16 Questions 17 Answers 0 Followers
Questions related from Sherif Arafa
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...
07 July 2019 6,840 3 View
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...
05 May 2019 5,031 15 View
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?
05 May 2019 9,209 5 View
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...
08 August 2018 4,314 4 View
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...
06 June 2018 8,553 6 View
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...
05 May 2018 5,974 8 View
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 ?
05 May 2018 4,543 2 View
what is the carbon nmr chemical shift of methyl gp in acetyl gp
12 December 2017 9,481 3 View
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...
10 October 2017 8,839 3 View
I need any advice on how to be expert in structure elucidation using different NMR techniques..Is there any tutorials or books that can help me ?
09 September 2017 408 5 View
I am trying to grow fungi from soil using rose bengal agar medium .. can any one tell me how long does it take fungi to grow on this medium ...
09 September 2017 6,178 2 View
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 .....
09 September 2017 4,129 6 View
I have a 50 mg fraction and i will run column chromatography .. i want to know the appropriate column size
06 June 2017 5,395 2 View
I am working on a plant fraction and its weight is 24 mg.. I tried it on TLC normal phase using CHCl3 methanol system 10;1 and reversed phase using methanol; water 8;2 but there is tailing which...
05 May 2017 3,220 4 View
I have a fraction that shows 2 spots on reversed phase TLC with solvent system methanol : water 1:1 .. now i want to purify this fraction but the problem is that its weight is 5 mg and i know that...
05 May 2017 9,233 8 View
What is the best mobile phase for isolation of compounds from Aloe vera flower extract?
01 January 2016 349 2 View
