将相邻的基因片段
And neatly staple back together
准确的连接起来
the two adjoining genetic pieces.
这种酶可以让我们
It's allowed us to do things
完成之前无法实现的工作
that we haven't been able to do before --
比如在特定的细胞中
to remove specific genes from specific cells
将特定的基因片段移除
at different times.
组成我们身体的每一个细胞中
Inside every cell in our body,
都有着大量的DNA
there is a forest of D.N.A.
病毒会携入外来基因
Viruses sneak foreign genes
插入原有的DNA中，并控制细胞功能
into this forest and hijack our cellular machinery.
有一种药物即基于杰米的CRE重组酶
A drug based on Jamey's C.R.E. Recombinase enzyme
能够清除病毒携入的DNA
could chop down viral infections at their root
从根本上阻止病毒感染
by weeding out their D.N.A.
这个酶需要识别被切除的基因片段两端
The enzyme needs to find a specific sequence
长度为34个碱基的DNA片段
of 34 genetic letters at either end of the cut.
而这34个碱基的序列可以订制
And that sequence can be customized.
所以一旦你知道了病毒的基因序列
So once you know the genetic sequence of a virus,
你就可以设计相应的CRE重组酶
you can program C.R.E. Recombinase
来识别病毒DNA两端并进行剪切
to latch onto the first and last parts of this D.N.A. code.
这个代表病毒的DNA
This represents viral D.N.A --
对细胞来说它是外来的DNA
D.N.A. that's foreign to the cell
病毒会把它整合到细胞的基因组中
and has integrated itself into the genome.
像CRE重组酶这样的酶
An enzyme like the C.R.E. Recombinase
能够从细胞的基因组中
is capable of removing this precisely
精确切除病毒DNA
from the cell's genome.
它切得非常精确
It does this with precision.
接着，这个酶就会
And then, what the enzyme will do
将正常的DNA链