What type of ion exchange should I use?

Hi, I have an unknown protein with the following info: Protein seq: M S D S E V N Q E A K P E V K P E V K P E T H I N L K V S D G S S E I F F K I K K T T P L R R L M E A F A K R Q G K E M D S L R...

01 February 2016 4,447 4 View

Crystallography and asymmetric unit?

Hi, If my solved structure is a dimer in an asymmetric unit, are the two molecules correlated by crystallographic rotational symmetry? I think not, but have problem explaining it. I would be...

01 February 2016 2,802 2 View

What is Mathew's Coefficient?

01 February 2016 4,350 0 View

Why Austenite grains in steel show much more twinning than ferrite grains?

It is oftentimes said to be a distinctive metallographic trait that differentiates a fully austenitic and a fully felly ferritic steel without etching that might distinguish between two. Why...

02 March 2021 728 2 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

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

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

Are protein samples in SDS compatible with ELISA?

I have used an AllPrep DNA/RNA/Protein Mini Kit QIAGEN kit to extract RNA and protein from my samples. At the end of the protein purification, I resuspend my protein in 5% SDS. Will these samples...

28 February 2021 7,370 3 View

What could be the reason for not having further low chi square value (better agreement) in my refinement result?

I have tried every combination of parameter changes and after that i have a poor chi square value. I can't get it lower any further. I know there have been a lot of discussion about Rietveld...

26 February 2021 8,480 3 View

How to replicate the well conditions of a crystal hit with 20%(w/v) isopropanol?

I had a crystal hit in a well with 0.1M HEPEs pH 7.5, 10%(w/v) PEG 4000, and 20%(w/v) isopropanol. Why is isopropanol in w/v here if it's just solvent? How do I recreate this well condition?

25 February 2021 9,761 1 View

Problem with ligating 2.8 kb insert into 8.5 kb plasmid?

I am trying to clone 2 copies of the same mammalian gene into the pSF-CMV-Ub-Puro Ascl (contains HindIII, KpnI and NheI cut sites) plasmid. This is what the final product is supposed to look like...

24 February 2021 6,310 3 View

What urea buffer can i use for biotagged protein extraction from streptavidin beads?

Hi all, I have been doing research on biotagged LDB1 proteins in Mel cells. I purify the proteins using M280 streptavidin beads. The yield is very low so I've been trying to optimize it by...

24 February 2021 5,749 3 View