What is a self intensity test in STD NMR?

Some papers report performing a "STD self intensity" test to check the aggregation of compounds in STD NMR. Can anyone please elaborate how such a test is performed?

07 August 2019 6,832 2 View

What is the correct equation to use when weighing the different chemical shifts of 1H and 15N nuclei in SOFAST HMQC spectra?

I read in the attached paper the equation for HSQC spectra (equation 8). What about HMQC? I cannot find a reference online. Thanks!

04 May 2019 9,770 2 View

Is there a program I can use to align lattice constants of a protein crystal?

I have 2 protein crystal structures and I would like to align their origins so I can then generate the crystal packing of each and compare them.

02 March 2019 917 2 View

After my TEV cleavage site I have a remaining 'am' sequence. Where does this come from?

I am purifying a protein with a his tag. The TEV cleavage site I read is composed of ENLYFQG, and this G remains after cleavage. What I found to also remain is an 'am'. It is before the first...

09 October 2017 1,393 2 View

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I have lysed my e. coli cells (after adding protease inhibitors to the lysis buffer) and freezed the lysate. I then unfroze with the intent of purifying my protein , however due to column...

06 July 2017 4,359 7 View

Has anyone tried to add IPTG to auto inducing media like ZYM? Did you notice an increase in protien expression or is it pointless?

I express using BL21 DE3 e-coli cells and use the ZYM 5052 media. Some colleagues who also use this media have suggested adding IPTG to increase the protein expression. Would that make any sense...

06 July 2017 6,309 3 View

My DNA plasmid purification yielded a 260/280 ratio of 2.15. Why?

After following the exact protocol of the NucleoSpin Plasmid purification kit, I measured the concentration to find the 260/280 ratio 2.15! Any idea what could have gone wrong and how can I fix this?

04 May 2016 2,767 4 View

Can I re-induce protein expression after storage at 4 degrees Celsius?

I was expressing protein in E coli cells at 37 degrees and the OD was 1. I had to store the culture over 3 nights, so I stored it at 4 degrees to prevent over expression. After the 3 nights I...

04 May 2016 3,099 4 View

What's the best way to measure growth rates in House sparrow chicks from day 2 to day 10?

What's the best way to measure growth rates in House sparrow chicks from day 2 to day 10? Since, the growth curve from day 2 to 10 won't be like the "Logistic curve" it might not follow logistic...

03 March 2021 1,401 3 View

No title

02 March 2021 3,060 3 View

Issues with Permeabilization during Flow Cytometry?

Hello Everyone. Currently I am working to characterize macrophages in the myocardium after ischemia-reperfusion injury in rats. Due to the low total cell number isolated from rat hearts I can...

01 March 2021 3,867 3 View

Which cell line should we use to perform biological dosimetry experiments?

We are preparing some experiments based on irradiating cells under different conditions in order to evaluate the effects in terms of DNA damage, genetic expression, etc. As our project is...

01 March 2021 3,355 3 View

Why might my GFP tag be dissociating from my plasmid after transfection?

I have a set of stably transfected cell lines all transfected with plasmids containing GFP tags on the C terminus. During a western blot using anti-GFP antibody, one of my plasmids has dissociated...

01 March 2021 9,310 4 View

Is it possible for two human neuronal cell lines to have different gene sequence for the same protein?

I am looking at the ATP1A2 (Sodium/Potassium ATPase alpha subunit 2) in two human neuronal cell lines. Expression levels of this protein seems to be almost equal when detected by one antibody....

01 March 2021 3,607 3 View

Precipitate after adding laemmli buffer to protein solution containing Potassium Acetate?

Hi, I am running a size exclusion chromatography experiment with a buffer containing Potassium Acetate as a salt. I analyse these fractions through SDS-PAGE. After boiling my SEC fractions in...

01 March 2021 2,622 3 View

Is CD44 degraded in lysosome together with hyaluronan after CD44 mediated endocytosis of hyaluronic acid?

Also when RHAMM binds hyaluronic acid, they get internalized, will RHAMM also be degraded? Or both CD44 and RHAMM will be transferred back to the cell membrane? Asking for breast cancer cell line...

01 March 2021 8,169 2 View

What is the most suitable server for predicting protein structures in bacteria?

I have used the i-Tasser several times, however it has been unavailable for several days. I tried the swiss-model, but the output was not very pleasant due to the model used. Is there any other...

28 February 2021 4,521 3 View

Do you need the CMV enhancer before the CMV promotor for a proper function of CMV on the gene that follows?

I'm a student and I have to produce a cell line with a knockin for the NRF2 gene with GFP. I have to put a promotor in front of the GFP because the gene will be too far away from the promotor of...

28 February 2021 7,127 2 View