Your lectures are helping me a lot in my high school biology studies. You are far better than many of teachers and also many expensive books. Thanks for this noble work.
Cheers for this, I have been researching "mitochondrial health assay" for a while now, and I think this has helped. Have you ever come across - Miyason Mitochondria Masker - (should be on google have a look ) ? Ive heard some extraordinary things about it and my mate got excellent success with it.
Thank you so much for these amazing and extremely helpful videos.These videos are my only hope for passing my biochemistry class. I wish my professor was this good.
I just want to say thank you so much, I don't know what I would do without your Biochem videos, your teaching is so much better than my awful University professors. I Donated money as a thank you
Thank you so much for your superb lectures. You're the reason I'm acing my tests in biochemistry. Would you please talk about ketone bodies formation and their regulatory effects.
you are just amazing! i have been listening to your lectures for over a year now and you explain better than my professors! thanks keep up the great work! do you have any lectures on immunology?
Hi...may I ask, in complex 1, where do the 2 H+ ions taken up by FMN to form FMNH2 go to? Are they passed on to the iron sulfur clusters to regenerate FMN? And where do those 2 H+ ions ultimately end up? Thank you!
For Complex I, I think your schematic diagram can be drawn a bit better to show that the active site is actually on the left side of the enzyme (still in the membrane though). The way you have it depicted is where the active site was previously thought to be. Good video overall!
This is amazing, thank you so much. What happens to the protons in FADH2 in complex 2? In the other complexes it seems that only electrons are transferred to Fe-S centers, which then donate the e- to Q, which usually pull ADDITIONAL H+ from matrix; however, since complex 2 doesn't involve proton pumping, does that mean that both electrons and protons from FADH2 eventually end up combining with ubiquinone to make ubiquinol? In other words, does ubiquinone in this case NOT pull additional H+ from matrix, UNLIKE in complex I and III?
The FADH2 protons are most likely to move towards the negatively charged matrix - rich in conjugate bases - to combine later on with the the reduced CoQ to form CoQH2 (ubiquinol) . The same story is true for NADH + H in complex I . Lord knows best !!!!
Madalina Nistorescu it is simply because the electron flow in the complex II is not making enough electron potential difference to make complex 2 the proton pump,like we have in complex 1 :) hope this helped :)
Complex II is NOT a transmembrane protein spanning the phospholipid bilayer of the inner mitochondrial membrane ; so its conformational change during electron transport does NOT convey protons H+ from the mitochondrial matrix towards the intermembrane space ! Complex II is rather a membrane bound mitochondrial enzyme of the citric acid cycle - (TCA) cycle - called (succinate dehydrogenase) ; whose reduced FADH2 coenzymes transport their electrons readily to UBIQUINONE (CoQ) inorder to reach complex III .
Hi ak lectures, you're amazing.... i have one doubt regarding complex 1 you told in lecture that 4 ions transfer matrix to inter mitochondrial space........ why only 4? why not 2?
It mean if proton which attaches to the ubiqounone to reduce it to ubiqouinol is coming from matrix then the proton which is attach to FMN then it will have 2 +positive changre on it bcz only electron are going toward ubiquone not the proton?
Hi Can I ask how many ATP molecules are produced in every ETC complex? It was actually raised by our professor, according to him, every complex in the electron transport chain produces a particular amount of ATP.. He wants us to identify the ATP molecules produced in: Complex I Complex II Complex III Complex IV. Thank you so much for those who can help☺️
How is FMNH2 converted back to FMN after up taking the two protons and after both electrons move to the Fe-S? Do the protons just get released back into the matrix?
At 7:53, you say that complex 2 is responsible for extracting electrons from FADH2 but then go on to say that you extract 2 H's and 2 electrons from the Succinate. So wouldn't succinate technically be the electron source?
I am slightly confused by this particular lecture. In other media and books the ETC is sometimes depicted having Complex I sending the electrons to Complex II and THEN the electrons get passed through the ubiquinone, however, here you say that Complex I passes the electrons to ubiquinone and then the electrons go to Complex II where they interact with ubiquinone again. Is this a mistake or is this correct? Also, FANTASTIC videos. I cant say how much I appreciate your hard work.
Sorry if I'm late, but what he is saying here is correct but i think you got it a little mixed up. Complex I makes use of NADH, whereas complex II makes use of FADH2. They are both fundamentally different. This is due to the succinate dehydrogenase in complex II. He mentioned that complex I passes the electrons to ubiquinone, Q, and is converted to QH2 with the uptake of 2H+ from the matrix. Complex II obtains the electrons from FADH2, and the electrons are directly accepted by Q After QH2 is formed, it goes to complex III. Hope it answers your question! ~_~
God bless you as you have blessed us students all over the world.
Your lectures are helping me a lot in my high school biology studies. You are far better than many of teachers and also many expensive books. Thanks for this noble work.
Cheers for this, I have been researching "mitochondrial health assay" for a while now, and I think this has helped. Have you ever come across - Miyason Mitochondria Masker - (should be on google have a look ) ? Ive heard some extraordinary things about it and my mate got excellent success with it.
these vids will get me thru med school lol
same
med school?? we’re learning this at undergraduate school
@@destinydiamond1282 The first two years of med school is relearning this stuff in a clinical context lol
I honestly love the way you explain the biochemestry. Everything makes sense. Thank you so much. You actually helped me a lot .
I literally don't go to my biochem lecture in order to watch these videos. Amazing stuff. Thank you so much for helping me through this class.
from 2024 and your lectures are saving me for finals thank you very much from whole heart
U are the man version of lehninger book. Huge respect.
you're amazing my friend and for some reason you remind me of Leonardo dicaprio, because of your tone of voice and your hand gestures haha.
Thank you so much for these amazing and extremely helpful videos.These videos are my only hope for passing my biochemistry class. I wish my professor was this good.
I hear ya! Glad to help :) good luck on your final!
I just want to say thank you so much, I don't know what I would do without your Biochem videos, your teaching is so much better than my awful University professors. I Donated money as a thank you
Thank you SO MUCH for your fantastic lectures! they make my preparation for the USMLE step 1 much easier and so enjoyable!
You have your own way to make everything you teach makes sense to us.. if you were my lecturer I would always score merits in biochemistry
this AK is AK-47 of biochemistry !
you're right!
thank u soo much...you are my life saver and my angel....may god bless u with all happiness and good health ...u have won our hearts
Thanks a lot AK. You are my savior in biochemistry. Everyone in from my class loves your lectures.
Your one of a kind AK...Your lectures are very helpful!
Can I just say "Thank you"? Studying rn for an exam and this lecture is very well done.
Watching these on x2.0 speed because my test is tomorrow lol
😂
My test is today
Bro just made me ready to face biochemistry for my entire life thank you❤
Your videos saved my biochemistry exam grade big time! Thank you so much for sharing!
Thankyou very much for making these video lectures, these are better than my professeurs and my expensive books
This is the best explanation I´ve ever heard! I wish my profs would be so good.... -.- Thank you!
forever grateful for this man
The Succinate DeH and Complex II system finally just clicked for me, thank you!!!
I haven't taken the mcat yet but I cry of happiness for saving me tons of headaches!
You help me to love biochemistry more. Can you do another video on inhibitor that inhibiting the complexes in the respiratory chain? thanks in advance
Probably not. The man is doing his residency right now
Thanks alot for your great job, and how you could simplify ETC complex concept.
I love you
excellent
You’re helping me a lot with your lectures. Thanks!
Thank you so much for your superb lectures. You're the reason I'm acing my tests in biochemistry. Would you please talk about ketone bodies formation and their regulatory effects.
you are just amazing! i have been listening to your lectures for over a year now and you explain better than my professors! thanks keep up the great work! do you have any lectures on immunology?
You do great work for all medical students 👌🌿thanks for you
Thank you so much for the upload and it is really helpful!
Thanks brother, amazing lecture A++
This is excellent and so thorough.
Your explanations are great, you have a very clear, loud and well pronounced voice. Thank you very much! +subscribed and liked. :)
Thank you so much AK LECTURES
where do the H+ ions from the FADH2 go when complex II oxidates it to FAD?
thank you from the bottom of my heart
Superb Explanation 💛💛💛
Hi...may I ask, in complex 1, where do the 2 H+ ions taken up by FMN to form FMNH2 go to? Are they passed on to the iron sulfur clusters to regenerate FMN? And where do those 2 H+ ions ultimately end up? Thank you!
I have the same doubt
You are a great teacher 🙏
For Complex I, I think your schematic diagram can be drawn a bit better to show that the active site is actually on the left side of the enzyme (still in the membrane though). The way you have it depicted is where the active site was previously thought to be.
Good video overall!
do the two protons from FADH2 get transferred to Q along with the two electrons? Or is it like complex 1 where Q picks them up from the matrix?
+Herman Kazakov Around 40 seconds into his next video he states that the two H's from FADH2 are bound to ubiquinone.
Thank you great work 👏👏👏👏👏
Thanks for your work
Thank you!
This is amazing, thank you so much.
What happens to the protons in FADH2 in complex 2? In the other complexes it seems that only electrons are transferred to Fe-S centers, which then donate the e- to Q, which usually pull ADDITIONAL H+ from matrix; however, since complex 2 doesn't involve proton pumping, does that mean that both electrons and protons from FADH2 eventually end up combining with ubiquinone to make ubiquinol? In other words, does ubiquinone in this case NOT pull additional H+ from matrix, UNLIKE in complex I and III?
The FADH2 protons are most likely to move towards the negatively charged matrix - rich in conjugate bases - to combine later on with the the reduced CoQ to form CoQH2 (ubiquinol) .
The same story is true for NADH + H in complex I .
Lord knows best !!!!
Could anyone explain WHY Complex 2 does not pump protons?
Madalina Nistorescu it is simply because the electron flow in the complex II is not making enough electron potential difference to make complex 2 the proton pump,like we have in complex 1 :) hope this helped :)
Complex II is NOT a transmembrane protein spanning the phospholipid bilayer of the inner mitochondrial membrane ; so its conformational change during electron transport does NOT convey protons H+ from the mitochondrial matrix towards the intermembrane space !
Complex II is rather a membrane bound mitochondrial enzyme of the citric acid cycle - (TCA) cycle - called (succinate dehydrogenase) ; whose reduced FADH2 coenzymes transport their electrons readily to UBIQUINONE (CoQ) inorder to reach complex III .
Thanks for this noble work
succ. btw useful as always
its very very helpful to me sir.. from kolkata :)
In lehningers book,it is written that q gets 2 hydrogens from NADH2 in complex 1
Amazing instruction
Thank you so much !
Thank you so much, was so confused before
you are the best!!
best explanation ever
doing gods work, thank you so much
thank you so much. you really help me a lot!
you made it quite easy for us :)
omg can you come to my uni and be my lecturer? Damn you are so good at teaching! keep it up mate
Hi ak lectures, you're amazing.... i have one doubt regarding complex 1 you told in lecture that 4 ions transfer matrix to inter mitochondrial space........ why only 4? why not 2?
I was wondering the same thing.
Love you AK from Australia
It mean if proton which attaches to the ubiqounone to reduce it to ubiqouinol is coming from matrix then the proton which is attach to FMN then it will have 2 +positive changre on it bcz only electron are going toward ubiquone not the proton?
Thank you sir and God bless you 😇😊
Good Job❤❤
Can someone please tell me how the H+ ions are pumped out into the intermembrane space if they hang on to Ubiquinone and reduce it??
Hi
Can I ask how many ATP molecules are produced in every ETC complex?
It was actually raised by our professor, according to him, every complex in the electron transport chain produces a particular amount of ATP..
He wants us to identify the ATP molecules produced in:
Complex I
Complex II
Complex III
Complex IV.
Thank you so much for those who can help☺️
In 1st complex, why/how 4H+ ions are pumped from the matrix to the intermembrane?
Have u gotten the answer of the question,cz i m also confused
I need the answer too...
so why is complex II called succinate reductase although it causes succinate to be oxidised ?
life saviour......thank you..
Excellent lecture
crystal clear! thanx
Brilliant guy !
great lecture
ur the goat
Are complexes I and II simultaneously reducing different CoQ molecules? It doesn't appear like they're sequential.
is that the second protein complex the same which we discussed during the tranport of cytosolic NADH because i m little bit confused
Osm explanation thanks alot😘😘😘
How is FMNH2 converted back to FMN after up taking the two protons and after both electrons move to the Fe-S? Do the protons just get released back into the matrix?
Yes. It's probably pumped out via Na+/H+ pump to the matrix so it can be reused by CoQ.
Yes. It's probably pumped out via Na+/H+ pump to the matrix so it can be reused by CoQ.
At 7:53, you say that complex 2 is responsible for extracting electrons from FADH2 but then go on to say that you extract 2 H's and 2 electrons from the Succinate. So wouldn't succinate technically be the electron source?
what happens to the oxidised FAD in complex II, does it remain attached or detaches after a period of time?
I am slightly confused by this particular lecture. In other media and books the ETC is sometimes depicted having Complex I sending the electrons to Complex II and THEN the electrons get passed through the ubiquinone, however, here you say that Complex I passes the electrons to ubiquinone and then the electrons go to Complex II where they interact with ubiquinone again. Is this a mistake or is this correct?
Also, FANTASTIC videos. I cant say how much I appreciate your hard work.
Sorry if I'm late, but what he is saying here is correct but i think you got it a little mixed up. Complex I makes use of NADH, whereas complex II makes use of FADH2. They are both fundamentally different. This is due to the succinate dehydrogenase in complex II. He mentioned that complex I passes the electrons to ubiquinone, Q, and is converted to QH2 with the uptake of 2H+ from the matrix. Complex II obtains the electrons from FADH2, and the electrons are directly accepted by Q After QH2 is formed, it goes to complex III. Hope it answers your question! ~_~
I've noticed that all over the place too. But this video is correct; Complex 1 and 2 send their electrons to ubiquinone.
You are awesome man
Thanks alot ❤😍..i shared the vedio
i wonder whether complex II is called succinate reductase or succinate Q reductase. please see 9:19
The saviour
thank you !!
great content!
It is NADH that comes in and is converted to NAD+ + H+
nice job dude
your good. you know your biochemistry.
+Just Observing thanks bud
Which complex is more efficient | or || ?
why complex 2 is not the proton pump, what's the reason?
YOU ARE AMAZINGGGGGGG
thanks
Thank u sir
Straight from the BRONX, real hood shit
*BROOKLYN ;-)
Are complex 1 and 2 are proteins by structure?
yes, all except CoQ are protiens, even cytochrome C is a protein
great !!