You are the best chemistry teacher I have experiences in my entire life. You explained in 10 minutes what a teacher from my university with mlre than 20 years of experience could not explain in one hour clearly. Hands down my friend hands down indeed.
Thank you so much for sharing these very thorough lectures! Very glad I came across these - so concise and well thought out, I can more fully appreciate how our bodies operate! You have quite a gift for teaching!
I'm from algeria and I'll pass my Bac in 1 week , I've been chearchig for the analysis of this experiment and the meaning of the result of each steps of it , I'm not even fluent in english and I understood everything OMG THANK YOU SO MUCH .
I'm a French student and listening to your videos helps me a lot to understand !! you explain very well and you speak Also very well which helps me to understand. Thanks a lot !! You save my test
OK, so....... This is my summary, if I am wrong about something, please correct me. Christian Anfinsen used RNAase A (an enzyme that breaks down RNA, it's structure has 4 disulfide bridges between 8 pairs of cysteine sidechains), UREA (A polar substance that can disrupt the Hydrogen bonding of the 3 dimensional enzyme) and Beta Mecraptoethanol (a reducing agent that is capable of breaking disulfide bridges between a a pair Cysteine Side chains). Of course, he calculated the normal enzyme activity before starting the experiment. Trial #1 He placed RNAase A sample in Urea, which denatured the enzyme by changing it's tertiary structure, as a result the active site shape is altered, so it no longer fitted the substrate (RNA). Enzyme activity was 0% in Urea. Urea was removed through dialysis, the enzyme activity was brought back to 100%. TRIAL #2 He placed RNAase A in a High concentration of BETA Mecroptoethanol, this also caused enzyme to denature, and now it no longer fits the substrate and activity was 0%. Upon removal of the reducing agent, disulfide bridges were "rebuilt" (because the normal environment is oxidizing), which brought enzyme activity back to 100%. TRIAL #3 It started like TRIAL #2, but this time, Urea was present so when the Beta Mecroptoethanol was removed, disulfide bridges formed between the wrong pairs of cysteine side chain. Even after Urea was removed, the enzyme activity was back to only 1%, so the wrong structure was maintained, except for a minuscule number of enzyme, which Afinsen Hypothesized was due to the random nature of protein folding TRIAL#4 He added a small concentration of Beta mecraptoethanol to the solution in TRIAL #3, with the Urea removed. This allows disulfide bridges to break and reform in the same mixture. The old structure was not restored in a matter of seconds, in fact, it took 10 hours for the enzyme activity to reach 90% it's normal activity. Conclusion Urea shifts equilibrium the folded state, to the unfolded state of RNAase A. Disulfide bridges help reinforce the structure of the enzyme. Don't smoke weed.
So the native ribonuclease reformed because it is thermodynamicly stable got that. But how does the beta-mercoptoethanol not just keep breaking the disulfide bonds after they formed? Is it used up or something?
In experiment 3. The resulting solution was similar to that of experiment 2 where urea was still present. How then was the activity or protein structure fully recovered since urea breaks down hydrogen bonds?
Wrong way to folding can change nothing . I have solved the problem, but unfortunately I have met a conceited Science editor. She know nothing about refolding. The key is "freezing".
You are the best chemistry teacher I have experiences in my entire life. You explained in 10 minutes what a teacher from my university with mlre than 20 years of experience could not explain in one hour clearly. Hands down my friend hands down indeed.
CHIRRIN GARCIA thanks! appreciate that :)
all your videos are some of the best explanations ever! please continue making these, thankyou!.
Thank you so much for sharing these very thorough lectures! Very glad I came across these - so concise and well thought out, I can more fully appreciate how our bodies operate! You have quite a gift for teaching!
This was extremely helpful. Thank you so much for the clarity of the content as well as the explanation.
This lecture is amazing and SO EASY to understand. Thank you so much!
I love your videos. Thank you so much; you've helped me a lot in my tests & finals. Keep up the good work👍
Great Lecture , You help me more than my teacher.
I couldn't find information about this experiment through other webpages but by listening your lectrue i could solve what i wanted. Thank you so much.
Well broken down and those graphics really helped me visualise and understand better! THANKYOU ^^
So clear and so helpful, even for strangers, thank you !
I'm from algeria and I'll pass my Bac in 1 week , I've been chearchig for the analysis of this experiment and the meaning of the result of each steps of it , I'm not even fluent in english and I understood everything OMG THANK YOU SO MUCH .
You explained it really well. Thank you!
This was amazing. God bless you.
Fantastically explained which made me to understand the concept very well.....Thanks buddy...!!
Very well explained, you really saved me a lot of time, thank you so much.
Thank you sooo much! I finally understood everything. You're the best!
Greetings from Serbia :)
Very clear and helpful explanation. Thank you!!
Thank you so much! B-) it was a little difficult to understand by just reading the journal, you've explained it really well.
This video was very clear to understand the protein folding. Thank you so much.
thank you AK LECTURE
I'm a French student and listening to your videos helps me a lot to understand !! you explain very well and you speak Also very well which helps me to understand. Thanks a lot !! You save my test
Thank you for the explanation!
Brilliant Summary!
beautiful explanation
exactly what i was looking for!!!! thank you!!!
Thanks for making it comprehensive
Awesome!! Thanks so much. I was was confused before but now I get it. :)
Thank you so much! Better than my textbook.
Thanks. Extremely good explanation. Nice teaching 👍
Great explanation 🙌🏾
U have made biochem soo easy..thank u
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great work
Well explained thank you ❤🎉
This is great, thank you so much! The textbook was so confusing on this topic. I'm definitely subscribing.
Thanks Alex, glad to hear it! :)
God bless you for this ...
omg this really came in clutch for my bio midterm in 3 hrs lmao
extremely good
This is awesome!
OK, so....... This is my summary, if I am wrong about something, please correct me.
Christian Anfinsen used RNAase A (an enzyme that breaks down RNA, it's structure has 4 disulfide bridges between 8 pairs of cysteine sidechains), UREA (A polar substance that can disrupt the Hydrogen bonding of the 3 dimensional enzyme) and Beta Mecraptoethanol (a reducing agent that is capable of breaking disulfide bridges between a a pair Cysteine Side chains). Of course, he calculated the normal enzyme activity before starting the experiment.
Trial #1
He placed RNAase A sample in Urea, which denatured the enzyme by changing it's tertiary structure, as a result the active site shape is altered, so it no longer fitted the substrate (RNA). Enzyme activity was 0% in Urea. Urea was removed through dialysis, the enzyme activity was brought back to 100%.
TRIAL #2
He placed RNAase A in a High concentration of BETA Mecroptoethanol, this also caused enzyme to denature, and now it no longer fits the substrate and activity was 0%. Upon removal of the reducing agent, disulfide bridges were "rebuilt" (because the normal environment is oxidizing), which brought enzyme activity back to 100%.
TRIAL #3
It started like TRIAL #2, but this time, Urea was present so when the Beta Mecroptoethanol was removed, disulfide bridges formed between the wrong pairs of cysteine side chain. Even after Urea was removed, the enzyme activity was back to only 1%, so the wrong structure was maintained, except for a minuscule number of enzyme, which Afinsen Hypothesized was due to the random nature of protein folding
TRIAL#4
He added a small concentration of Beta mecraptoethanol to the solution in TRIAL #3, with the Urea removed. This allows disulfide bridges to break and reform in the same mixture. The old structure was not restored in a matter of seconds, in fact, it took 10 hours for the enzyme activity to reach 90% it's normal activity.
Conclusion
Urea shifts equilibrium the folded state, to the unfolded state of RNAase A.
Disulfide bridges help reinforce the structure of the enzyme.
Don't smoke weed.
very good explanation.
Thank you for the explanation it was very helpful
Thank you
This was amazing thank you!!!!!!!
Thank you !
Thank you so much
Andrey does it again
Best explanation to exist
Amazing!
¡Un maestro!!
Even when english is not my first language!!!
God bless youuuu
you saved me sir!
Hello Mr AK,
Could you please make a video on prions and misfolding
So the native ribonuclease reformed because it is thermodynamicly stable got that. But how does the beta-mercoptoethanol not just keep breaking the disulfide bonds after they formed? Is it used up or something?
HELP!
why ,when proteins are denatured and renatured, they only regain part if their original activity....
Great.
Danke ! Thanks
In experiment 3. The resulting solution was similar to that of experiment 2 where urea was still present.
How then was the activity or protein structure fully recovered since urea breaks down hydrogen bonds?
great .... thanks :)
Could you make one about CRISPR?
Regards and Congratulations from Argentina!
great.... thanks😃😃
sirrrrrr..... this is lit.. im clear asf now rather in lecture hall
Thanku sir
Where is this amazing accent from!
my life was a joke before your videos, can not believe how much I didn't learn in college
I wish i could double triple like your videos
Sir,How will you say ..that disulfide bond made only between cystine..why not methionine??
In experiment 2, how to remove 2-ME only but not simultaneously remove urea?
AK you are excellent lecturer
Thank you!
exelent!
Legend
It took me watching this video to realize my teacher explained this completely incorrectly to 500 kids. Thank you!!
You should be the one I pay the tuition to.
Thanks my broder. I must read the papper but this video is awesome!
PD: Regards to Gatitos de la iglesia 😺
Nyc
I dunno man , i'm going to think that Basically i've understood it all and Basically want to thank you
thanks sir,,,,but please marathi in translation
Wrong way to folding can change nothing . I have solved the problem, but unfortunately I have met a conceited Science editor. She know nothing about refolding. The key is "freezing".
that is nirvana, anything can be better than this
beautiful explanation
Thank you!
Thank you!
Wiem Abidi you're welcome ! :)