Xinji Zhu

11 Questions 8 Answers 0 Followers

Questions related from Xinji Zhu

How to find the optimized condition for Sample preparation for Cryogenic electron microscopy (cryo-EM)?

I am trying to get a protein complex (one is around 110kDa and the other is around 25kDa) for Cryogenic electron microscopy (cryo-EM). The main method I am using is to run the sample through a gel...

29 August 2023 6,785 1 View

Protein sequence by Mass Spec, the coverage is not 100%?

Hi, the coverage for my protein sample after Mass Spec is around 95%. Is there any reason why the coverage is not 100%? Sample purity? some peptides not identified by mass spec? Thank you!

12 March 2020 9,409 0 View

Enthalpy change from differential scanning calorimetry(DSC) without a good baseline?

I am trying to get enthalpy change for thermal unfolding of my protein using differential scanning calorimetry(DSC). The graph was attached below. Instead of two parallel baselines in normal DSC...

23 February 2020 4,907 4 View

Differential Scanning Calorimetry (DSC) protein aggregation?

I am working on Differential Scanning Calorimetry (DSC) for my protein. Mainly I want to check its melting temperature and enthalpy changes. I first tried two standard proteins ( BSA and...

18 February 2020 1,846 3 View

Has anyone use Thiourea or GdnSCN in protein denaturation by circular dichroism?

Hi, I am working on the protein denaturation by circular dichroism. I have tried both GdnHCl and urea and it did not work well. I want to try stronger denaturants, such as GdnSCN and Thiourea....

13 February 2020 8,522 3 View

Polydispersity Index(PDI) in dynamic light scattering(DLS) ?

Hi, I am using DLS to test the size change of my protein in different conditions. the Z-average is around 20nm with PDI around 0.2. I was told that the PDI is too high and the reasonable PDI...

10 July 2019 1,187 11 View

Effect of Glycine betaine on circular dichroism (CD) spectra of protein ?

I am trying to test the effect of Osmolytes on protein folding using circular dichroism. Osmolytes, such sucrose, TMAO and Glycine Betaine are used. I found big background noise when using...

06 June 2019 8,407 4 View

What's relationship between Circular dichroism value and sample volume?

Hi, I am currently using Gdnhcl to analyze folding of my protein. I found the protein reach equilibrium at transition region(1.4M Gdnhcl) very fast(around 3mins). So I decide to use titration...

14 November 2018 857 2 View

What will happen if my primer has a T as ultimate base at the 3' end?

I am starting to design my primers for cloning. In one protocol, it says that avoid a T as ultimate base at the 3' end. I wonder what will happen if I use T as ultimate base at the 3' end. Is it a...

09 November 2015 2,476 1 View

Circular dichroism (CD) value at 222nm and 208nm issue

Hi, I am currently analyzing a thermal denaturation of protein by CD, from the spectra, there are two peaks at around 222nm and 208nm. I know that for a helix, it should have a negative value near...

01 January 1970 3,913 6 View

Can Halophilic protein be considered as Intrinsic disordered proteins(IDPs) in the absence of salt

a lot of halophilic protein is unfolded in the absence of high concentration of salt where most proteins favors the folded state. I wonder if such halophilic protein can be considered as IDPs in...

01 January 1970 8,435 3 View