Rose bengal medium ?

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Enzyme activity not working?

I am trying to do an enzyme assay using Wild type enzyme the protocol involves tris buffer pH 8, MgCl2, S-adenosyl methionine, Substrate, and I inititate the reaction with my enzyme, but after...

06 July 2019 6,793 3 View

Protein size decreases after mutation?

I am trying to express mutants of my protein whose size is 30 Kda... however following purification by Ni affinity column ... the SDS PAGE shows the mutants appearnig at size 20 Kda.. is there a...

04 May 2019 4,982 15 View

BL21 pLyss transformation and chloramphenicol?

Do I need to add chloramphenicol to LB agar media when trying to transform my plasmid into BL21 pLyss or I can add only the antibiotic of my plasmid?

04 May 2019 9,156 5 View

Why protien not eluted after changing buffer ?

II am currently working on a protien to be crystallized. The protien is bound to FAD, that's why when I purify the protein with Ni affinity column its colour was yellow . but surprisingly, after...

07 August 2018 4,263 4 View

How to make protien soluble during expression ?

I am trying to express and purify a protein after doing all the steps and purify using Ni affinity column but after doing the SDS PAGE I found that the amount of protein in the elute is very...

05 June 2018 8,503 6 View

Use of precukture ?

I want to ask why we always do a starter preculture step during protein expression ? Why don't we just start the main culture directly ?

04 May 2018 4,468 2 View

Protien not purified using ion exhange?

I am trying to purify a protein..First I run Ni affinity column and the protein was eluted with KPB pH7.9, imidazole 500mM and glycerol ..then I diluted with No Salt buffer containg 50mM TrisHCL...

04 May 2018 5,921 8 View

Chemical shift of acetyl gp?

what is the carbon nmr chemical shift of methyl gp in acetyl gp

11 December 2017 9,435 3 View

Methoxy gp on aromatic ring ?

If i have an aromatic ring with methoxy gp on it and 3 aromatic protons in ortho, meta and para position ..Is there an explanation for why the ortho proton appears at lower chemical shift than...

09 October 2017 8,721 3 View

Isolation of soil microbes?

I have cultured soil on 2 medium .. humic acid medium and chitin agar medium for culture of fungi and actinomycetes.. the question is .. how can i know the colon grown is fungi or bacteria .....

08 September 2017 4,071 6 View

How to grow E.coli on the low salt LB agar plate with 50 or 100ug/ml of Blasticidin?

Hello, I would like to ask how to grow E.coli which resists 50 or 100ug/ml of Blasticidin. I have tried many methods by using low salt Luria-Bertain(LB) agar plate. However, no colonies grow. Let...

01 March 2021 2,027 2 View

Isolates of Hymenoscyphus fraxineus?

Dear Dr. Cai, my name is Simone Prospero and I work in the team of Phytopathology at the Swiss Federal Institute for Forest Snow and Landscape Research (WSL;...

01 March 2021 1,133 1 View

How to remove the residual PDMS on the silicon mold?

Incompletely cross-linked pdms are difficult to remove.

01 March 2021 798 3 View

Can bacterial suspension be pipetted directly onto petri dish and agar poured onto it?

Hi, recently I encountered a protocol for plating which was not the usual method I have been practicing (pour LB agar onto plate, allow it to solidify, pipette bacterial suspension onto plate,...

28 February 2021 7,292 3 View

The reason that the culture of white fungi Contamination with green mold(Trichoderma), the culture autoclave at121 for 15 min. What is it?

Is the period to autoclave not enough? The inoculation in a hood and flame and UV and alcohol.

27 February 2021 9,356 3 View

What is the most suitable medium of ascomycetes fungi ??

26 February 2021 4,413 1 View

Does RNAiMAX transfection reagent work in serum free medium?

I diluted siRNA and RNAiMAX in opti-MEM and added to the cells which they were in the growth medium. Is it a right way? or should I culture cells in the opti-MEM medium for a while and not in...

26 February 2021 10,041 3 View

Has anyone used the Illumina ITS1 primer sets?

Hi everyone, Illumina provides a list of primers to amplify with high taxonomic coverage the ITS1 region for further fungal sequencing, but I cannot find the exact amount necessary of each...

25 February 2021 6,969 3 View

Difficulty in cloning of 1kb gene into vector?

I am facing difficulties in cloning a 1kb gene into a vector (pJIT163). I have my gene on interest (GOI) in pUC57 and want to clone in pJIT163 using SalI and BamHI restriction sites. I am getting...

25 February 2021 3,221 7 View

Is this the write procedure for acid digestion of soil for heavy metal analysis using AAS?

How to do acid digestion of soil sample with 3:1 aquaregia in an open vessel?

23 February 2021 3,053 7 View