David Vizarraga

22 Questions 27 Answers 0 Followers

Questions related from David Vizarraga

How could I stop the autoproteolysis process?

Hi all My name is David Vizarraga. I am trying to purify a protein. But When i purify it, after a few days It begins to autoproteolyze. It forms the same fragments in all bach of protein...

08 August 2017 1,253 6 View

What do you think it is?

Good afternoon. I attach an imagen and my question is what do you think it is? I think It is a lot of microcrystalls. In the top of the drop there are microcrystalls alone (unit) and in the...

04 April 2017 6,994 1 View

How can I remove DNAk from my protein solution?

Hi all. I have a pure protein but DNAk is together with my protein. How can I remove DNAk? and If I remove it could the protein suffer any effects? Thank you

01 January 2017 2,593 3 View

What can i do so my protein will be finished the folding?

Hi all. I have a pure protein but in SDS-PAGE gel there is DNAk in the solution too ( It is together with my protein). In Superose6 column I have 3 proximate peaks which I cant separated. I think...

01 January 2017 3,204 8 View

A rare purification How could I obtain the monomer or one of the oligomers?

Hi all. I am a PhD student who work in protein purification and crystallization. A few months ago I started with a protein which molecular weight is very big around 100kDa (monomer). When I...

01 January 2017 6,389 2 View

What Could I do for improve on the protein expression for end the fold of my protein ?

Hi all. I wrote some times here about a unfold protein topic. The case is I have a pure protein but It is together with DNAk and In the exclusión molecular column I have several peaks that I...

01 January 2017 8,460 5 View

Protocol for E.coli expression/induction with a Heat shock step?

Hi all. I want to high the amount of the Heat shock chaperones concentration. I read one option is to do a Heat shock step before the protein induction. Anyone know How could I do? Thank you.

01 January 2017 7,049 2 View

Could My protein be affected with the sonication method?

Hi all. I want purify a protein. The special of my protein is that the oligomers or the aggregates broken when I centrifugated. So I want know If My protein could be affected with the...

12 December 2016 4,615 12 View

Which is the perfect buffer for my protein?

Hi all I want to purify a protein (Pi:4,0) and I am use a Typical buffer (50mM Tris pH: 7,4, 200mM NaCl and 10mM glucose ( decreased the aggregates and It is better for the crystallization than...

11 November 2016 9,660 1 View

My protein forms aggregates but I couldnt use additives like glucose or glycerol because It forms oligomers What could I do in my purification step?

Hi all. My protein forms aggregates but I couldnt use any additives like glucose or glycerol because It forms oligomers. Thank you

11 November 2016 2,779 9 View

Why after centrifugation at 13,2RPM during 2 hours does my protein broken in the linear monormer?

Hello. My name is David Vizarraga and I am a PhD student. I am trying to purify a protein but I always have a oligomer mix in the solution and I can't crystallize it (because I need a pure...

11 November 2016 5,188 3 View

What is happening in the E.Coli Articexpress transformation?

Hi all, I want transform in E.Coli ArticExpress for stabilize my protein in one of the oligomers that I have. Now I am doing the transformation in BL21(DE3), and I obtained more than 200 colonies...

10 October 2016 1,755 1 View

Do you need a homogeneous sample for Electron microscopy?

Hi I would want try EM (negative stain method) with my sample but in size exclusion column I identify 3 different oligomers. Can I do EM? or I need a homogeneous sample. Thank you

10 October 2016 6,496 3 View

How could I separate DNAk of my protein?

I purify my protein but in SDS-PAGE gel I have two proteins ( my protein and DNAk). I cant separate with Size exclusion column so I supposed both proteins are attached. So I want separated my...

09 September 2016 8,382 4 View

Hi all, I want to solve a protein structure but it is very difficult because the monomer forms a disc stack line. How I stabilize the monomeric form?

Thank you. Protein buffer: 200mM NaCl, 50mm Tris pH:7,6 and 10% glycerol

09 September 2016 6,904 5 View

Could you let me any considerations about the crystallization conditions of my protein?

Hi all, I have a pure protein and i want crystallize it. My proteina is a high molecular weight (1.300kDa) and i want know the best protein concentration and conditions for crystallization this...

09 September 2016 6,065 4 View

Could the Tris concentration change the chromatography profile?

Hi all. I try to purify a High molecular weight protein. I explain my case: I did two purification with the same Culture and induction conditions. But when i purified the protein accidentally I...

09 September 2016 1,480 5 View

Stability protein in the purification. Could you help me?

Hi. I did a lot of trials of protein purification but i couldnt stabilized the protein. I explain the case: When i did the protein purification in the buffer: Tris 50mM NaCl 150mM pH 7,6 the...

08 August 2016 1,898 11 View

What happend in my protein purification?

Hello everyone, I try to purify a High molecular weight protein. But i have a big problem because it forms aggregates. I try to add glycerol (5-10%) or increasing the NaCl concentration of 0,15M...

08 August 2016 5,484 11 View

How much amount of L-arginine do I need along the protein purification?

Dear all I tried a protein purification with L-Arginine 0,4M but my protein doesnt bind in HisTrap, then i reduced it to 0,2M and in the rest of the buffers I used a 0,4M concentration. With this...

08 August 2016 2,260 3 View

How can I improve crystal diffraction?

Hi to all. I am working with a protein which crystallizate in several forms with differents cells. The crystalls appear in 1-2 days ( overnight appear too) I tried to optimizate the crystals with...

01 January 1970 8,180 1 View

Can NaCl increase the protease/degradation activity of a protein?

Hello everyone. I explain my case: I had a protein with this purification protocol: Histrap-MonoQ-Superdex. The protein buffer is Tris 20mM 150mM NaCl pH:7.4. In this case, the protein degraded or...

01 January 1970 9,566 5 View