ADM-201 dump PMP dumps pdf SSCP exam materials CBAP exam sample questions

给自己注射致命细菌 – 译学馆
未登陆,请登陆后再发表信息
最新评论 (0)
播放视频

给自己注射致命细菌

Injecting Yourself with Killer Bacteria

无论大家谈论的是人还是动物 都有可能被他们的外表欺骗
Whether they’re talking about people or animals, looks can be deceiving.
看上去是最无辜的小生物都有可能给人致命一击!
The most innocent-looking critters can pack a huge punch.
以这条小鱼为例
Take this tiny fish.
看上去十分可爱 对吗?
Pretty cute, right?
或者如果你是躲在暗处的狩猎者 这看上去会是美味的一餐
Or maybe it’d look like a tasty snack if you were a predator in a reef.
至少在它还没有露出在下颚的那对能注射毒性很强的尖利毒牙时
At least, until it reveals a pair of sharp fangs in its lower jaw, which can inject a potent venom.
这就是为什么它被叫做劳旦横口鳚
That’s why it’s called a fangblenny.
但是劳旦横口鳚的毒液并不强
But there’s a twist to the fangblenny’s toxic bite.
虽然他能使捕食者晕头转向 但是不会像黄貂鱼脊柱毒液那样使人感到灼痛
It seriously messes up predators but, unlike the searing pain from something like a stingray
或许它的毒液毒性不强
spine, the venom probably doesn’t hurt much at all.
实际上 一支国际生物家团队于这周在《当代生物学》上发表称
In fact, an international team of biologists reported this week in the journal Current
在毒液中的一种化学物质更像是止痛药
Biology that one of the chemicals in the venom is more like a painkiller.
所以或许有一天我们会将它用到药物中
So we might even be able to someday use it in medicine!
这些都是第一批科学家研究劳旦横口鳚毒液
These were the first scientists to analyze fangblenny venom.
他们发现了三种类型的毒素蛋白质 以前都没有在鱼类中
And they found three types of proteins that act as toxins, none of which had ever been
发现过
found in fish before.
其中就是一种特别的酶 与蜜蜂和蛇毒液中的一种酶很像
One was a special type of enzyme similar to those in bee and snake venom, which can do
它可以通过毁坏细胞膜造成很大伤害
a lot of damage by ripping apart cell membranes.
并且在锥形蜗牛中还发现了一种神经肽 它可以作为一种
Plus, there was a neuropeptide that’s also found in cone snails, which could be acting
神经递质
as a neurotransmitter.
第三种肽能附着与类鸦片受体上
And the third kind of peptide could bind to opioid receptors, and block pain, among other
阻止疼痛
effects.
有些蝎子会用相似的蛋白质
Some scorpions use similar proteins.
基本上 这种小小的横口鳚已经进化到将蛇 蜗牛和蝎子的毒液
Basically, the itty-bitty fangblenny evolved a venom that’s snake, snail, and scorpion
融为一体了
venom – all rolled into one.
至于毒液是如何起作用的 小白鼠的实验显示它主要的作用就是
As for how this venom works, tests on rats showed that its main effect is to dramatically
大幅降低血压 或许是因为两个肽键
lower blood pressure, probably because of the two peptides.
科学家认为即使不疼 也因如阿片类药物的化合物作用
The scientists think this blood pressure drop could make any predators uncoordinated, or
血压的降低会使任何捕食者生理不协调或者开始剧烈抖动
even start violently shaking… even if it’s not painful because of the opioid-like compound.
这也足够让横口鳚在不受任何伤地情况下溜走
That’s enough to let a fangblenny slip away without a scratch.
这种计谋如此有效以至于让很多无害的鱼也逐渐进化效仿
It’s a good enough strategy that lots of harmless fish have evolved to mimic venomous
从他们的颜色到游泳姿势
fangblennies, from their colors to their swimming styles.
或许人类也能从模仿横口鳚中获得好处
And humans might be able to benefit by copying the fangblenny, too.
研究毒液的科学家们常留心能用于制药的新分子
Scientists who study venoms are always on the look-out for new molecules that could
研究者们说这种不同寻常的毒液作为一种新型止疼药
be useful in medicine, and the researchers say this unique venom might be worth studying
或许值得研究
as a new type of painkiller.
如果从鱼类毒液中研发出新药听上去很奇怪那么有些科学家正考虑
If it sounds weird to look in fish venom for new drugs, some scientists are considering
用细菌做抗生素 那就更奇怪了
an even stranger prospect: using bacteria as antibiotics.
抗生素 当然 是用来杀死细菌的
Antibiotics, of course, are supposed to kill bacteria.
所以这种把更多细菌注射到你藏有细菌的体内的想法看起来有些
So the idea of injecting more bacteria into your bacteria-ridden body seems… kind of
疯狂
bananas.
但这种被叫做食菌蛭弧菌或者BV的细菌或许有用
But this bacterium – called Bdellovibrio bacteriovorus, or BV for short – could help.
在这周的《生物》杂志中 科学家称学习到了更多关于
In a paper published this week in Biophysical Journal, scientists learned more about how
这些暗杀者是如何捕食的
these assassins hunt.
这些细菌或许能提供一种新方式去治疗能抵抗
These bacteria might offer a new way to treat infections that are resistant to multiple
多重药物治疗或者打破生物膜的 多样集合 附着于表面的细菌的感染
drugs, or bust apart biofilms, the slimey collections of microbes that coat surfaces,
如用于医疗器材上
like on medical equipment.
BV如病毒一样能杀死其他细菌
BV kills other bacteria kind of like a virus does.
它挤进细菌细胞里 复制重生 然后所有的克隆宝宝们都闯出来
It squeezes inside a bacterial cell, replicates, and then all those clone babies burst out,
杀死寄主
killing the host.
因为它与抗生素作用方式不一样 通常它攻击特定目标在细菌细胞周围或里面
Because it works differently from antibiotics, which usually target specific bits around
BV甚至在其他药物都失败后还能杀死细菌
or inside bacterial cells, BV can kill bacteria even after many drugs have failed.
细菌似乎不会进化去抵抗这种攻击来保卫自己
Bacteria don’t seem to evolve ways to defend themselves against this kind of attack.
你的细胞很安全 因为BV只能在革兰氏阴性细菌中生长 比如
And your cells are safe, because BV can only grow inside gram-negative bacteria, like E.
大肠埃氏菌 沙门氏菌 都有种特定的细胞壁包围着它们
coli or Salmonella, which have a specific kind of cell wall surrounding them.
但是当我们知晓BV的寿命周期而且甚至有它的基因序列
But while we know some things about BV’s life cycle, and even have its genome sequenced,
BV是如何找到猎物的还是个迷
how BV finds its prey has been a mystery.
BV是一个活跃的捕食者吗?是通过感觉化学信号来追踪它的受害者吗?
Is BV an active hunter, tracking its victims by sensing chemical signals?
或者只是无意碰到的?
Or is it just bumping into them by chance?
知道细菌用的是哪种战术 对于如何把它作为治疗手段使用 是非常有帮助的
Knowing which tactic the bacteria use could be really helpful in figuring out how to use
不论是对于医院还是人体
them as a treatment, whether in hospitals or human bodies.
好吧 在这周的研究中 印第安纳州立大学的科学家们发现
Well, in the study from this week, scientists at Indiana University found that BV movement
BV的运动是无序的 但他有个小技巧去捕食猎物
is random, but it has a trick for upping its chances of running into its victims.
研究者用显微镜去观察在液体中的BV
The researchers used microscopes to watch BV, along with some E. coli prey, swimming
和一些大肠埃希氏菌
in some liquid.
游动是关键
That swimming is the key.
细菌用鞭毛推动自己在水中快速前进
The bacterium has a flagellum that propels it through water super quickly.
它可以在一秒内覆盖100倍的身体长度
It can cover a distance 100 times its body length in one second!
所有的尾部抖动都会产生大量的旋转波 这使得BV在圆圈中游泳
All that tail-whipping makes a lot of swirling waves, which makes BV swim in circles and
在表面上 或者在这种情况下会有其他的障碍
zero in on surfaces, or other obstacles – in this case, microbeads the researchers added.
那些表面也是大多数大肠埃希氏菌的地域
And those surfaces were also the regions with the most E. coli.
大肠埃希氏菌更大 更慢 但也在同样的地方被捕食
E. coli is bigger and slower, but also gets trapped in the same places because of the
因为他游泳的方式
way it swims.
所以 即使BV不用化学信号也知道猎物在做什么
So, even though BV doesn’t use any chemical or electrical signals to know what it’s
它仍然最终会在其他细菌可能出现的地方
doing, it still ends up where other bacteria are likely to be.
可能科学家能使细菌变得更敏感
It’s possible scientists could engineer the bacterium to be even more sensitive and
在表面游得更快 使它成为更有效的抗生素
zero in on surfaces faster, which could make it even an more efficient antibiotic.
这期的科学秀是由众筹网站的各位赞助者赞助
This episode of SciShow is brought you by all those patrons on Patreon who give us a
以至于我们能免费提供给大家
little bit of money so that we can make this free for everybody.
如果你想帮我们一把 你可以登录patreon.com/scishow
If you want to help us out, you can go to patreon.com/scishow­.
如果你只是想用过观看视频帮我们 你可以登录youtube.com/scishow并关注我们!
And if you just want to help us out by watching, you can go to youtube.com/scishow and subscribe!

发表评论

译制信息
视频概述

科普视频。注射细菌治病。科学真可怕,科学专业用语更可怕。望大家好好学习,将来我们的命能多长靠你们了!

听录译者

收集自网络

翻译译者

Sallyzhe

审核员

瞌睡虫儿

视频来源

https://www.youtube.com/watch?v=TVYAp-bP_rE

相关推荐