Circular Dichroism Spectroscopy for Protein Structural Analysis

[@debesray]

Describing using animation was fantastic for a clear understanding, which we miss in the papers or articles. Thank you.

[@SpartanTutorials]

Most welcome, Debes. Glad to know you found it helpful.

[@viktorija400]

This really helped me understand this study. I was reading it before I watched the video and I was very confused, and now that I watched the video it is very clear how it all works. Thank You !!

[@SpartanTutorials]

My pleasure Viktorija. Glad to know you found it helpful.

[@MajaMika-g5n]

found this video very helpful, since there are no studies on CD in my native language and reading an english article provided by my prof (chemistry student here) didn’t make sense to me. thanks a lot! hopefully i’m gonna pass my test thanks to your video

[@SpartanTutorials]

Glad to know it helped; Best wishes!

[@mthakur1987]

nice information gathered to talk on CD. Keep it up

[@umarhasnain7369]

15:31, why is this dotted line inactive?? How will I understand that??

[@SpartanTutorials]

The dotted line is not inactive. It is the CD spectrum of an inactive protein. The protein mutant used in the analysis is inactive and has lost its activity. This loss of activity is confirmed by other assays.

[@kaiser7364]

From wich article is the figures at 15:15?

[@SpartanTutorials]

Source: Kelly SM, Jess TJ, Price NC. How to study proteins by circular dichroism. Biochim Biophys Acta. 2005 Aug 10;1751(2):119-39. doi: 10.1016/j.bbapap.2005.06.005. PMID: 16027053.

[@maksimnovikov4238]

Thanks a tonn!! Are there any other CD resourses you recomend? Especially for cofactor binding?

[@SpartanTutorials]

Thank you Maksim. Here are a few resources for studying cofactor binding using CD:
www.researchgate.net/publication/7304807_Probing_Protein_Binding_Sites_by_Circular_Dichroism_Spectroscopy
www.sciencedirect.com/science/article/pii/S0005273613002083
ctrstbio.org.uic.edu/manuals/kelly.pdf

[@shraddhabose3330]

very nice! well explained. which buffer do we need for CD run? I think 20-50uL of 0.2-0.5mg/mL concentrated protein is required right?

[@SpartanTutorials]

Thanks! You'd need at least 150 uL for a 1 mm path length cuvette. Regarding protein concentration, 0.2-0.5 mg/mL is a good start. However, it may vary depending on the secondary structure content. You can start with a concentrated protein solution and dilute accordingly. Check out the following links for more details:
1. www.ncbi.nlm.nih.gov/pmc/articles/PMC2728378/
2. cmi.hms.harvard.edu/files/cmi/files/cmi_cd_getting_started.pdf
3. structbio.vanderbilt.edu/wetlab/cd.sample.prep.php

[@shraddhabose3330]

@@SpartanTutorials Thanks a lot! Truly appreciate your help.

[@ryoichitaguchi232]

Thank you so much for this!

[@ABR_83]

Great video. How do I normalise my data by the number of peptide bonds?

[@SpartanTutorials]

Thanks Andrea. I'm not quite sure, but here is a resource that may be helpful:
Greenfield, N. J. (2004). Analysis of Circular Dichroism Data. Numerical Computer Methods, Part D, 282-317. doi:10.1016/s0076-6879(04)83012-x

[@khushalithaker9507]

Helped a lot... Thank you sooooooo much sir!

[@SpartanTutorials]

Most Welcome Khushali!

[@kajalguleria7615]

Thank u so much sir..this was best explaination

[@SpartanTutorials]

Most welcome, Kajal. Glad you found it helpful.

[@samarthkumar5198]

Sir,
How can we study conformational changes in a protein structure?(Except the conventional techniques we have)

[@SpartanTutorials]

Well, we can study them using techniques like FRET and doing crystallography of different conformations. Additionally, there are more specialized techniques. Take a look here - en.wikipedia.org/wiki/Conformational_change

[@atul281979]

great job very nice

[@SpartanTutorials]

Thank you!

[@hanumanthpanuganti5185]

Thank you sir

[@SpartanTutorials]

Most welcome Hanumanth.

[@matildeermanni7790]

thank you

[@SpartanTutorials]

Glad you found it helpful.

[@manishachauhan7046]

👏

[@SpartanTutorials]

Thanks Manisha.