Name: 過氧物酶體的結構與功能 (Peroxisomes Structure & Function)
Uploaded: 2025-04-13T03:15:15.000Z
Duration: 16 min 24 s

In this video today, we're going to be talking about the structure and function of paroxysms.

在今天的視頻中，我們將討論陣發性痙攣的結構和功能。

Before we get started, if you guys like this video, it makes sense, it helps you, please support us.

在我們開始之前，如果你們喜歡這個視頻，它有意義，對你們有幫助，請支持我們。

One of the best ways that you can do that is by hitting that like button, comment down in the comment section, please subscribe.

最好的方法之一就是點擊 "喜歡 "按鈕，在評論區發表評論，並請訂閱。

Also, got some great notes, illustrations to follow along with.

此外，還有一些很好的註釋和插圖可供參考。

Go check that out on our website, we'll have a description box in the link below to follow along with us.

請到我們的網站上查看，我們將在下面的鏈接中設置一個說明框，以便您與我們一起關注。

So they're kind of a spherical membrane, so they have a membrane that encloses their actual contents inside of them.

是以，它們是一種球形膜，所以有一層膜將實際內容物包裹在裡面。

And they have four particular functions, this is what I want you to remember.

它們有四種特殊功能，我希望你們記住這一點。

So they're hollow, spherical, very interesting organelles that, again, play a role in four particular functions.

是以，它們是中空、球形、非常有趣的細胞器，同樣在四種特殊功能中發揮作用。

One is fatty acid oxidation, second one, hydrogen peroxide metabolism, third one, ethanol metabolism, and the fourth one is biosynthetic function of particular lipids.

一是脂肪酸氧化，二是過氧化氫代謝，三是乙醇代謝，四是特定脂質的生物合成功能。

All right, first one, fatty acid oxidation.

All we do with fatty acids, I don't want to get too crazy here because we'll cover this more in biochemistry, but fatty acids can actually naturally be metabolized by a very cool organelle that we've already discussed called the mitochondria.

對於脂肪酸，我不想說得太多，因為我們會在生物化學中詳細介紹，但實際上，脂肪酸可以通過一個很酷的細胞器進行自然代謝，我們已經討論過這個細胞器，叫做線粒體。

So when we talked about the mitochondria, we said one of the things that occurs is something called beta oxidation, and then the mitochondria.

是以，當我們談到線粒體時，我們說過其中發生的一件事叫做β氧化，然後是線粒體。

All it means is we take this fatty acid into the mitochondria, and it goes through this process of oxidation, hydration, and again, more oxidation, and then what's something called thylation, and you make something called acetyl-CoA.

這意味著，我們將脂肪酸帶入線粒體，經過氧化、水合、再氧化、再水合的過程，然後進行所謂的 "乙基化"，最後生成乙酰-CoA。

And then what happens with the acetyl-CoA is generally in the mitochondria, it'll go through the electron, it'll actually go through the Krebs cycle, generate NADHs, FADH2s, and then from there, you can make something like energy, well, particularly FADH2s, NADHs, they can utilize in the electron transport chain to make ATP.

然後，乙酰-CoA 一般會在線粒體中通過電子，實際上是通過克雷布斯循環，產生 NADHs 和 FADH2s，然後從那裡，你可以製造出類似能量的東西，特別是 FADH2s 和 NADHs，它們可以在電子傳遞鏈中利用來製造 ATP。

So when we take this fatty acid and we make acetyl-CoA, this is called beta oxidation.

是以，當我們吸收這種脂肪酸並製造乙酰-CoA 時，這就是所謂的 beta 氧化。

Now, the same thing can happen in peroxisomes, but in peroxisomes, these are called very long-chain fatty acids.

現在，同樣的情況也會發生在過氧物酶體中，但在過氧物酶體中，這些脂肪酸被稱為超長鏈脂肪酸。

And then over here, we have another one called branch-chain fatty acids.

這裡還有一種叫做支鏈脂肪酸的物質。

These will actually get taken into peroxisomes.

這些物質實際上會被帶入過氧物酶體。

And what happens is the very long-chain fatty acids, they'll go through the same kind of So you'll break them down into two carbon chains at a time.

長鏈脂肪酸也會經歷同樣的過程，一次分解成兩條碳鏈。

And when that happens, again, this process here is called beta oxidation.

當這種情況發生時，這個過程同樣被稱為β氧化。

So they can occur in both the mitochondria and the peroxisomes.

是以，線粒體和過氧物酶體中都可能存在這些物質。

The big thing is for peroxisomes, it occurs to very long-chain fatty acids.

對於過氧物酶體來說，最大的問題是它會產生非常長鏈的脂肪酸。

And again, the basic concept is you do oxidation, hydration, oxidation, and something called phylation.

同樣，基本概念是進行氧化、水合、氧化，以及一種叫做 "分化 "的過程。

We'll talk about that a little bit more in biochemistry.

我們會在生物化學中再多講一點。

But the other thing is the branch-chain fatty acids.

So the branch-chain fatty acids, when they get brought into the actual peroxisome, they actually go and you cut those branches off.

是以，當支鏈脂肪酸被帶入實際的過氧物酶體時，它們實際上會被切斷。

So when you cut the branches off to turn them into a very long-chain fatty acid with no branches on them, this process is called alpha oxidation.

是以，當你把這些分支切掉，把它們變成沒有分支的長鏈脂肪酸時，這個過程就叫做α氧化。

So there's two particular processes that are going to occur here in the actual peroxisomes.

是以，在實際的過氧化物酶體中會發生兩個特殊的過程。

One is beta oxidation of very long-chain fatty acids.

一種是超長鏈脂肪酸的β氧化。

And the second one is alpha oxidation of branch-chain fatty acids into very long-chain fatty acids.

第二種是將支鏈脂肪酸氧化成超長鏈脂肪酸。

You cut these things off two pieces at a time, these very long chains.

你一次要把這些東西切成兩段，這些鏈子很長。

You cut them into two carbon segments called acetyl-CoA.

你將它們切割成兩個碳段，稱為乙酰-CoA。

And generally, you make something called acyl-CoA, which is just a long, again, carbon chain.

一般來說，你會製造出一種叫做酰基-CoA 的東西，也就是一條長長的碳鏈。

So if this was 16 carbons, it would be 14 carbons.

是以，如果這是 16 個碳原子，就會變成 14 個碳原子。

And these generally, they just go back up.

And they continue this vicious cycle until you've broken the entire fatty chain down.

這種惡性循環會一直持續下去，直到你把整個脂肪鏈都分解掉。

This is important, particularly in which organelle?

這一點很重要，尤其是在哪個細胞器中？

So one of the functions of peroxisomes is to break down very long-chain fatty acids into acyl-CoA, and then usually one of these molecules that's, again, just two carbons shorter of this very long-chain fatty acid.

是以，過氧物酶體的功能之一就是把長鏈脂肪酸分解成酰基-CoA，然後通常會分解出其中一種分子，也就是這種長鏈脂肪酸的兩個碳原子。

Or you take branch-chain fatty acids and cut the branches off and make it into very long-chain fatty acids.

或者將脂肪酸的分支鏈切斷，使其成為長鏈脂肪酸。

The second function that I want you guys to understand here is hydrogen peroxide metabolism.

我想讓你們瞭解的第二個功能是過氧化氫代謝。

So this one's actually really interesting.

所以，這個問題其實很有意思。

So in the same concept here, you take in these molecules here.

是以，同樣的概念，你在這裡吸收這些分子。

So we're going to call one of these, this is our branch-chain fatty acid.

是以，我們將其中的一種稱為支鏈脂肪酸。

And we said we also bring the other one in, which is the very long-chain fatty acids.

我們說，我們還引入了另一種物質，即長鏈脂肪酸。

We said that generally, these will undergo a beta-oxidation process.

我們說過，一般情況下，這些物質會經歷一個β-氧化過程。

And what happens is you make something, you make two molecules, right?

然後你就會製造出兩個分子，對吧？

One is you make acetyl-CoA, and the other one is you make acyl-CoA, and we said all that does is it just goes back and gets recycled, right?

一個是製造乙酰-CoA，另一個是製造酰基-CoA，而我們說過，所有這些都會被回收利用，對嗎？

This process here is called beta-oxidation.

The next one is we take the branch-chain fatty acids and we break them down into very long-chain fatty acids.

其次，我們將支鏈脂肪酸分解成長鏈脂肪酸。

What's really interesting is that in order for us to be able to take these very long-chain fatty acids and to do this process here to make these two molecules, we actually have to use water during the hydration or hydrolysis step.

真正有趣的是，為了讓我們能夠提取這些長鏈脂肪酸，並在這裡完成製造這兩種分子的過程，我們實際上必須在水合或水解步驟中使用水。

And what that does is that takes water and oxygen and uses it in this step to make something called hydrogen peroxide.

它的作用是利用水和氧氣，在這個步驟中生成一種叫做過氧化氫的東西。

Hydrogen peroxide is actually a nasty free radical, so it has the ability to cause free radical molecules which can cause a lot of damage to proteins and DNA and membranes.

過氧化氫實際上是一種令人討厭的自由基，是以它有能力造成自由基分子，從而對蛋白質、DNA 和薄膜造成嚴重破壞。

So how do we actually prevent this thing from continuing to form?

那麼，我們究竟該如何防止這東西繼續形成呢？

這種粉紅色的酶被稱為過氧化氫酶。

And what catalase does is it takes the hydrogen peroxide that was formed and just converts it right back into water and oxygen.

過氧化氫酶的作用是將形成的過氧化氫直接轉化為水和氧氣。

So we take the free radical, which is nasty, and turn it back into water and oxygen, which is actually okay.

是以，我們把令人討厭的自由基變成了水和氧氣，這實際上是沒有問題的。

So that's the big things that I really want you to remember here for this particular molecule is the catalase.

是以，我希望你們記住這個特殊分子的主要成分是過氧化氫酶。

You can actually take from, you know what's called your electron transport chain?

From your electron transport chain, when you take FADHs and NADHs, these will actually work on the electron transport chain and generate things like free radicals.

從電子傳遞鏈中獲取 FADHs 和 NADHs 時，這些物質實際上會作用於電子傳遞鏈，併產生自由基等物質。

And these hydrogen peroxide molecules can actually go here and get converted into water and oxygen as well.

這些過氧化氫分子實際上可以在這裡轉化成水和氧氣。

So this is really important for preventing free radicals.

是以，這對防止自由基的產生非常重要。

So again, one thing I want you to remember here is that hydrogen peroxide is what we refer to as a free radical, and it can cause a lot of damage.

所以，我想讓你們記住的一點是，過氧化氫就是我們所說的自由基，它會造成很大的傷害。

So this has the ability to damage proteins and cell membranes and DNA.

是以，它能夠破壞蛋白質、細胞膜和 DNA。

We do not want that, so that's what peroxisomes help to prevent.

我們不希望出現這種情況，是以過氧物酶體有助於防止這種情況的發生。

Okay, so we got fatty acid oxidation, beta oxidation of very long chain, alpha oxidation of branched chains.

好了，我們有了脂肪酸氧化、長鏈的β氧化和支鏈的α氧化。

We got hydrogen peroxide metabolism via catalases and preventing free radical reactions.

我們通過過氧化氫酶進行過氧化氫代謝，防止自由基反應。

The other two functions, my friends, are actually pretty cool, and they kind of coordinate with something called the smooth ER, which you guys better remember.

我的朋友們，另外兩個功能其實很酷，它們與一個叫 "平滑急診室 "的功能相協調，你們最好記住這個功能。

So you guys remember the smooth endoplasmic reticulum?

We said that one of the functions is that they play a role within lipid synthesis, right?

我們說過，它們的功能之一是在脂質合成過程中發揮作用，對嗎？

They synthesize phospholipids, they synthesize steroids, particularly steroid hormones, right?

它們合成磷脂，合成類固醇，尤其是類固醇激素，對嗎？

Well, they can actually derive from cholesterol.

So you can take cholesterol, you can make steroid hormones, sex hormones, bile salts, lipoproteins, all that stuff.

是以，你可以攝取膽固醇，可以製造類固醇激素、性激素、膽汁鹽、脂蛋白，所有這些東西。

Peroxisomes actually have the ability to do that as well.

實際上，過氧物酶體也有這種能力。

So one of the things I want you to remember is the smooth endoplasmic reticulum does help with making things like what?

所以，我希望你們記住的一件事是，光滑的內質網確實有助於製造像什麼這樣的東西？